- Email: [email protected]
Short-term water-based aerobic training promotes improvements in aerobic conditioning parameters of mature women
Accepted Manuscript Short-term water-based aerobic training promotes improvements in aerobic conditioning parameters of mature women Rochelle Rocha Costa, Thais Reichert, Leandro Coconcelli, Nicole Monticelli Simmer, Natália Carvalho Bagatini, Adriana Cristine Koch Buttelli, Cláudia Gomes Bracht, Ricardo Stein, Luiz Fernando Martins Kruel PII:
S1744-3881(17)30127-5
DOI:
10.1016/j.ctcp.2017.06.001
Reference:
CTCP 739
To appear in:
Complementary Therapies in Clinical Practice
Received Date: 27 March 2017 Revised Date:
3 June 2017
Accepted Date: 4 June 2017
Please cite this article as: Costa RR, Reichert T, Coconcelli L, Simmer NM, Bagatini NatáCarvalho, Buttelli ACK, Bracht CláGomes, Stein R, Kruel LFM, Short-term water-based aerobic training promotes improvements in aerobic conditioning parameters of mature women, Complementary Therapies in Clinical Practice (2017), doi: 10.1016/j.ctcp.2017.06.001. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Title Page
ACCEPTED MANUSCRIPT Title: Water-based aerobic training of only five weeks promotes improvements in aerobic conditioning parameters of elderly women
Running Head: Water-based training and aerobic conditioning
Authors: 1
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1) Rochelle Rocha Costa (Costa, RR) - phone: 55 51 999090212 - email: [email protected] 1
2) Thais Reichert (Reichert, T) - phone: 55 51 982433007 - email: [email protected] 1
3) Leandro Coconcelli (Coconcelli, L) - phone: 55 51 982870056 - email: [email protected] 1
4) Nicole Monticelli Simmer (Simmer, NM) - phone: 55 51 993213113 - email: [email protected] 1
5) Natália Carvalho Bagatini (Bagatini, NC) - phone: 55 51 992154443 - email: [email protected] 1
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6) Adriana Cristine Koch Buttelli (Buttelli, ACK) - phone: 55 51 999071199 - email: [email protected] 1
7) Cláudia Gomes Bracht (Bracht, CG) - phone: 55 51 996222433 - email: [email protected] 2
8) Ricardo Stein (Stein, R) - phone: 55 51 997073321 - email: [email protected] 1
Affiliations:
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9) Luiz Fernando Martins Kruel (Kruel, LFM) - phone: 51 55 998063309 - email: [email protected]
Federal University of Rio Grande do Sul - School of Physical Education - 750 Felizardo
Street - Porto Alegre City - Rio Grande do Sul State – Brazil; 2
Hospital de Clínicas de Porto Alegre - 2350 Ramiro Barcelos Street - Porto Alegre City - Rio
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Grande do Sul State – Brazil
Affiliation where the research was conducted: Federal University of Rio Grande do Sul - School of Physical Education - 750 Felizardo Street - Porto Alegre City - Rio Grande do Sul State –
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Brazil.
Corresponding Author: Rochelle Rocha Costa.
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Exercise Research Laboratory - 750 Felizardo Street – Postal Code 90690-200 Porto Alegre, RS, Brazil Telephone number: 0055(51)3308 5820 - FAX 0055(51)3308 5817 e-mail: [email protected] Acknowledgements
We acknowledge financial support from CAPES, CNPq and FIPE-HCPA.
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Title: Short-term water-based aerobic training promotes improvements in aerobic
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conditioning parameters of mature women
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Running head: Water-based training and aerobic conditioning
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5 ABSTRACT
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Aging is accompanied by a decrease in aerobic capacity. Therefore, physical training has
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been recommended to soften the effects of advancement age. The aim of this study was to
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assess the effects of a short-term water-based aerobic training on resting heart rate (HRrest),
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heart rate corresponding to anaerobic threshold (HRAT), peak heart rate (HRpeak), percentage
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value of HRAT in relation to HRpeak and test duration (TD) of mature women. Twenty-two
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women (65.91 ± 4.83 years) were submitted to a five-week water-based interval aerobic
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training. Aerobic capacity parameters were evaluated through an aquatic incremental test.
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After training, there was an increase in TD (16%) and HRAT percentage in relation to HRpeak
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(4.68%), and a reduction of HRrest (9%). It is concluded that a water-based aerobic interval
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training prescribed through HRAT of only five weeks is able to promote improvements in
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aerobic capacity of mature women.
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Keywords: Aging, aerobic training, aquatic environment, heart rate, anaerobic threshold.
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INTRODUCTION Mature population has been showing an exponential growing worldwide (United
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Nations, 2009). According to United Nations (UN) data, the mature population currently
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represent 12.3% of the world population and, projections indicate that in the year of 2050
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they will represent 22%, including overcoming the number of young people. These data
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demonstrate the importance of investigations performed in the aging field.
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Aging is accompanied by a series of alterations in the organism, among them, we can
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highlight the decrease of aerobic capacity: it is estimated that a reduction of 10% by decade
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of life occurs from 20 years old (Fleg et al., 2005). This process is extremely relevant once
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aerobic capacity is related to functional capacity and is an independent predictor of mortality
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(Myers et al., 2015). Thus, stimulating the maintenance or even increasing the levels of
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aerobic capacity of mature individuals is fundamental in order to increase the capacity to
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accomplish daily life activities and to help to decrease mortality in this population.
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Aiming to promote improvements in aerobic capacity, aerobic training has been
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widely recommended. Within this context, water-based aerobic training gets highlighted for
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providing physical exercise practice with lower joint impact (Alberton et al., 2013; Alberton
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et al., 2014) and lower levels of arterial blood pressure and heart rate due to the lower
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sympathetic and adrenergic activation and to the suppression of rennin-angiotensin system
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(Pendergast et al., 2015). In this way, water-based aerobic training is performed with greater
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cardiovascular and osteoarticular safety, decreasing injury risk (Chu & Rodes, 2001) and
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making the activity interesting for mature people. Although aquatic environment shows these
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beneficial characteristics, only two studies investigated the effects of water-based aerobic
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training on aerobic capacity in the mature population (Takeshima et al. 2002, Bocalini et al.
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2008). In both studies, the authors observed gains in peak oxygen consumption of mature
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women submitted to a combined training (strength and aerobic) of 12 weeks of duration (12
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and 42%, respectively). Moreover, Takeshima et al. (2002) verified an increase of 20% in
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oxygen consumption corresponding to anaerobic threshold (VO2AT). Oxygen consumption is
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the best aerobic capacity representative (gold standard) and aerobic training prescription by
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means of anaerobic threshold can be determined through the ventilatory method during a
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cardiopulmonary exercise test (Delevatti et al., 2015). However, the availability of a gas
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analyzer is needed, which limits its applicability in the real world. Faced with that, the
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method based on the heart rate deflection point (HRDP) for training prescription has been
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gaining prominence for being easy applicable, low cost and associated with the anaerobic
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threshold determined by the ventilatory method (Alberton et al. 2013a; Delevatti et al. 2015;
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Kanitz et al. 2015; Pinto et al., 2016). HRDP method is based on the relationship between
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heart rate (HR) and intensity during an incremental exercise testing: this relationship is
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curvilinear (Kanitz et al., 2015). The point in which there is a break of the linear relationship
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(HRDP) is associated with the anaerobic threshold. In this way, this kind of test allows to
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asses several parameters related to aerobic capacity (resting HR, HR corresponding to
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anaerobic threshold, peak HR, among others) with a greater practical applicability in clubs
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and gyms, for being low cost and time-efficient, once that more than one individual can be
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evaluated at the same time.
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Thereby, the purpose of the present study was to assess the effects of a short-term
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water-based aerobic training on resting HR (HRrest), HR corresponding to anaerobic threshold
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(HRAT), peak HR (HRpeak), HRAT percentage in relation to HRpeak and test duration in mature
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women.
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METHODS
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Experimental design
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This is a study of exercise training intervention.
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Participants Twenty-three mature women who were initially sedentary (non-practitioners of
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systematized exercise in the previous three months), aged between 60 and 75, non-smoking
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and free from cardiovascular diseases (with the exception of controlled hypertension)
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participated in the study. Previously to the study entry, all participants performed a complete
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medical evaluation (clinical history, physical exam, 12-lead resting electrocardiogram and an
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exercise incremental test), signing an informed consent form in duplicate. The study was
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approved by the Ethics Committee of the Federal University of Rio Grande do Sul (UFRGS)
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and by the Clínicas Hospital of Porto Alegre (140547).
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Procedures
Participants attended the Swimming Center of the Physical Education, Physiotherapy
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and Dance School (ESEFID) of UFRGS in five occasions previously to the beginning of the
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water-based aerobic training. On the first visit, the volunteers received information about the
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study procedures, filled an anamnesis and signed the informed consent form. On the second
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visit, body mass (BM) and height measurements were made, and a first familiarization
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session to the aquatic environment was conducted, as also to the exercises that would be
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subsequently performed in the aerobic training protocol. On the third visit, the participants
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accomplished a second familiarization session to the aquatic environment, as also to the
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incremental test procedures and to the heart rate monitor equipment. On this occasion the
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incremental tests in aquatic and land environments were scheduled. The incremental test in
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aquatic environment was performed on the fourth visit. At the end of this test, the land
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incremental tests (on treadmill) were scheduled, which were performed on the fifth visit. It is
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important to highlight that between all visits a minimum interval of 72 hours was given. All
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participants were oriented to not drastically alter their feeding habits and to not perform
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additional physical activities (as exercise), to the ones prescribed in the proposed aerobic
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training, during the five weeks of intervention. Besides that, they were also oriented to inform
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the researchers in case of alteration in their daily use medication through the study period.
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Incremental test in aquatic environment
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Incremental tests in aquatic environment were conducted before the beginning of the
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training sessions and after the end of five weeks, in the pool of the Swimming Center of
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ESEFID/UFRGS. Tests were accomplished in controlled conditions, with water temperature
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between 29 and 31 °C, adopting immersion depth between the height of xiphoid process and
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shoulders of each participant.
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Previously to the beginning of each test, using a HR monitor, participants remained
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immersed, in orthostatic position, in silence and in absolute rest during five minutes and the
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lower HR value observed during this period was registered as HRrest. For the protocol of the incremental test, which was accompanied by a trained
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physician, the stationary run exercise was adopted, starting with warming-up of three minutes
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in the cadence of 85 beats per minute (bpm), with subsequently increments of 15 bpm in the
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cadence at each two minutes, until the participants reached self-reported exhaustion. Besides
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that, range of motion was controlled at 90º of hip and knee flexion, and the test was
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interrupted when the volunteers could not maintain the exercise in the rhythm dictated by the
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cadences. HR was collected at each 10 seconds for the determination of HRDP, which was
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used for the HRAT identification, once that this point is strongly correlated with the anaerobic
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threshold determined by the ventilatory method (Alberton et al., 2013a). To do so, a HR
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monitor (POLAR, FT1, Finland) and a standardized form for recording the data were used.
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For the determination of the execution rhythm of the exercise, a metronome (KORG, MA-30,
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Japan) was utilized. Collected data, in the sampling rate of 10s, were then plotted in a
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dispersion graph and thus HRDP was determined, according to the methodology
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demonstrated in the study of Alberton et al. (2013a). The determination of the point referring
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to HRAT was made in an independent and blinded manner by three experienced researchers.
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Discordances were decided by consensus when possible, or alternatively the median of the
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three values was adopted. The cadence in which each participant was exercising at the
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moment corresponding to anaerobic threshold was determined as CadenceAT.
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At the end of the test, total time spent (test duration - TD) was registered in minutes,
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until the voluntary exhaustion of the participant or the inability in maintaining the correct
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range of motion of the movement within the determined cadence. The highest HR value near
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the end of the test was adopted as HRpeak in this study. With this values, percentage value of
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HRAT corresponded to HRpeak was determined (%HRpeakAT). The last cadence performed in
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each test was registered as Cadencepeak, representing the greater cadence reached by each
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participant.
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Incremental test in land environment
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Incremental test in land was performed in order to obtain HRpeak in land environment
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(HRpeak_land) and was used for sample characterization. For this, a treadmill (INBRAMED,
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ATL, Brazil), with a 0.01 km.h-1 resolution for speed and 1% for inclination, and the same
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HR monitor equipment adopted in the aquatic environment were used. All women remained
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seated on a chair on the treadmill during five minutes, allowing the stabilization of the HRrest
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and enabling the instructions for the test. The Bruce protocol (Bruce et al., 1973) was
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adopted, in which increments of speed and inclination were conducted at each three minutes.
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HR was collected and registered at each 30s. The test was interrupted when the volunteer
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indicated her exhaustion, through a manual sign previously arranged and at this moment HR
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was finally registered. The greater HR value reached near the end of the test was adopted as
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HRpeak_land.
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Both tests, in aquatic and land environment, were performed during the morning shift,
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and participants were instructed to maintain the use of their daily medication at the usual
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time. Furthermore, they were instructed to not feed themselves in the three hours previously
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to the tests, and to not attend in night fasting, besides not consuming stimulants and not
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practicing intense physical activities in the 24 hours before the tests (Cooke, 1996).
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Water-Based Aerobic Training
Aerobic training sessions were performed at the pool of the Swimming Center of
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ESEFID/UFRGS and instructed by a Physical Education professional with previous
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experience in water-based aerobic bouts, monitored by an assistant, aiming to ensure that the
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target intensity was reached. Total training period was five weeks, during which the
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participants performed two weekly sessions of 45 minutes each. Whenever necessary,
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recovery sessions were offered within the same week for those participants who might have
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missed some session. Besides that, no alteration in daily medication was notified during the
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study period. All sessions was composed by an initial warm-up, with duration of seven
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minutes, main part (composed by aerobic training), with duration of 30 minutes, and a cool
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down, with duration of eight minutes.
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In the main part of the training sessions, four exercises were adopted, bilaterally
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performed in a combined manner (each lower limbs exercise was associated with an upper
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limbs exercise). The exercises are demonstrated on Figure 1.
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****Figure 1 near here****
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Training intensity control was performed with the use of HR monitors, being
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controlled by a zone corresponding to HRAT. Training was conducted adopting the interval
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method, alternating four minutes in the intensity corresponding to HR range of 90 and 95%
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HRAT and one minute between 80 and 85% HRAT (Table 1).
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*****Table 1 near here****
Statistical Analysis
Scalar variables data are presented as means and standard deviations. On the other
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hand, ordinal data (CadenceAT and Cadencepeak) are presented as median and interquartile
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interval. Normality of dependent variables data was tested adopting Shapiro-Wilk test. After
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the normality confirmed, the comparison of the data in pre- and post-training moments
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(temporal analysis) was performed by T-Test for paired samples. The comparison of medians
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of cadences at pre- and post-training was performed by Wilcoxon Test. Both analyses
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adopted a significance level of 5% (α = 0.05). Statistical procedures were performed in the
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Software SPSS version 22.0.
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The whole sample (n = 23) finished the five weeks of water-based aerobic training,
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RESULTS
showing 100% adherence to the proposed protocol (10 sessions). Sample characterization data, including age, body mass, height and body mass index
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of the mature women who participated in the study are presented on Table 2.
****Table 2 near here****
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In regard to the temporal behavior of the dependent variables, it was observed that
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HRrest showed a significant reduction of 8 bpm after five weeks of aerobic training in aquatic
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environment. In contrast, HRAT and HRpeak did not suffer any significant alterations over this
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period. The TD showed significant increase of 1 min and 49 seconds in the comparison
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between the tests performed in the beginning of the training and after the fifth week,
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indicating that the participants took more time to reach exhaustion. In addition, %HRpeakAT
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suffered a significant increment of 4.68% after the five weeks of training. The CadenceAT
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was improved in 1 cadence (15 bpm) from pre- to post-training, such as the Cadencepeak (15
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bpm after 5 weeks of training). Such data and the statistical significance of the time
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comparison are presented on Tables 3 and 4.
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****Table 3 near here**** ****Table 4 near here****
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DISCUSSION
The main finding of the present study was that only five weeks of water-based aerobic
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training were enough for promoting an improvement of aerobic capacity of mature women,
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evidenced by the decrease of HRrest, increase of test duration and %HRpeakAT.
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Aging process is associated to an increase of sympathetic nervous system activity
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(Fiuza-Luces et al., 2013), reflecting on a tendency of increased HRrest. This alteration in
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cardiovascular system demands concern, once increased HRrest is considered a risk factor for
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mortality (increased risk of 16% at each 10 bpm) (Jensen et al., 2013). In contrast, this
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deleterious effect of aging can be minimized by aerobic training: a decrease of about 1 bpm
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at each training week is expected in sedentary individuals, mainly in the first 10 weeks
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(Wilmore et al., 2010). In fact, the interval aerobic training proposed in the present study
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promoted a reduction of HRrest, which was even higher than expected (1.6 bpm per week).
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This is a finding of clinical relevance, since it represents a decrease of approximately 13% in
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all-cause mortality risk (Jensen et al., 2013).
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The results of the present study corroborate the findings of Bocalini et al. (2008), who
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observed a significant reduction of HRrest from 92 to 83 bpm after 12 weeks of water-based
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aerobic training in mature women. On the other hand, Takeshima et al. (2002) did not
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verified significant alterations in HRrest of mature women after 12 weeks of water-based
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aerobic training. Possibly, the results found by Takeshima et al. (2002) may have been
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attributed to the lower HRrest of the participants in the pre-training status (77bpm), which
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reduced the possibility of improvement of these individuals, unlike the data of our study
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participants and the study of Bocalini et al. (2008).
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On the other hand, we did not observe a significant difference in HRAT after
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intervention. Only two previous studies investigated the effects of water-based aerobic
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training on parameters corresponding to AT (Pinto et al., 2015; Takeshima et al., 2002).
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Although these studies did not enroll exclusively mature individuals, Pinto et al. (2015)
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observed increments in VO2AT of postmenopausal women (7 to 11%) and Takeshima et al.
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(2002) of mature women after 12 weeks of training (20%). It is speculated that the absence of
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adaptation occurred in our study may be related to the shorter intervention period (five weeks
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versus12 weeks) and to the lower training intensities (90-95% HRATversus100% HRAT) used.
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Maintenance was also observed in HRpeak after training. Corroborating our result,
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Takeshima et al. (2002) did not find adaptations in HRpeak after 12 weeks of water-based
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aerobic training. Indeed, little or no adaptation is expected in this outcome after an aerobic
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program (Wilmore et al., 2010). It is highlighted that the HRpeak reached in the incremental
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test in aquatic environment was much lower than the one obtained in land (133 versus 145
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bpm). This behavior was already expected and can be explained by the physical properties of
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aquatic environment. During immersion, hydrostatic pressure and thermoconductivity
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increase pre load (venous return), causing an increment of blood volume in the central region
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of the organism (Arborelius et al., 1972, Pendergast et al., 2015). This hypervolemia causes
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an increase of the end-diastolic volume, which will promote an increase of stroke volume and
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cardiac output, with consequent HR reduction (Arborelius et al., 1972; Pendergast et al.,
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2015). Although alterations in HRAT an in HRpeak were not evidenced, the cadence in which
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these moments occurred was significantly increased after the 5 weeks of training. The
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maintenance of a same value of HR in greater cadences can be viewed as a favorable
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adaptation, indicating cardiorespiratory and metabolic economy in response to the increase of
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the external loads, which may be due to an improvement in the venous return and increase of
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the stroke volume. Another reasonable explanation is the possible increase in the strength
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levels after the 5 weeks of aquatic training, given that the exercises, even if prescribed in
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aerobic intensities, are performed against the resistance promoted by water, which can
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generate neuromuscular adaptations that favor to support higher intensities as those observed
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in the greater cadences.
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It is important to mention that a significant increase of test duration and %HRpeakAT
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after water-based aerobic training was observed. The augmentation of one minute in test
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duration represents that the mature women were able to support the exercise for a longer time
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and in greater intensities. Regarding to %HRpeakAT, it reflects that our sample of mature
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women were able to reach the anaerobic threshold in a HR percentage closer to HRpeak,
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showing an improvement in aerobic capacity after the proposed intervention. It is emphasized
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that the mature women presented a higher %HRpeakAT already at pre-training in comparison
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to studies performed on land environment, which assessed the percentage of a
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cardiorespiratory parameter in relation to the maximum (Chtara et al., 2005; Cadore et al.,
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2012a; Ferrari et al., 2013; Kanitz et al., 2015). This result may be explained by the
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augmentation of blood volume in the central region of the organism. Central hypervolemia
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causes an increase in alveolar pressure, which might result in an increased oxygen release in
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the bloodstream, promoting a greater supply of oxygen to the tissues. In this way, in aquatic
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environment there is a greater energy supply through anaerobic route in comparison to land
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environment. A possible limitation of the present study is the absence of a control group. However,
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it is highlighted that this is an area where evidences are lacking, since that only two studies in
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the literature assessed the effects of water-based aerobic training on aerobic capacity of
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mature women. In this sense, our findings are innovative, as they demonstrate that only five
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weeks of water-based aerobic training prescribed through HRAT promotes improvements in
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aerobic capacity of mature women, improving their capacity to accomplish their daily life
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activities and decreasing their mortality risk. Finally, we presented a test of low cost and easy
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applicability that, besides being used for training prescription, it also can be used in the
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evaluation of aerobic capacity parameters.
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CONCLUSION
A water-based aerobic interval training prescribed through HRAT of only five weeks is
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able to promote a significant reduction of HRrest and an increment of test duration and
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%HRpeakAT, showing an improvement in aerobic capacity of mature women.
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312 313 314 315
Alberton, C.L., A.C. Kanitz, S.S. Pinto, A.H. Antunes, P. Finatto, E.L. Cadore and L.F.M. Kruel. 2013a. Determining the anaerobic threshold in water aerobic exercise: a comparison between the heart rate deflection point and the ventilatory method. Journal of Sports Medicine and Physical Fitness 53: 358-67.
316 317 318 319
Alberton, C.L., M.P. Tartaruga, S.S. Pinto, E.L. Cadore, A.H. Antunes, P. Finatto and L.F Kruel. 2013. Vertical ground reaction force during water exercises performed at different intensities. International Journal of Sports Medicine 34(10): 881-87. doi: 10.1055/s-00321331757
320 321 322 323
Alberton, C.L., S.S. Pinto, E.L. Cadore, M.P. Tartaruga, A.C Kanitz, A.H. Antunes, P. Finatto and L.F.M. Kruel. 2014. Oxygen uptake, muscle activity and ground reaction force during water aerobic exercises. International Journal of Sports Medicine 35: 1161-69. doi:10.1055/s-0034-1383597
324 325
Arborelius Jr. M., U. I. Ballidin, B. Lilja and C. E. Lundgren.1972.Hemodynamic changes in man during immersion with the head above water. Aerospace medicine 43(6), 592-98.
326 327 328
Boccalini, D.S., AJ.Serra, N. Murad and R.F. Levy. 2008. Water-versus land-based exercise effects on physical fitness in older women. Geriatrics & Gerontology 8: 265-71. doi: 10.1111/j.1447-0594.2008.00485.x
329 330 331
Bruce, R.A., F. Kusumi and D. Hosmer. 1973. Maximal oxygen intake and nomographic assessment of functional aerobic impairment in cardiovascular disease. American Heart Journal 85:546–62.
332 333 334 335
Cadore, E. L., M. Izquierdo, C. L. Alberton, R. S. Pinto, M. Conceição, G. Cunha, et al. 2012. Strength prior to endurance intra-session exercise sequence optimizes neuromuscular and cardiovascular gains in elderly men. Experimental Gerontology 47(2), 164-69.doi:10.1016/j.exger.2011.11.013
336 337 338 339
Chtara, M., K. Chamari, M. Chaouachi, A. Chaouachi, D. Koubaa, Y. Feki, G.P. Millet and M. Amri. 2005. Effects of intra-session concurrent endurance and strength training sequence on aerobic performance and capacity. British Journal of Sports Medicine 39(8), 555-60. doi: 10.1136/bjsm.2004.015248
340 341 342
Chu, K.S., and E.C. Rhodes. 2001. Physiological and cardiovascular changes associated with deep water running in the young. Possible implications for the elderly. Sports Medicine 31(1): 33-46.
343 344 345
Cooke, C.B., R. Eston and T. Reilly. 1996. Metabolic rate and energy balance. Kinanthropometry and exercise physiology laboratory manual. London: E & FN Spon p.175-95.
346 347 348 349
Delevatti, R.S., A.C. Kanitz, C.L. Alberton, P.D. Pantoja, E.C. Marson, C.D.F. Pinho, S.C. Lisboa, L.P. Bregagnol and L.F.M. Kruel. 2015. Heart Rate Deflection Point as an Alternative Method to Identify the Anaerobic Threshold in Patients with Type 2 Diabetes. Apunts. Medicina de l'Esport 50(188):123-28.doi:10.1016/j.apunts.2015.05.001
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Ferrari, R., L. F. M. Kruel, E. L. Cadore, C. L. Alberton, M. Izquierdo, M. Conceição, et al.
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2013. Efficiency of twice weekly concurrent training in trained elderly men. Experimental Gerontology 48(11), 1236-42.doi: 10.1016/j.exger.2013.07.016
353 354
Fiuza-Luces, C., N. Garatachea, N. A. Berger, & A. Lucia. 2013. Exercise is the real polypill. Physiology 28(5), 330-58.doi:10.1152/physiol.00019.2013
355 356 357
Fleg, JL., C.H. Bos. A.G. Morrel, L.J. Brant, LA. Talbot, J.G. Wright and E.G. Lakatta. 2005. Accelerated Longitudinal Decline of Aerobic Capacity in Healthy Older Adults. Circulation 112(5): 674-82. doi: 10.1161/CIRCULATIONAHA.105.545459
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Jensen, M.T., P. Suadicani, H.O. Hein and F. Gyntelberg. 2013. Elevated resting heart rate, physical fitness and all-cause mortality: a 16-year follow-up in the Copenhagen Male Study. Heart 99: 882–87.doi:10.1136/heartjnl-2012-303375
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Kanitz, A. C., R. S. Delevatti, T. Reichert, G. V. Liedtke, R. Ferrari, B. P. Almada, et al. 2015. Effects of two deep water training programs on cardiorespiratory and muscular strength responses in older adults. Experimental Gerontology 64, 5561.doi:10.1016/j.exger.2015.02.013
365 366 367
Mekjavic, I. B. and J. Bligh. 1989. The increased oxygen uptake upon immersion. European journal of applied physiology and occupational physiology 58(5), 556-62.doi: 10.1007/BF02330712
368 369 370 371
Myers, J., P. McAuley, C. J. Lavie J. P. Despres, R. Arena & P. Kokkinos. 2015. Physical activity and cardiorespiratory fitness as major markers of cardiovascular risk: their independent and interwoven importance to health status. Progress in cardiovascular diseases, 57(4), 306-14. doi:10.1016/j.pcad.2014.09.011
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Pendergast, D. R., R. E. Moon, J. J. Krasney, H. E. Held, & P. Zamparo. 2015. Human physiology in an aquatic environment.. Comprehensive Physiology 5: 1705-50. doi: 10.1002/cphy.c140018
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Pinto, S. S., C. L. Alberton, N. C Bagatini, P. Zaffari, E. L. Cadore, R. Radaelli, et al. 2015. Neuromuscular adaptations to water-based concurrent training in postmenopausal women: effects of intra session exercise sequence. Age 37(1), 1-11.doi: 10.1007/s11357-015-97517
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Pinto, S. S., R. M. Brasil, C. L. Alberton, H. K. Ferreira, N. C. Bagatini and J. Calatayud, & J. C. Colado. 2016. Noninvasive Determination of Anaerobic Threshold Based on the Heart Rate Deflection Point in Water Cycling. The Journal of Strength & Conditioning Research 30(2): 518-24.
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Takeshima, N., M.E. Rogers, E. Watanabe, W.F. Brechue, A. Okada, T. Yamada, et al. 2002. Water-Based Exercise Improves Health-Related Aspects of Fitness in Older Women. Medicine and Science in Sports and Exercise 34(3): 544-51.
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United Nations. 2009. World Population Ageing 2009. http://www.un.org/esa/population/publications/WPA2009/WPA2009_WorkingPaper.pdf (accessed December 20, 2016).
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Wilmore, J.H., D.L. Costill and W.L. Kenney. Physiology of Sports and Exercise. 4a Edition. United States: Human Kinetics, 2010.
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4 min 6
1 min
Exercises 1) Hip flexion/extension + elbow flexion/extension 2) Hip flexion/extension + shoulder horizontal flexion/extension 3) Hip flexion/extension + elbow flexion/extension 4) Hip flexion/extension + shoulder horizontal flexion/extension 1) Knee flexion/extension + elbow flexion/extension
Duration of each exercise
Intensity
1 min
90 to 95% HRAT
1 min
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HRAT: Heart rate corresponding to anaerobic threshold.
Total Duration
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Sets
80 to 85% HRAT
30 min
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Minimum Maximum
65.91 ± 4.83
60
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BM (kg)
74.16 ± 13.70
55.30
110.70
Height (m)
1.57 ± 0.06
1.45
1.68
HRpeak_land (bpm)
145 ± 18.09
112
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BMI (kg.m-2)
30.03 ± 4.97
22.59
43.15
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Age (years)
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BM: body mass; HRpeak_land: peak heart rate in land
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environment; BMI: body mass index.
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Post-training p (Mean ± SD)
HRrest (bpm)
89 ± 8.60
81 ± 9.54
<0.001
HRAT (bpm)
117 ± 13.51
121 ± 18.98
0.230
HRpeak (bpm)
133 ± 16.29
130 ± 21.34
0.322
TD (min)
9.51 ± 2.92
11.00 ± 3.03
0.044
%HRpeakAT (%)
87.79 ± 5.90
92.47 ± 3.78
0.005
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(Mean ± SD)
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HRrest: resting heart rate; HRAT: heart rate corresponding to the second ventilatory threshold; HRpeak: peak heart rate; TD: total time spent in the test;
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%HRpeakAT: HRAT percentage in relation to HRpeak.
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Post-training p
Median (Q1-Q3) Median (Q1-Q3) 115 (115-130)
130 (115-145)
0.048
Cadencepeak (bpm)
145 (130-160)
160 (145-160)
0.024
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CadenceAT (bpm)
CadenceAT: cadence corresponding to the anaerobic threshold;
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Cadencepeak: highest cadence reached on the aquatic test.
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S1744-3881(17)30127-5
DOI:
10.1016/j.ctcp.2017.06.001
Reference:
CTCP 739
To appear in:
Complementary Therapies in Clinical Practice
Received Date: 27 March 2017 Revised Date:
3 June 2017
Accepted Date: 4 June 2017
Please cite this article as: Costa RR, Reichert T, Coconcelli L, Simmer NM, Bagatini NatáCarvalho, Buttelli ACK, Bracht CláGomes, Stein R, Kruel LFM, Short-term water-based aerobic training promotes improvements in aerobic conditioning parameters of mature women, Complementary Therapies in Clinical Practice (2017), doi: 10.1016/j.ctcp.2017.06.001. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Title Page
ACCEPTED MANUSCRIPT Title: Water-based aerobic training of only five weeks promotes improvements in aerobic conditioning parameters of elderly women
Running Head: Water-based training and aerobic conditioning
Authors: 1
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1) Rochelle Rocha Costa (Costa, RR) - phone: 55 51 999090212 - email: [email protected] 1
2) Thais Reichert (Reichert, T) - phone: 55 51 982433007 - email: [email protected] 1
3) Leandro Coconcelli (Coconcelli, L) - phone: 55 51 982870056 - email: [email protected] 1
4) Nicole Monticelli Simmer (Simmer, NM) - phone: 55 51 993213113 - email: [email protected] 1
5) Natália Carvalho Bagatini (Bagatini, NC) - phone: 55 51 992154443 - email: [email protected] 1
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6) Adriana Cristine Koch Buttelli (Buttelli, ACK) - phone: 55 51 999071199 - email: [email protected] 1
7) Cláudia Gomes Bracht (Bracht, CG) - phone: 55 51 996222433 - email: [email protected] 2
8) Ricardo Stein (Stein, R) - phone: 55 51 997073321 - email: [email protected] 1
Affiliations:
1
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9) Luiz Fernando Martins Kruel (Kruel, LFM) - phone: 51 55 998063309 - email: [email protected]
Federal University of Rio Grande do Sul - School of Physical Education - 750 Felizardo
Street - Porto Alegre City - Rio Grande do Sul State – Brazil; 2
Hospital de Clínicas de Porto Alegre - 2350 Ramiro Barcelos Street - Porto Alegre City - Rio
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Grande do Sul State – Brazil
Affiliation where the research was conducted: Federal University of Rio Grande do Sul - School of Physical Education - 750 Felizardo Street - Porto Alegre City - Rio Grande do Sul State –
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Brazil.
Corresponding Author: Rochelle Rocha Costa.
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Exercise Research Laboratory - 750 Felizardo Street – Postal Code 90690-200 Porto Alegre, RS, Brazil Telephone number: 0055(51)3308 5820 - FAX 0055(51)3308 5817 e-mail: [email protected] Acknowledgements
We acknowledge financial support from CAPES, CNPq and FIPE-HCPA.
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Title: Short-term water-based aerobic training promotes improvements in aerobic
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conditioning parameters of mature women
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Running head: Water-based training and aerobic conditioning
4
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5 ABSTRACT
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Aging is accompanied by a decrease in aerobic capacity. Therefore, physical training has
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been recommended to soften the effects of advancement age. The aim of this study was to
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assess the effects of a short-term water-based aerobic training on resting heart rate (HRrest),
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heart rate corresponding to anaerobic threshold (HRAT), peak heart rate (HRpeak), percentage
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value of HRAT in relation to HRpeak and test duration (TD) of mature women. Twenty-two
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women (65.91 ± 4.83 years) were submitted to a five-week water-based interval aerobic
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training. Aerobic capacity parameters were evaluated through an aquatic incremental test.
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After training, there was an increase in TD (16%) and HRAT percentage in relation to HRpeak
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(4.68%), and a reduction of HRrest (9%). It is concluded that a water-based aerobic interval
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training prescribed through HRAT of only five weeks is able to promote improvements in
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aerobic capacity of mature women.
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Keywords: Aging, aerobic training, aquatic environment, heart rate, anaerobic threshold.
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INTRODUCTION Mature population has been showing an exponential growing worldwide (United
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Nations, 2009). According to United Nations (UN) data, the mature population currently
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represent 12.3% of the world population and, projections indicate that in the year of 2050
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they will represent 22%, including overcoming the number of young people. These data
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demonstrate the importance of investigations performed in the aging field.
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Aging is accompanied by a series of alterations in the organism, among them, we can
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highlight the decrease of aerobic capacity: it is estimated that a reduction of 10% by decade
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of life occurs from 20 years old (Fleg et al., 2005). This process is extremely relevant once
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aerobic capacity is related to functional capacity and is an independent predictor of mortality
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(Myers et al., 2015). Thus, stimulating the maintenance or even increasing the levels of
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aerobic capacity of mature individuals is fundamental in order to increase the capacity to
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accomplish daily life activities and to help to decrease mortality in this population.
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Aiming to promote improvements in aerobic capacity, aerobic training has been
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widely recommended. Within this context, water-based aerobic training gets highlighted for
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providing physical exercise practice with lower joint impact (Alberton et al., 2013; Alberton
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et al., 2014) and lower levels of arterial blood pressure and heart rate due to the lower
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sympathetic and adrenergic activation and to the suppression of rennin-angiotensin system
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(Pendergast et al., 2015). In this way, water-based aerobic training is performed with greater
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cardiovascular and osteoarticular safety, decreasing injury risk (Chu & Rodes, 2001) and
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making the activity interesting for mature people. Although aquatic environment shows these
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beneficial characteristics, only two studies investigated the effects of water-based aerobic
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training on aerobic capacity in the mature population (Takeshima et al. 2002, Bocalini et al.
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2008). In both studies, the authors observed gains in peak oxygen consumption of mature
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women submitted to a combined training (strength and aerobic) of 12 weeks of duration (12
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and 42%, respectively). Moreover, Takeshima et al. (2002) verified an increase of 20% in
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oxygen consumption corresponding to anaerobic threshold (VO2AT). Oxygen consumption is
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the best aerobic capacity representative (gold standard) and aerobic training prescription by
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means of anaerobic threshold can be determined through the ventilatory method during a
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cardiopulmonary exercise test (Delevatti et al., 2015). However, the availability of a gas
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analyzer is needed, which limits its applicability in the real world. Faced with that, the
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method based on the heart rate deflection point (HRDP) for training prescription has been
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gaining prominence for being easy applicable, low cost and associated with the anaerobic
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threshold determined by the ventilatory method (Alberton et al. 2013a; Delevatti et al. 2015;
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Kanitz et al. 2015; Pinto et al., 2016). HRDP method is based on the relationship between
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heart rate (HR) and intensity during an incremental exercise testing: this relationship is
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curvilinear (Kanitz et al., 2015). The point in which there is a break of the linear relationship
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(HRDP) is associated with the anaerobic threshold. In this way, this kind of test allows to
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asses several parameters related to aerobic capacity (resting HR, HR corresponding to
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anaerobic threshold, peak HR, among others) with a greater practical applicability in clubs
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and gyms, for being low cost and time-efficient, once that more than one individual can be
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evaluated at the same time.
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Thereby, the purpose of the present study was to assess the effects of a short-term
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water-based aerobic training on resting HR (HRrest), HR corresponding to anaerobic threshold
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(HRAT), peak HR (HRpeak), HRAT percentage in relation to HRpeak and test duration in mature
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women.
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METHODS
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Experimental design
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This is a study of exercise training intervention.
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Participants Twenty-three mature women who were initially sedentary (non-practitioners of
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systematized exercise in the previous three months), aged between 60 and 75, non-smoking
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and free from cardiovascular diseases (with the exception of controlled hypertension)
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participated in the study. Previously to the study entry, all participants performed a complete
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medical evaluation (clinical history, physical exam, 12-lead resting electrocardiogram and an
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exercise incremental test), signing an informed consent form in duplicate. The study was
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approved by the Ethics Committee of the Federal University of Rio Grande do Sul (UFRGS)
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and by the Clínicas Hospital of Porto Alegre (140547).
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Procedures
Participants attended the Swimming Center of the Physical Education, Physiotherapy
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and Dance School (ESEFID) of UFRGS in five occasions previously to the beginning of the
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water-based aerobic training. On the first visit, the volunteers received information about the
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study procedures, filled an anamnesis and signed the informed consent form. On the second
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visit, body mass (BM) and height measurements were made, and a first familiarization
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session to the aquatic environment was conducted, as also to the exercises that would be
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subsequently performed in the aerobic training protocol. On the third visit, the participants
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accomplished a second familiarization session to the aquatic environment, as also to the
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incremental test procedures and to the heart rate monitor equipment. On this occasion the
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incremental tests in aquatic and land environments were scheduled. The incremental test in
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aquatic environment was performed on the fourth visit. At the end of this test, the land
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incremental tests (on treadmill) were scheduled, which were performed on the fifth visit. It is
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important to highlight that between all visits a minimum interval of 72 hours was given. All
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participants were oriented to not drastically alter their feeding habits and to not perform
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additional physical activities (as exercise), to the ones prescribed in the proposed aerobic
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training, during the five weeks of intervention. Besides that, they were also oriented to inform
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the researchers in case of alteration in their daily use medication through the study period.
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Incremental test in aquatic environment
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Incremental tests in aquatic environment were conducted before the beginning of the
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training sessions and after the end of five weeks, in the pool of the Swimming Center of
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ESEFID/UFRGS. Tests were accomplished in controlled conditions, with water temperature
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between 29 and 31 °C, adopting immersion depth between the height of xiphoid process and
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shoulders of each participant.
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Previously to the beginning of each test, using a HR monitor, participants remained
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immersed, in orthostatic position, in silence and in absolute rest during five minutes and the
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lower HR value observed during this period was registered as HRrest. For the protocol of the incremental test, which was accompanied by a trained
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physician, the stationary run exercise was adopted, starting with warming-up of three minutes
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in the cadence of 85 beats per minute (bpm), with subsequently increments of 15 bpm in the
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cadence at each two minutes, until the participants reached self-reported exhaustion. Besides
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that, range of motion was controlled at 90º of hip and knee flexion, and the test was
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interrupted when the volunteers could not maintain the exercise in the rhythm dictated by the
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cadences. HR was collected at each 10 seconds for the determination of HRDP, which was
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used for the HRAT identification, once that this point is strongly correlated with the anaerobic
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threshold determined by the ventilatory method (Alberton et al., 2013a). To do so, a HR
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monitor (POLAR, FT1, Finland) and a standardized form for recording the data were used.
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For the determination of the execution rhythm of the exercise, a metronome (KORG, MA-30,
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Japan) was utilized. Collected data, in the sampling rate of 10s, were then plotted in a
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dispersion graph and thus HRDP was determined, according to the methodology
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demonstrated in the study of Alberton et al. (2013a). The determination of the point referring
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to HRAT was made in an independent and blinded manner by three experienced researchers.
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Discordances were decided by consensus when possible, or alternatively the median of the
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three values was adopted. The cadence in which each participant was exercising at the
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moment corresponding to anaerobic threshold was determined as CadenceAT.
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At the end of the test, total time spent (test duration - TD) was registered in minutes,
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until the voluntary exhaustion of the participant or the inability in maintaining the correct
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range of motion of the movement within the determined cadence. The highest HR value near
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the end of the test was adopted as HRpeak in this study. With this values, percentage value of
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HRAT corresponded to HRpeak was determined (%HRpeakAT). The last cadence performed in
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each test was registered as Cadencepeak, representing the greater cadence reached by each
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participant.
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Incremental test in land environment
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Incremental test in land was performed in order to obtain HRpeak in land environment
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(HRpeak_land) and was used for sample characterization. For this, a treadmill (INBRAMED,
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ATL, Brazil), with a 0.01 km.h-1 resolution for speed and 1% for inclination, and the same
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HR monitor equipment adopted in the aquatic environment were used. All women remained
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seated on a chair on the treadmill during five minutes, allowing the stabilization of the HRrest
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and enabling the instructions for the test. The Bruce protocol (Bruce et al., 1973) was
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adopted, in which increments of speed and inclination were conducted at each three minutes.
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HR was collected and registered at each 30s. The test was interrupted when the volunteer
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indicated her exhaustion, through a manual sign previously arranged and at this moment HR
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was finally registered. The greater HR value reached near the end of the test was adopted as
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HRpeak_land.
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Both tests, in aquatic and land environment, were performed during the morning shift,
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and participants were instructed to maintain the use of their daily medication at the usual
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time. Furthermore, they were instructed to not feed themselves in the three hours previously
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to the tests, and to not attend in night fasting, besides not consuming stimulants and not
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practicing intense physical activities in the 24 hours before the tests (Cooke, 1996).
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164 165
Water-Based Aerobic Training
Aerobic training sessions were performed at the pool of the Swimming Center of
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ESEFID/UFRGS and instructed by a Physical Education professional with previous
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experience in water-based aerobic bouts, monitored by an assistant, aiming to ensure that the
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target intensity was reached. Total training period was five weeks, during which the
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participants performed two weekly sessions of 45 minutes each. Whenever necessary,
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recovery sessions were offered within the same week for those participants who might have
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missed some session. Besides that, no alteration in daily medication was notified during the
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study period. All sessions was composed by an initial warm-up, with duration of seven
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minutes, main part (composed by aerobic training), with duration of 30 minutes, and a cool
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down, with duration of eight minutes.
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In the main part of the training sessions, four exercises were adopted, bilaterally
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performed in a combined manner (each lower limbs exercise was associated with an upper
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limbs exercise). The exercises are demonstrated on Figure 1.
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****Figure 1 near here****
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Training intensity control was performed with the use of HR monitors, being
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controlled by a zone corresponding to HRAT. Training was conducted adopting the interval
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method, alternating four minutes in the intensity corresponding to HR range of 90 and 95%
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HRAT and one minute between 80 and 85% HRAT (Table 1).
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*****Table 1 near here****
Statistical Analysis
Scalar variables data are presented as means and standard deviations. On the other
191
hand, ordinal data (CadenceAT and Cadencepeak) are presented as median and interquartile
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interval. Normality of dependent variables data was tested adopting Shapiro-Wilk test. After
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the normality confirmed, the comparison of the data in pre- and post-training moments
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(temporal analysis) was performed by T-Test for paired samples. The comparison of medians
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of cadences at pre- and post-training was performed by Wilcoxon Test. Both analyses
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adopted a significance level of 5% (α = 0.05). Statistical procedures were performed in the
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Software SPSS version 22.0.
201 202 203 204 205 206
The whole sample (n = 23) finished the five weeks of water-based aerobic training,
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RESULTS
showing 100% adherence to the proposed protocol (10 sessions). Sample characterization data, including age, body mass, height and body mass index
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of the mature women who participated in the study are presented on Table 2.
****Table 2 near here****
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In regard to the temporal behavior of the dependent variables, it was observed that
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HRrest showed a significant reduction of 8 bpm after five weeks of aerobic training in aquatic
209
environment. In contrast, HRAT and HRpeak did not suffer any significant alterations over this
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period. The TD showed significant increase of 1 min and 49 seconds in the comparison
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between the tests performed in the beginning of the training and after the fifth week,
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indicating that the participants took more time to reach exhaustion. In addition, %HRpeakAT
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suffered a significant increment of 4.68% after the five weeks of training. The CadenceAT
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was improved in 1 cadence (15 bpm) from pre- to post-training, such as the Cadencepeak (15
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bpm after 5 weeks of training). Such data and the statistical significance of the time
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comparison are presented on Tables 3 and 4.
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****Table 3 near here**** ****Table 4 near here****
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DISCUSSION
The main finding of the present study was that only five weeks of water-based aerobic
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training were enough for promoting an improvement of aerobic capacity of mature women,
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evidenced by the decrease of HRrest, increase of test duration and %HRpeakAT.
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Aging process is associated to an increase of sympathetic nervous system activity
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(Fiuza-Luces et al., 2013), reflecting on a tendency of increased HRrest. This alteration in
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cardiovascular system demands concern, once increased HRrest is considered a risk factor for
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mortality (increased risk of 16% at each 10 bpm) (Jensen et al., 2013). In contrast, this
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deleterious effect of aging can be minimized by aerobic training: a decrease of about 1 bpm
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at each training week is expected in sedentary individuals, mainly in the first 10 weeks
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(Wilmore et al., 2010). In fact, the interval aerobic training proposed in the present study
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promoted a reduction of HRrest, which was even higher than expected (1.6 bpm per week).
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This is a finding of clinical relevance, since it represents a decrease of approximately 13% in
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all-cause mortality risk (Jensen et al., 2013).
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The results of the present study corroborate the findings of Bocalini et al. (2008), who
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observed a significant reduction of HRrest from 92 to 83 bpm after 12 weeks of water-based
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aerobic training in mature women. On the other hand, Takeshima et al. (2002) did not
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verified significant alterations in HRrest of mature women after 12 weeks of water-based
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aerobic training. Possibly, the results found by Takeshima et al. (2002) may have been
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attributed to the lower HRrest of the participants in the pre-training status (77bpm), which
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reduced the possibility of improvement of these individuals, unlike the data of our study
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participants and the study of Bocalini et al. (2008).
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On the other hand, we did not observe a significant difference in HRAT after
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intervention. Only two previous studies investigated the effects of water-based aerobic
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training on parameters corresponding to AT (Pinto et al., 2015; Takeshima et al., 2002).
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Although these studies did not enroll exclusively mature individuals, Pinto et al. (2015)
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observed increments in VO2AT of postmenopausal women (7 to 11%) and Takeshima et al.
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(2002) of mature women after 12 weeks of training (20%). It is speculated that the absence of
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adaptation occurred in our study may be related to the shorter intervention period (five weeks
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versus12 weeks) and to the lower training intensities (90-95% HRATversus100% HRAT) used.
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Maintenance was also observed in HRpeak after training. Corroborating our result,
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Takeshima et al. (2002) did not find adaptations in HRpeak after 12 weeks of water-based
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aerobic training. Indeed, little or no adaptation is expected in this outcome after an aerobic
254
program (Wilmore et al., 2010). It is highlighted that the HRpeak reached in the incremental
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test in aquatic environment was much lower than the one obtained in land (133 versus 145
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bpm). This behavior was already expected and can be explained by the physical properties of
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aquatic environment. During immersion, hydrostatic pressure and thermoconductivity
258
increase pre load (venous return), causing an increment of blood volume in the central region
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of the organism (Arborelius et al., 1972, Pendergast et al., 2015). This hypervolemia causes
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an increase of the end-diastolic volume, which will promote an increase of stroke volume and
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cardiac output, with consequent HR reduction (Arborelius et al., 1972; Pendergast et al.,
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2015). Although alterations in HRAT an in HRpeak were not evidenced, the cadence in which
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these moments occurred was significantly increased after the 5 weeks of training. The
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maintenance of a same value of HR in greater cadences can be viewed as a favorable
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adaptation, indicating cardiorespiratory and metabolic economy in response to the increase of
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the external loads, which may be due to an improvement in the venous return and increase of
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the stroke volume. Another reasonable explanation is the possible increase in the strength
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levels after the 5 weeks of aquatic training, given that the exercises, even if prescribed in
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aerobic intensities, are performed against the resistance promoted by water, which can
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generate neuromuscular adaptations that favor to support higher intensities as those observed
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in the greater cadences.
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It is important to mention that a significant increase of test duration and %HRpeakAT
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after water-based aerobic training was observed. The augmentation of one minute in test
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duration represents that the mature women were able to support the exercise for a longer time
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and in greater intensities. Regarding to %HRpeakAT, it reflects that our sample of mature
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women were able to reach the anaerobic threshold in a HR percentage closer to HRpeak,
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showing an improvement in aerobic capacity after the proposed intervention. It is emphasized
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that the mature women presented a higher %HRpeakAT already at pre-training in comparison
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to studies performed on land environment, which assessed the percentage of a
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cardiorespiratory parameter in relation to the maximum (Chtara et al., 2005; Cadore et al.,
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2012a; Ferrari et al., 2013; Kanitz et al., 2015). This result may be explained by the
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augmentation of blood volume in the central region of the organism. Central hypervolemia
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causes an increase in alveolar pressure, which might result in an increased oxygen release in
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the bloodstream, promoting a greater supply of oxygen to the tissues. In this way, in aquatic
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environment there is a greater energy supply through anaerobic route in comparison to land
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environment. A possible limitation of the present study is the absence of a control group. However,
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it is highlighted that this is an area where evidences are lacking, since that only two studies in
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the literature assessed the effects of water-based aerobic training on aerobic capacity of
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mature women. In this sense, our findings are innovative, as they demonstrate that only five
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weeks of water-based aerobic training prescribed through HRAT promotes improvements in
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aerobic capacity of mature women, improving their capacity to accomplish their daily life
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activities and decreasing their mortality risk. Finally, we presented a test of low cost and easy
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applicability that, besides being used for training prescription, it also can be used in the
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evaluation of aerobic capacity parameters.
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CONCLUSION
A water-based aerobic interval training prescribed through HRAT of only five weeks is
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able to promote a significant reduction of HRrest and an increment of test duration and
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%HRpeakAT, showing an improvement in aerobic capacity of mature women.
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ACCEPTED MANUSCRIPT REFERENCES
312 313 314 315
Alberton, C.L., A.C. Kanitz, S.S. Pinto, A.H. Antunes, P. Finatto, E.L. Cadore and L.F.M. Kruel. 2013a. Determining the anaerobic threshold in water aerobic exercise: a comparison between the heart rate deflection point and the ventilatory method. Journal of Sports Medicine and Physical Fitness 53: 358-67.
316 317 318 319
Alberton, C.L., M.P. Tartaruga, S.S. Pinto, E.L. Cadore, A.H. Antunes, P. Finatto and L.F Kruel. 2013. Vertical ground reaction force during water exercises performed at different intensities. International Journal of Sports Medicine 34(10): 881-87. doi: 10.1055/s-00321331757
320 321 322 323
Alberton, C.L., S.S. Pinto, E.L. Cadore, M.P. Tartaruga, A.C Kanitz, A.H. Antunes, P. Finatto and L.F.M. Kruel. 2014. Oxygen uptake, muscle activity and ground reaction force during water aerobic exercises. International Journal of Sports Medicine 35: 1161-69. doi:10.1055/s-0034-1383597
324 325
Arborelius Jr. M., U. I. Ballidin, B. Lilja and C. E. Lundgren.1972.Hemodynamic changes in man during immersion with the head above water. Aerospace medicine 43(6), 592-98.
326 327 328
Boccalini, D.S., AJ.Serra, N. Murad and R.F. Levy. 2008. Water-versus land-based exercise effects on physical fitness in older women. Geriatrics & Gerontology 8: 265-71. doi: 10.1111/j.1447-0594.2008.00485.x
329 330 331
Bruce, R.A., F. Kusumi and D. Hosmer. 1973. Maximal oxygen intake and nomographic assessment of functional aerobic impairment in cardiovascular disease. American Heart Journal 85:546–62.
332 333 334 335
Cadore, E. L., M. Izquierdo, C. L. Alberton, R. S. Pinto, M. Conceição, G. Cunha, et al. 2012. Strength prior to endurance intra-session exercise sequence optimizes neuromuscular and cardiovascular gains in elderly men. Experimental Gerontology 47(2), 164-69.doi:10.1016/j.exger.2011.11.013
336 337 338 339
Chtara, M., K. Chamari, M. Chaouachi, A. Chaouachi, D. Koubaa, Y. Feki, G.P. Millet and M. Amri. 2005. Effects of intra-session concurrent endurance and strength training sequence on aerobic performance and capacity. British Journal of Sports Medicine 39(8), 555-60. doi: 10.1136/bjsm.2004.015248
340 341 342
Chu, K.S., and E.C. Rhodes. 2001. Physiological and cardiovascular changes associated with deep water running in the young. Possible implications for the elderly. Sports Medicine 31(1): 33-46.
343 344 345
Cooke, C.B., R. Eston and T. Reilly. 1996. Metabolic rate and energy balance. Kinanthropometry and exercise physiology laboratory manual. London: E & FN Spon p.175-95.
346 347 348 349
Delevatti, R.S., A.C. Kanitz, C.L. Alberton, P.D. Pantoja, E.C. Marson, C.D.F. Pinho, S.C. Lisboa, L.P. Bregagnol and L.F.M. Kruel. 2015. Heart Rate Deflection Point as an Alternative Method to Identify the Anaerobic Threshold in Patients with Type 2 Diabetes. Apunts. Medicina de l'Esport 50(188):123-28.doi:10.1016/j.apunts.2015.05.001
350
Ferrari, R., L. F. M. Kruel, E. L. Cadore, C. L. Alberton, M. Izquierdo, M. Conceição, et al.
AC C
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M AN U
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311
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2013. Efficiency of twice weekly concurrent training in trained elderly men. Experimental Gerontology 48(11), 1236-42.doi: 10.1016/j.exger.2013.07.016
353 354
Fiuza-Luces, C., N. Garatachea, N. A. Berger, & A. Lucia. 2013. Exercise is the real polypill. Physiology 28(5), 330-58.doi:10.1152/physiol.00019.2013
355 356 357
Fleg, JL., C.H. Bos. A.G. Morrel, L.J. Brant, LA. Talbot, J.G. Wright and E.G. Lakatta. 2005. Accelerated Longitudinal Decline of Aerobic Capacity in Healthy Older Adults. Circulation 112(5): 674-82. doi: 10.1161/CIRCULATIONAHA.105.545459
358 359 360
Jensen, M.T., P. Suadicani, H.O. Hein and F. Gyntelberg. 2013. Elevated resting heart rate, physical fitness and all-cause mortality: a 16-year follow-up in the Copenhagen Male Study. Heart 99: 882–87.doi:10.1136/heartjnl-2012-303375
361 362 363 364
Kanitz, A. C., R. S. Delevatti, T. Reichert, G. V. Liedtke, R. Ferrari, B. P. Almada, et al. 2015. Effects of two deep water training programs on cardiorespiratory and muscular strength responses in older adults. Experimental Gerontology 64, 5561.doi:10.1016/j.exger.2015.02.013
365 366 367
Mekjavic, I. B. and J. Bligh. 1989. The increased oxygen uptake upon immersion. European journal of applied physiology and occupational physiology 58(5), 556-62.doi: 10.1007/BF02330712
368 369 370 371
Myers, J., P. McAuley, C. J. Lavie J. P. Despres, R. Arena & P. Kokkinos. 2015. Physical activity and cardiorespiratory fitness as major markers of cardiovascular risk: their independent and interwoven importance to health status. Progress in cardiovascular diseases, 57(4), 306-14. doi:10.1016/j.pcad.2014.09.011
372 373 374
Pendergast, D. R., R. E. Moon, J. J. Krasney, H. E. Held, & P. Zamparo. 2015. Human physiology in an aquatic environment.. Comprehensive Physiology 5: 1705-50. doi: 10.1002/cphy.c140018
375 376 377 378
Pinto, S. S., C. L. Alberton, N. C Bagatini, P. Zaffari, E. L. Cadore, R. Radaelli, et al. 2015. Neuromuscular adaptations to water-based concurrent training in postmenopausal women: effects of intra session exercise sequence. Age 37(1), 1-11.doi: 10.1007/s11357-015-97517
379 380 381 382
Pinto, S. S., R. M. Brasil, C. L. Alberton, H. K. Ferreira, N. C. Bagatini and J. Calatayud, & J. C. Colado. 2016. Noninvasive Determination of Anaerobic Threshold Based on the Heart Rate Deflection Point in Water Cycling. The Journal of Strength & Conditioning Research 30(2): 518-24.
383 384 385
Takeshima, N., M.E. Rogers, E. Watanabe, W.F. Brechue, A. Okada, T. Yamada, et al. 2002. Water-Based Exercise Improves Health-Related Aspects of Fitness in Older Women. Medicine and Science in Sports and Exercise 34(3): 544-51.
386 387 388
United Nations. 2009. World Population Ageing 2009. http://www.un.org/esa/population/publications/WPA2009/WPA2009_WorkingPaper.pdf (accessed December 20, 2016).
389 390
Wilmore, J.H., D.L. Costill and W.L. Kenney. Physiology of Sports and Exercise. 4a Edition. United States: Human Kinetics, 2010.
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ACCEPTED MANUSCRIPT Table 1 – Water-based aerobic training. Duration
4 min 6
1 min
Exercises 1) Hip flexion/extension + elbow flexion/extension 2) Hip flexion/extension + shoulder horizontal flexion/extension 3) Hip flexion/extension + elbow flexion/extension 4) Hip flexion/extension + shoulder horizontal flexion/extension 1) Knee flexion/extension + elbow flexion/extension
Duration of each exercise
Intensity
1 min
90 to 95% HRAT
1 min
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HRAT: Heart rate corresponding to anaerobic threshold.
Total Duration
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Sets
80 to 85% HRAT
30 min
ACCEPTED MANUSCRIPT Table 2 – Baseline sample characterization. Mean ± SD
Minimum Maximum
65.91 ± 4.83
60
74
BM (kg)
74.16 ± 13.70
55.30
110.70
Height (m)
1.57 ± 0.06
1.45
1.68
HRpeak_land (bpm)
145 ± 18.09
112
181
BMI (kg.m-2)
30.03 ± 4.97
22.59
43.15
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Age (years)
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BM: body mass; HRpeak_land: peak heart rate in land
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environment; BMI: body mass index.
ACCEPTED MANUSCRIPT Table 3 – Dependent variables at pre- and post-training. Pre-Training
Post-training p (Mean ± SD)
HRrest (bpm)
89 ± 8.60
81 ± 9.54
<0.001
HRAT (bpm)
117 ± 13.51
121 ± 18.98
0.230
HRpeak (bpm)
133 ± 16.29
130 ± 21.34
0.322
TD (min)
9.51 ± 2.92
11.00 ± 3.03
0.044
%HRpeakAT (%)
87.79 ± 5.90
92.47 ± 3.78
0.005
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(Mean ± SD)
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HRrest: resting heart rate; HRAT: heart rate corresponding to the second ventilatory threshold; HRpeak: peak heart rate; TD: total time spent in the test;
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%HRpeakAT: HRAT percentage in relation to HRpeak.
ACCEPTED MANUSCRIPT Table 4 - Cadence data at pre- and post-training. Pre-Training
Post-training p
Median (Q1-Q3) Median (Q1-Q3) 115 (115-130)
130 (115-145)
0.048
Cadencepeak (bpm)
145 (130-160)
160 (145-160)
0.024
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CadenceAT (bpm)
CadenceAT: cadence corresponding to the anaerobic threshold;
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Cadencepeak: highest cadence reached on the aquatic test.
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