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A minimal dose approach to resistance training for the older adult; the prophylactic for aging
Experimental Gerontology 99 (2017) 80–86
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Experimental Gerontology journal homepage: www.elsevier.com/locate/expgero
Mini review
A minimal dose approach to resistance training for the older adult; the prophylactic for aging
MARK
James P. Fishera,⁎, James Steelea, Paulo Gentilb, Jürgen Giessingc, Wayne L. Westcottd a
Southampton Solent University, East Park Terrace, Southampton, UK Faculdade de Educação Física e Dança, Universidade Federal de Goias, Goiânia, Brazil c InstitutfürSportwissenschaft, Universität Koblenz-Landau, Germany d Quincy College, Quincy, MA, USA b
A R T I C L E I N F O
A B S T R A C T
Editor: Christiaan Leeuwenburgh
A plethora of research has supported the numerous health benefits of resistance training as we age, including positive relationships between muscular strength, muscle mass and reduced all-cause mortality. As such, resistance training has been referred to as medicine. However, participation and adherence remains low, with time constraints and perceived difficulty often cited as barriers to resistance training. With this in mind, we aimed to summarise the benefits which might be obtained as a product of a minimal dose approach. In this sense, participation in resistance training might serve as a prophylactic to delay or prevent the onset of biological aging. A short review of studies reporting considerable health benefits resulting from low volume resistance training participation is presented, specifically considering the training time, frequency, intensity of effort, and exercises performed. Research supports the considerable physiological and psychological health benefits from resistance training and suggests that these can be obtained using a minimal dose approach (e.g. ≤60 min, 2 d-wk− 1), using uncomplicated equipment/methods (e.g. weight stack machines). Our hope is that discussion of these specific recommendations, and provision of an example minimal dose workout, will promote resistance training participation by persons who might otherwise have not engaged. We also encourage medical professionals to use this information to prescribe resistance exercise like a drug whilst having an awareness of the health benefits and uncomplicated methods.
Keywords: Strength Health Longevity Quality of life Behaviour Adherence
1. Introduction There is an abundance of evidence highlighting the physiological benefits of resistance training (RT); including decreased gastrointestinal transit time (reducing the risk of colon cancer (Koffler et al., 1992)), increased metabolic rate (Campbell et al., 1994), reduction in low back pain (Bruce-Low et al., 2012), increased bone mineral density (Huovinen et al., 2016), reduced blood pressure (Westcott et al., 2009), and improved muscle quality and insulin sensitivity in persons with type-2 diabetes (Brooks et al., 2007). More so than these specific health benefits, evidence has supported that muscular strength (Newman et al., 2006; Ruiz et al., 2008) and muscle mass (Srikanthan and Karlamangla, 2014) are predictors of longevity and reduction in allcause mortality. Whilst increased strength and muscle mass are often goals of RT, and justifiably so due to the health benefits of these adaptations, it was recently noted that a primary objective of persons undertaking RT is “to have a biological age equal to, or lower than, our
chronological age” (Fisher et al., 2014a). This is evidently a realistic objective based on the following studies. Melov et al. (2007) reported that following 6 months of RT participants with an average age of 68 years showed mitochondrial characteristics similar to persons with a mean age of 24 years. Candow et al. (2011) reported that 22 weeks of RT eliminated the strength and muscle mass deficit of older men when compared to 18–31-year-old men. And Yarasheski et al. (1993) reported that basal fractional rate of muscle protein synthesis, whilst lower in the elderly compared to young men and women; increased to a comparable rate following only 2 weeks of RT. Combined, these health benefits are not only important for all members of the population for healthy aging, but might play a particularly crucial role in older adults given the associated sarcopenia and dynapenia, as well as risk of falls and fractures (Tinetti et al., 1988).
⁎
Corresponding author. E-mail addresses: james.fi[email protected] (J.P. Fisher), [email protected] (J. Steele), [email protected] (P. Gentil), [email protected] (J. Giessing), [email protected] (W.L. Westcott). http://dx.doi.org/10.1016/j.exger.2017.09.012 Received 29 June 2017; Received in revised form 24 August 2017; Accepted 13 September 2017 Available online 28 September 2017 0531-5565/ © 2017 Elsevier Inc. All rights reserved.
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2. Methods
(mean = 55 ± 10 years) and females (mean = 55 ± 11 years) as a result of performing 2 weekly workouts with an average of only 5 multijoint exercises per workout. Mean strength increases by exercise were: pull-down = 68 and 91%; chest press = 55 and 59%; seated row = 65 and 81%; overhead press = 39 and 58%; and leg press = 38 and 59%, for males and females, respectively. Each exercise was performed on a standard weight-stack resistance machine for only a single set each (equating to approximately 12 min per workout). Westcott et al. (2009) reported data from 1619 males and females aged between 21 and 80 years who performed 10 weeks of combined aerobic and resistance training 1 (n = 81), 2 (n = 845) or 3 (n = 693) days/week. Each exercise session was completed within 1 h, with only 20 min of RT; a single set of 10 standard weight-stack resistance machines performed to volitional fatigue for between 8 and 12 repetitions. All groups showed significant improvements in systolic and diastolic blood pressure with progressive improvements in body fat reduction and muscle mass increase aligned with greater training frequency.1 The authors also reported a drop-out rate of only 9%, and adherence of 84%, 83% and 80% for the 1, 2 and 3 days/week groups, respectively. Most recently Steele et al. (2017) reported significant increases in strength and functional tasks (e.g. a stair climb task, carrying of shopping basket task, and chair rise task) and wellbeing following 6 months of high effort, twice weekly resistance training using a single set of leg press, chest press, seated row, knee extension, knee flexion, trunk extension and trunk flexion exercises. However, despite these very positive findings we should consider that some studies have produced equivocal data. For example, Walker et al. (2017) considered strength, muscle activation and muscle mass for the quadriceps of older adults (64–75 years) performing reduced RT. Following 12 weeks of 2 days/week RT, participants were divided in to those continuing at the same frequency and those reducing training to only 1 day/week, for a further 24 weeks. Both strength and muscle activation continued to increase in both groups with no significant between-group differences. However, the authors reported reductions in CSA for the reduced frequency group. It might be that muscle function can be sustained with low frequency training whereas muscle mass requires RT of 2 days/week to be maintained.
Position stands by the likes of the American College of Sports Medicine (ACSM) might be interpreted to support the necessity for complicated, high-volume RT programmes (Ratamess et al., 2009), which might serve to deter engagement and adherence. Indeed, time constraints and perceived difficulty are often cited as barriers to RT (Trost et al., 2002; Winett et al., 2009). As such, we aimed to assess what benefits might be attained from, and what might constitute, a minimal dose approach to RT. For this commentary, we considered some of the seminal literature considering a variety of positive physiological and psychological health adaptations resulting from RT, including those where details of volume and frequency were included/ could be calculated. It is worth noting that this is not an exhaustive review and word constraints prevent greater analysis. However, this article is intended to determine the approximate minimal necessary volume and frequency to identify a ‘minimal dose’ of RT for the evidenced health benefits. 2.1. Dosage Whilst emphasis has been placed on the considerable health benefits of RT, many people might not realise that these positive responses have been attained using a low to moderate dose of RT. For example, in the above studies participants performed RT for low- (~ 20 min, to ~ 35 min (Brooks et al., 2007)) to moderate- (~ 40 min (Campbell et al., 1994) and ~60 min (Huovinen et al., 2016)) volumes, 3 days/week. Notably, time might be saved by performing only multi-joint exercises, as opposed to the addition of single joint exercises. For example, Gentil et al. (2016) suggested that use of only multi-joint exercises appears to produce similar increases in strength and muscle mass as higher volumes of training through the addition of single-joint exercises. Furthermore, whilst some authors have reported more favourable increases in strength and hypertrophy by performing multiple sets of an exercise (Krieger, 2009; Krieger, 2010; Schoenfeld et al., 2016), in older adults, there seems to be no consistent benefit beyond single-set RT. For example, Cannon and Marino (2010) reported that younger and older women showed similar increases in knee extension muscle strength and size when performing RT with one or three sets per exercise after 10 weeks, with no significant interactions between age or number of sets and time. Abrahin et al. (2014) found similar gains in functional tests, as well as strength and muscular endurance of older women after performing 24 sessions with either one or three sets per exercise. Galvão and Taaffe (2005) compared the effects of 20 weeks of one vs. three sets per exercise and found inconsistent results. The high-volume group showed greater increases in maximal strength for seated row, triceps extension, and leg extension as well as muscular endurance in the chest press and leg press. However, there were no between-group differences in biceps curl, chest press, leg press and leg curl maximum strength as well as in isometric and isokinetic knee extensor peak torque. Furthermore, improvement in functional tests and body composition also did not differ between groups. More recently, Radaelli et al. (2014) compared the effects of 20 weeks of one vs. three sets of resistance exercise in older women and reported favourable increases for the multiple set group for knee extension 1-repetition maximum (1RM), but no between-group differences for increases in elbow flexion 1RM. In fact, a meta-analysis by Silva et al. (2014) suggested that variance in load (55–84% 1RM), volume (1–6 sets), or frequency (1–3 days/week) did not produce significantly different strength increases in adults over 55 years. In further support of the proposed low-volume approach for strength increases; Koffler et al. (1992) used a single set for upper body exercises and 2 sets for lower body exercises reporting strength increases of (mean ± standard deviation) 41 ± 5% (p < 0.001) and 45 ± 6% (p < 0.001), respectively. Fisher et al. (2014b) reported significant (p < 0.001 to p = 0.014) strength increases in older males
2.2. Additional health benefits Further benefits to RT have been identified including myokine release; hormones released by skeletal muscle tissue which serve to combat metabolic disorders (Schnyder and Handschin, 2015), improved cognitive functioning (Nagamatsu et al., 2012), and an array of psychological health benefits including; a reduction of fear of falling in the frail elderly (Yamada et al., 2011), improved sleep quality in depressed older adults (Singh et al., 2005), reduced anxiety (Cassilhas et al., 2007), reduced depression (Singh et al., 1997) and improved selfesteem (Tsutsumi et al., 1998). Whilst some of these RT doses were also low- (≤ 60 min, 2 days/week (Nagamatsu et al., 2012; Yamada et al., 2011; Singh et al., 2005)) and moderate- (45–60 min, 3 days/week (Cassilhas et al., 2007; Singh et al., 1997; Tsutsumi et al., 1998)) in volume, other studies failed to provide sufficient details to determine a training time. Research has supported that the main motivator for older adults to participate in RT would be “…to feel good mentally and physically…” (Burton et al., 2016). Combined the psycho-social benefits and physiological adaptations outlined would serve to improve quality of life and encourage older adults to be more interactive and engaged in daily activities and socialisation.
1 It is worth acknowledging that an aerobic exercise component during the 1-hour session might have expedited positive blood pressure and body composition adaptations.
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differing reasons. Whilst it is difficult to individually determine at what point RT becomes excessive (i.e. an ‘overdose’) and thus; might incur negative side-effects, there is certainly evidence to suggest that too much exercise can result in overreaching (a short-term state preceding overtraining). Overreaching might result in a decreased immune system (often resulting in upper respiratory tract infections), a decrease in the testosterone: cortisol ratio (which might be indicative of imbalance in anabolic and catabolic physiological states) and psychological disturbances and negative affective states (Halson and Jeukendrup, 2004; Hooper et al., 1997). Whilst overreaching might be relatively common in athletic populations, and recovery appears reasonably brief (e.g. within 2 weeks), we suggest that this is something to be avoided in the lay population or older adults. Since these symptoms might also parallel short-term strength decreases, we feel it is important to draw attention to this since a common response to a decrement in strength is to do more training in an attempt to overcome this, rather than rest and recover. With this in mind, we propose that, in order to avoid excess, and as with medication, participants approach RT using a minimum dose that might later be adapted if necessary. We have presented evidence that uncomplicated resistance exercise (e.g. 3–10 weight-stack machines performed for a single set) at a low to moderate dosage (< 60 min, 2 days / week) might be all that is necessary to attain the aforementioned positive health adaptations. We recommend that this dose is within the capacity of all or most members of the population, particularly older adults who might benefit more from the physiological and psychological benefits. We hope this article provides the motivation to those who most need RT by improving their understanding of the dose demands, as well as serving to promote both the simplicity and potential health benefits of RT to medical professionals so that they might be confident to prescribe exercise like a drug. Furthermore, researchers might consider the efficacy of a low-volume, minimal dose approach in their RT studies to consider the efficacy in relation to additional positive adaptations.
2.3. Intensity of effort, adherence and supervision Perhaps the only caveat to such a minimal dose approach is the apparent need for participants to exercise to a high intensity of effort. In the studies detailed, the exercise protocols achieved more favourable adaptations where participants were required to lift a moderate to heavy load (e.g. 50–90% 1-repetition maximum; RM) and either exercise to momentary failure (e.g. where they could not complete another repetition despite attempting to do so) or complete multiple sets of each exercise permitting cumulative fatigue and higher effort in later sets. In some cases, favourable trainer:client supervision ratios supported the high intensity of effort, e.g. 1:1 (Fisher et al., 2014b; Steele et al., 2017) or 2:6 (Westcott et al., 2009). Certainly, evidence has previously supported greater increases in upper and lower body strength in a high supervision (1:5; trainer to athlete ratio) compared to a low supervision (1:25) group (Gentil and Bottaro, 2010). Indeed, the aforementioned study by Steele et al. (2017) permitted participants to continue unsupervised RT for a further 6 months after their initial 6 month supervised intervention. Data revealed that when unsupervised, RT produced similar strength and functional task outcomes to those who discontinued training entirely. Furthermore, supervision appears to improve adherence. For example, Arikawa et al. (2011) reported adherence rates of 95.4% and 64.5% during supervised and unsupervised periods of a RT intervention in overweight women. This is supported by Van Roie et al. (2015), who reported diminished adherence when participants were permitted to continue exercising following the end of a supervised intervention. In fact, only 11–21% of participants continued RT, with those discontinuing citing perceived lack of time as the most common reason (46%). As such, whilst the aforementioned study by Westcott et al. (2009) showed high adherence/low drop-out rates, this might be, at least partially, a product of participants attending supervised exercise sessions. In summary, whilst motivated persons might attain the necessary effort levels without such supervision, the previous studies by Steele et al. (2017), Arikawa et al. (2011) and Van Roie et al. (2015) suggest that supervision might be important for adherence and outcomes. The health benefits reported as a result of RT, along with the specific variables of the research interventions (e.g. exercises performed, volume, approximate time commitment, frequency, supervision ratio, and duration) are reported in Table 1. It is also worth clarifying that participants within the majority of studies exercised predominantly using standard weight-stack resistance machines. This serves to both save time by simply adjusting the load via the use of a pin rather than loading and unloading weight plates, and simplifies the training session potentially making it more appealing to persons less confident or inexperienced in a gym environment. Furthermore, data suggests that machine-based resistance might be safer than free-weight exercises (Kerr et al., 2010). We also suggest that bodyweight alternatives might exist should persons not have access to the resistance machines detailed. Certainly, evidence supports that muscular tension might be all that is necessary to increase muscle strength and size, even using simple isometric cocontraction (Maeo et al., 2013). However, because of the technical elements of bodyweight exercise we advocate supervision to retain good posture and avoid injury.
4. Practical application In the interests of clarity, a ‘minimal dose’ example workout would be to perform multi-joint exercises for the major muscle groups, e.g. chest press, leg press, and seated row. Supplementary, but non-essential exercises include the overhead press and pull-down exercises, where contraindications such as high blood pressure or limited shoulder mobility/impingement do not exist. Lower body single joint exercises should be included (e.g. leg curl and knee extension) if the leg press is unsuitable for any reason or as additional lower body exercises should there be a need to specifically target the knee extensors/flexors. Inclusion of lumbar extension, and abdominal flexion exercises should be included intermittently to reduce risk or severity of back pain (Bruce-Low et al., 2012), improve posture, and protect the spine and vital organs. Finally, evidence has shown that the cervical extensors are especially weak and as such including a neck extension exercise will serve to strengthen these muscles which, evidence suggests, plays a role in reduced injury risk (Fisher et al., 2016; Hislop et al., 2017). Academic support for the inclusion of each specific exercise is provided in Table 2. This selection of exercises serves to target the major muscle masses of the body and promote positive health adaptations. This workout might ideally be performed under direct supervision of a fitness professional to assess client suitability of these exercises, coach correct technique and provide encouragement which might serve to increase participant intensity of effort. However, without supervision this workout is still suitable for an inexperienced person, and might require only a single set of each exercise, performed for 60–90 s of muscular tension equating to between 8–12 repetitions. As an example, trainees might perform controlled 2–4 s concentric: 2–4 s eccentric phases, which should maintain muscular tension throughout the range of motion, decrease momentum and reduce high forces by preventing
3. Conclusion Authors have repeatedly reported time constraints as a barrier to RT (Trost et al., 2002; Winett et al., 2009; Van Roie et al., 2015). We believe the data provided might serve to guide medical- and exerciseprofessionals and members of the population regarding the relative simplicity of RT. As such more people might adhere to these minimal time commitments to attain the desired, and achievable, positive health adaptations discussed herein. For persons already participating in RT, it is worth guiding them to the benefits of a minimal dose approach for 82
× 3 sets Leg press, leg extension, leg curl × 3 sets Leg extension, leg curl
× 3 sets Chest press, upper back × 3 sets Pec fly, chest press, back pull-over, lateral raise, biceps curl, triceps extension, abdominal curl, low back extension, neck flexion, neck extension
Males and females with type-2 diabetes ≥ 55 years
Improved muscle quality and insulin sensitivity Improved resting blood pressure
83
Females 68–78 years
Symptomatic low back pain participants (m = 45.5 ± 14.1 years)
Males 65–75 years
Males and females 60–86 years
Improved bone mineral density
Decreased low back pain
Reduced anxiety
Improved selfesteem
(Not reported) Chest press, pec fly, pull-down, seated row, overhead press, pull-ups, bicep curl, triceps press, low back extension, abdominal curl
× 2 sets
Leg extension, leg curl
(Not reported)
Leg press, Leg curl
None
× 3 sets Low back extension × 1 set Chest press, Abdominal crunch, low back extension
× 3 sets
Leg press, leg curl, hip abductions
× 1 set Chest press, seated row, abdominal crunches, low back extension
× 1 set
Leg extension, leg flexion
× 1 set Chest press, pulldown
Males and females 56–80 years
Increased resting metabolic rate
Males and females (m = 53.8 ± 13.8 years)
× 2 sets
45–60 min
60 mina
5 min
60 mina
20 min
35 min
40 min
3
3
1–2
3
1–3
3
3
3
42 min
Leg press, leg extension, leg curl, hip abduction, hip adduction
Overhead press, upper back, chest press, pull-down, triceps, lower back, abdominal, biceps curl, sit-ups
Males 52–69 years
Decreased gastrointestinal transit time
Frequency (days/ week)
Approximate time commitment per session
Lower body volume (exercises × no. of sets)
Upper body volume (exercises × no. of sets)
Participant group (m/f, age, condition)
Health benefit
Table 1 Summary of health benefits and training intervention details.
75–85% or 55–65% 1RM
50% or 80% 1RM
80% 1RM
50–80% 1RM
8-12RM
60–80% 1RM
80% 1RM
90% of 3RM then reduced to allow 15 total repetitions
Load
Not reported
Not reported
2 s: 4 s
Not reported
2 s: 4 s
Not reported
Not reported
Supervision by partnered participant
1: 1
1: 1
2: 6
Not reported
1:1
3: 7
1 s: 2 s
4–6 s: 4–6 s
Supervision (trainer: participant)
Repetition duration (time, seconds; concentric: eccentric)
12
(Burton et al., 2016)
(Singh et al., 1997)
(Bruce-Low et al., 2012)
(Huovinen et al., 2016)
(Westcott et al., 2009)
(Brooks et al., 2007)
(Campbell et al., 1994)
(Koffler et al., 1992)
Reference
(continued on next page)
24 weeks
10
16
10
16
12
13
Duration (weeks)
J.P. Fisher et al.
Experimental Gerontology 99 (2017) 80–86
Community dwelling females 70–80 years
Community dwelling males and females ≥ 65 years
Community dwelling males and females ≥ 60 years
Improved cognitive function
Reduced fear of falling
Improved sleep quality in depressed older adults
This included a cardiovascular warm-up and cool down using aerobic equipment.
Males and females 60–84 years
Reduced depression
a
Participant group (m/f, age, condition)
Health benefit
Table 1 (continued)
× 3 sets Leg press, leg extension, leg curl × 3 sets
× 3 sets
Leg press, leg curl, leg extension
× 2 sets
× 3 sets Leg press, leg curl, calf raises
Leg press, leg extension, leg curl
Lower body volume (exercises × no. of sets)
Chest press, upright row, overhead press
× 3 sets
× 2 sets Seated row
× 3 sets Biceps curl, triceps extension, seated row, pull-down
× 2 sets Chest press, pulldown
Upper body volume (exercises × no. of sets)
45–60 min
60 mina
60 mina
45 min
Approximate time commitment per session
3
2
2
3
Frequency (days/ week)
20% or 80% 1RM
10RM
6–8 repetitions
80% 1RM
Load
Not reported
Not reported
Not reported
Not reported
Repetition duration (time, seconds; concentric: eccentric)
Supervised, but ratio not reported
Not reported
Reported as a class without ratio
1: 8
Supervision (trainer: participant)
8
50
26
10
Duration (weeks)
(Cassilhas et al., 2007)
(Singh et al., 2005)
(Yamada et al., 2011)
(Tsutsumi et al., 1998)
Reference
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Table 2 List of minimal dose/core and supplementary exercises as well as supporting academic references. Proposed importance
Exercise
References supporting the use of specific exercise for health and strength benefits
Minimal dose/core
Chest press
Minimal dose/core Minimal dose/core
Seated row Leg press
Supplementary Supplementary Supplementary
Overhead press Pull-down Leg extension
Supplementary
Leg curl
Supplementary Supplementary Supplementary
Low back extension Abdominal flexion Neck extension
(Koffler et al., 1992; Campbell et al., 1994; Huovinen et al., 2016; Westcott et al., 2009; Brooks et al., 2007; Radaelli et al., 2014; Silva et al., 2014; Schnyder and Handschin, 2015) (Koffler et al., 1992; Huovinen et al., 2016; Brooks et al., 2007; Radaelli et al., 2014; Silva et al., 2014; Van Roie et al., 2015) (Koffler et al., 1992; Huovinen et al., 2016; Brooks et al., 2007; Radaelli et al., 2014; Silva et al., 2014; Schnyder and Handschin, 2015; Van Roie et al., 2015) (Koffler et al., 1992; Radaelli et al., 2014; Schnyder and Handschin, 2015) (Koffler et al., 1992; Campbell et al., 1994; Radaelli et al., 2014) (Koffler et al., 1992; Campbell et al., 1994; Huovinen et al., 2016; Westcott et al., 2009; Brooks et al., 2007; Silva et al., 2014; Schnyder and Handschin, 2015; Van Roie et al., 2015) (Koffler et al., 1992; Campbell et al., 1994; Huovinen et al., 2016; Westcott et al., 2009; Brooks et al., 2007; Silva et al., 2014; Schnyder and Handschin, 2015; Van Roie et al., 2015) (Koffler et al., 1992; Bruce-Low et al., 2012; Huovinen et al., 2016; Westcott et al., 2009; Silva et al., 2014) (Koffler et al., 1992; Huovinen et al., 2016; Westcott et al., 2009; Silva et al., 2014) (Westcott et al., 2009; Van Roie et al., 2015)
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explosive movements. This repetition duration is supported by empirical research in older adults aged 59–79 years. For example, Watanabe et al. (2013) reported favourable increases in muscle strength and thigh muscle thickness as a result of slow-movement (3 s concentric: 1 s isometric: 3 s eccentric) compared to traditional shorter repetition durations (1 s concentric: 1 s eccentric). We encourage that persons should breathe rhythmically and avoid Valsalva manoeuvres (which results in increased intrathoracic pressure, decreased venous return and increased peripheral venous pressures during the strain phase, as well as increased stroke volume and arterial pressure following the elevated venous return immediately after the Valsalva manoeuvre (Porth et al., 1984)) whilst attempting to exercise to momentary failure (e.g. when trainees reach the point where despite attempting to do so they cannot complete the concentric portion of their current repetition without deviation from the prescribed form of the exercise). At the minimum of 3 exercises (chest press, leg press, and seated row), if a person were to move with a reasonably brief rest interval between exercises (e.g. ≤ 60 s), then each workout would take < 10 min. At the maximum of 10 exercises, or if performing multiple sets; each workout should take < 30 min. If performed 2 days/ week (ideally with 48–72 h between workouts); this would equate to a total time expense of between 20 and 60 min per week. Supervision by a qualified exercise professional might also encourage the load used to be increased in accordance with increasing participant strength, however, beginning with a minimal dose might also allow subsequent increases of any number of variables, e.g. frequency, and volume (number of sets and/or number of exercises), if necessary. It is the opinion of the authors that this example workout would suffice to attain the considerable physiological and psychological benefits discussed herein. Acknowledgements No sources of funding were used to assist in the preparation of this article. James P. Fisher, James Steele, Paulo Gentil, Jürgen Giessing, and Wayne L. Westcott declare that they have no conflicts of interest relevant to the content of this article. References Abrahin, O., Rodrigues, R.P., Nascimento, V.C., et al., 2014. Single- and multiple-set resistance training improves skeletal and respiratory muscle strength in elderly women. Clin. Interv. Aging 9, 1775–1782. Arikawa, A.Y., O'Dougherty, M., Schmitz, K., 2011. Adherence to a strength training intervention in adult women. J. Phys. Act. Health 8 (1), 111–118. Brooks, N., Layne, J.E., Gordon, P.L., et al., 2007. Strength training improves muscle quality and insulin sensitivity in Hispanic older adults with type 2 diabetes. Int. J. Med. Sci. 4 (1), 19–27. Bruce-Low, S., Smith, D., Burnet, S., et al., 2012. One lumbar extension training session per week is sufficient for strength gains and reductions in pain in patients with chronic low back pain ergonomics. Ergonomics 55 (4), 500–507.
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persons living in the community. N. Engl. J. Med. 319 (26), 1701–1707. Trost, S.G., Owen, N., Bauman, A.E., et al., 2002. Correlates of adults' participation in physical activity: review and update. Med. Sci. Sports Exerc. 34 (12), 1996–2001. Tsutsumi, T., Don, B.M., Zaichkowsky, L.D., et al., 1998. Comparison of high and moderate intensity of strength training on mood and anxiety in older adults. Percept. Mot. Skills 87 (1), 1003–1011. Van Roie, E., Bautmans, I., Coudyzer, W., Boen, F., Delecluse, C., 2015. Low- and highresistance exercise: long-term adherence and motivation among older adults. Gerontology 61 (6), 551–560. Walker, S., Serrano, J., Van Roie, E., 2017. Maximum dynamic lower-limb strength was maintained during 24 weeks reduced training frequency in previously sedentary older women. J. Strength Cond. Res. http://dx.doi.org/10.1519/JSC. 0000000000001930. (E-pub ahead of print). Watanabe, Y., Tanimoto, M., Ohgane, A., et al., 2013. Increased muscle size and strength from slow-movement, low intensity resistance exercise and tonic force generation. J. Aging Phys. Act. 21 (1), 71–84. Westcott, W.L., Winett, R.A., Annesi, J.J., et al., 2009. Prescribing physical activity: applying the ACSM protocols for exercise type, intensity, and duration across 3 training frequencies. Phys. Sportsmed. 2 (37), 51–58. Winett, R.A., Williams, D.M., Davy, B.M., 2009. Initiating and maintaining resistance training in older adults: a social cognitive theory-based approach. Br. J. Sports Med. 43 (2), 114–119. Yamada, M., Arai, H., Uemura, K., et al., 2011. Effect of resistance training on physical performance and fear of falling in elderly with different levels of physical well-being. Age Ageing 40 (5), 637–641. Yarasheski, K.E., Zachwieja, J.J., Bier, D.M., 1993. Acute effects of resistance exercise on muscle protein synthesis rate in young and elderly men and women. Am. J. Phys. 265 (2 Pt 1), E210–4.
volume strength training on neuromuscular adaptations and muscle quality in older women. Age (Dordr.) 36 (2), 881–892. Ratamess, N.A., Alvar, B.A., Evotoch, T.K., et al., 2009. American College of Sports Medicine position stand. Progression models in resistance training for healthy adults. Med. Sci. Sports Exerc. 41, 687–708. Ruiz, J.R., Sui, X., Lobelo, F., et al., 2008. Association between muscular strength and mortality in men: prospective cohort study. Br. Med. J. 337, a439. Schnyder, S., Handschin, C., 2015. Skeletal muscle as an endocrine organ: PGC-1α, myokines and exercise. Bone 80, 115–125. Schoenfeld, B.J., Ogborn, D., Krieger, J.W., 2016. Dose-response relationship between weekly resistance training volume and increases in muscle mass: a systematic review and meta-analysis. J. Sports Sci. 35 (11), 1073–1082. Silva, N.L., Oliveira, R.B., Fleck, S.J., Leon, A.C.M.P., Farinatti, P., 2014. Influence of strength training variables on strength gains in adults over 55 years-old: a metaanalysis of dose-response relationships. J. Sci. Med. Sport 17, 337–344. Singh, N.A., Clements, K.M., Fiatarone, M.A., 1997. A randomized controlled trial of progressive resistance training in depressed elders. J. Gerontol. A Biol. Sci. Med. Sci. 52 (1), M27–35. Singh, N.A., Stavrinos, T.M., Scarbek, Y., Galambos, G., Liber, C., Fiatarone-Singh, M.A., 2005. A randomized controlled trial of high versus low intensity weight training versus general practitioner care for clinical depression in older adults. J. Gerontol. A Biol. Sci. Med. Sci. 60 (6), 768–776. Srikanthan, P., Karlamangla, A.S., 2014. Muscle mass index as a predictor of longevity in older adults. Am. J. Med. 127 (6), 547–553. Steele, J., Raubold, K., Kemmler, W., Fisher, J., Gentil, P., Giessing, J., 2017. The effects of 6 months of progressive high effort resistance training methods upon strength, body composition, function, and wellbeing of elderly adults. Biomed. Res. Int., 2541090. Tinetti, M.E., Speechley, M., Ginter, S.F., 1988. Risk factors for falls among elderly
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Contents lists available at ScienceDirect
Experimental Gerontology journal homepage: www.elsevier.com/locate/expgero
Mini review
A minimal dose approach to resistance training for the older adult; the prophylactic for aging
MARK
James P. Fishera,⁎, James Steelea, Paulo Gentilb, Jürgen Giessingc, Wayne L. Westcottd a
Southampton Solent University, East Park Terrace, Southampton, UK Faculdade de Educação Física e Dança, Universidade Federal de Goias, Goiânia, Brazil c InstitutfürSportwissenschaft, Universität Koblenz-Landau, Germany d Quincy College, Quincy, MA, USA b
A R T I C L E I N F O
A B S T R A C T
Editor: Christiaan Leeuwenburgh
A plethora of research has supported the numerous health benefits of resistance training as we age, including positive relationships between muscular strength, muscle mass and reduced all-cause mortality. As such, resistance training has been referred to as medicine. However, participation and adherence remains low, with time constraints and perceived difficulty often cited as barriers to resistance training. With this in mind, we aimed to summarise the benefits which might be obtained as a product of a minimal dose approach. In this sense, participation in resistance training might serve as a prophylactic to delay or prevent the onset of biological aging. A short review of studies reporting considerable health benefits resulting from low volume resistance training participation is presented, specifically considering the training time, frequency, intensity of effort, and exercises performed. Research supports the considerable physiological and psychological health benefits from resistance training and suggests that these can be obtained using a minimal dose approach (e.g. ≤60 min, 2 d-wk− 1), using uncomplicated equipment/methods (e.g. weight stack machines). Our hope is that discussion of these specific recommendations, and provision of an example minimal dose workout, will promote resistance training participation by persons who might otherwise have not engaged. We also encourage medical professionals to use this information to prescribe resistance exercise like a drug whilst having an awareness of the health benefits and uncomplicated methods.
Keywords: Strength Health Longevity Quality of life Behaviour Adherence
1. Introduction There is an abundance of evidence highlighting the physiological benefits of resistance training (RT); including decreased gastrointestinal transit time (reducing the risk of colon cancer (Koffler et al., 1992)), increased metabolic rate (Campbell et al., 1994), reduction in low back pain (Bruce-Low et al., 2012), increased bone mineral density (Huovinen et al., 2016), reduced blood pressure (Westcott et al., 2009), and improved muscle quality and insulin sensitivity in persons with type-2 diabetes (Brooks et al., 2007). More so than these specific health benefits, evidence has supported that muscular strength (Newman et al., 2006; Ruiz et al., 2008) and muscle mass (Srikanthan and Karlamangla, 2014) are predictors of longevity and reduction in allcause mortality. Whilst increased strength and muscle mass are often goals of RT, and justifiably so due to the health benefits of these adaptations, it was recently noted that a primary objective of persons undertaking RT is “to have a biological age equal to, or lower than, our
chronological age” (Fisher et al., 2014a). This is evidently a realistic objective based on the following studies. Melov et al. (2007) reported that following 6 months of RT participants with an average age of 68 years showed mitochondrial characteristics similar to persons with a mean age of 24 years. Candow et al. (2011) reported that 22 weeks of RT eliminated the strength and muscle mass deficit of older men when compared to 18–31-year-old men. And Yarasheski et al. (1993) reported that basal fractional rate of muscle protein synthesis, whilst lower in the elderly compared to young men and women; increased to a comparable rate following only 2 weeks of RT. Combined, these health benefits are not only important for all members of the population for healthy aging, but might play a particularly crucial role in older adults given the associated sarcopenia and dynapenia, as well as risk of falls and fractures (Tinetti et al., 1988).
⁎
Corresponding author. E-mail addresses: james.fi[email protected] (J.P. Fisher), [email protected] (J. Steele), [email protected] (P. Gentil), [email protected] (J. Giessing), [email protected] (W.L. Westcott). http://dx.doi.org/10.1016/j.exger.2017.09.012 Received 29 June 2017; Received in revised form 24 August 2017; Accepted 13 September 2017 Available online 28 September 2017 0531-5565/ © 2017 Elsevier Inc. All rights reserved.
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2. Methods
(mean = 55 ± 10 years) and females (mean = 55 ± 11 years) as a result of performing 2 weekly workouts with an average of only 5 multijoint exercises per workout. Mean strength increases by exercise were: pull-down = 68 and 91%; chest press = 55 and 59%; seated row = 65 and 81%; overhead press = 39 and 58%; and leg press = 38 and 59%, for males and females, respectively. Each exercise was performed on a standard weight-stack resistance machine for only a single set each (equating to approximately 12 min per workout). Westcott et al. (2009) reported data from 1619 males and females aged between 21 and 80 years who performed 10 weeks of combined aerobic and resistance training 1 (n = 81), 2 (n = 845) or 3 (n = 693) days/week. Each exercise session was completed within 1 h, with only 20 min of RT; a single set of 10 standard weight-stack resistance machines performed to volitional fatigue for between 8 and 12 repetitions. All groups showed significant improvements in systolic and diastolic blood pressure with progressive improvements in body fat reduction and muscle mass increase aligned with greater training frequency.1 The authors also reported a drop-out rate of only 9%, and adherence of 84%, 83% and 80% for the 1, 2 and 3 days/week groups, respectively. Most recently Steele et al. (2017) reported significant increases in strength and functional tasks (e.g. a stair climb task, carrying of shopping basket task, and chair rise task) and wellbeing following 6 months of high effort, twice weekly resistance training using a single set of leg press, chest press, seated row, knee extension, knee flexion, trunk extension and trunk flexion exercises. However, despite these very positive findings we should consider that some studies have produced equivocal data. For example, Walker et al. (2017) considered strength, muscle activation and muscle mass for the quadriceps of older adults (64–75 years) performing reduced RT. Following 12 weeks of 2 days/week RT, participants were divided in to those continuing at the same frequency and those reducing training to only 1 day/week, for a further 24 weeks. Both strength and muscle activation continued to increase in both groups with no significant between-group differences. However, the authors reported reductions in CSA for the reduced frequency group. It might be that muscle function can be sustained with low frequency training whereas muscle mass requires RT of 2 days/week to be maintained.
Position stands by the likes of the American College of Sports Medicine (ACSM) might be interpreted to support the necessity for complicated, high-volume RT programmes (Ratamess et al., 2009), which might serve to deter engagement and adherence. Indeed, time constraints and perceived difficulty are often cited as barriers to RT (Trost et al., 2002; Winett et al., 2009). As such, we aimed to assess what benefits might be attained from, and what might constitute, a minimal dose approach to RT. For this commentary, we considered some of the seminal literature considering a variety of positive physiological and psychological health adaptations resulting from RT, including those where details of volume and frequency were included/ could be calculated. It is worth noting that this is not an exhaustive review and word constraints prevent greater analysis. However, this article is intended to determine the approximate minimal necessary volume and frequency to identify a ‘minimal dose’ of RT for the evidenced health benefits. 2.1. Dosage Whilst emphasis has been placed on the considerable health benefits of RT, many people might not realise that these positive responses have been attained using a low to moderate dose of RT. For example, in the above studies participants performed RT for low- (~ 20 min, to ~ 35 min (Brooks et al., 2007)) to moderate- (~ 40 min (Campbell et al., 1994) and ~60 min (Huovinen et al., 2016)) volumes, 3 days/week. Notably, time might be saved by performing only multi-joint exercises, as opposed to the addition of single joint exercises. For example, Gentil et al. (2016) suggested that use of only multi-joint exercises appears to produce similar increases in strength and muscle mass as higher volumes of training through the addition of single-joint exercises. Furthermore, whilst some authors have reported more favourable increases in strength and hypertrophy by performing multiple sets of an exercise (Krieger, 2009; Krieger, 2010; Schoenfeld et al., 2016), in older adults, there seems to be no consistent benefit beyond single-set RT. For example, Cannon and Marino (2010) reported that younger and older women showed similar increases in knee extension muscle strength and size when performing RT with one or three sets per exercise after 10 weeks, with no significant interactions between age or number of sets and time. Abrahin et al. (2014) found similar gains in functional tests, as well as strength and muscular endurance of older women after performing 24 sessions with either one or three sets per exercise. Galvão and Taaffe (2005) compared the effects of 20 weeks of one vs. three sets per exercise and found inconsistent results. The high-volume group showed greater increases in maximal strength for seated row, triceps extension, and leg extension as well as muscular endurance in the chest press and leg press. However, there were no between-group differences in biceps curl, chest press, leg press and leg curl maximum strength as well as in isometric and isokinetic knee extensor peak torque. Furthermore, improvement in functional tests and body composition also did not differ between groups. More recently, Radaelli et al. (2014) compared the effects of 20 weeks of one vs. three sets of resistance exercise in older women and reported favourable increases for the multiple set group for knee extension 1-repetition maximum (1RM), but no between-group differences for increases in elbow flexion 1RM. In fact, a meta-analysis by Silva et al. (2014) suggested that variance in load (55–84% 1RM), volume (1–6 sets), or frequency (1–3 days/week) did not produce significantly different strength increases in adults over 55 years. In further support of the proposed low-volume approach for strength increases; Koffler et al. (1992) used a single set for upper body exercises and 2 sets for lower body exercises reporting strength increases of (mean ± standard deviation) 41 ± 5% (p < 0.001) and 45 ± 6% (p < 0.001), respectively. Fisher et al. (2014b) reported significant (p < 0.001 to p = 0.014) strength increases in older males
2.2. Additional health benefits Further benefits to RT have been identified including myokine release; hormones released by skeletal muscle tissue which serve to combat metabolic disorders (Schnyder and Handschin, 2015), improved cognitive functioning (Nagamatsu et al., 2012), and an array of psychological health benefits including; a reduction of fear of falling in the frail elderly (Yamada et al., 2011), improved sleep quality in depressed older adults (Singh et al., 2005), reduced anxiety (Cassilhas et al., 2007), reduced depression (Singh et al., 1997) and improved selfesteem (Tsutsumi et al., 1998). Whilst some of these RT doses were also low- (≤ 60 min, 2 days/week (Nagamatsu et al., 2012; Yamada et al., 2011; Singh et al., 2005)) and moderate- (45–60 min, 3 days/week (Cassilhas et al., 2007; Singh et al., 1997; Tsutsumi et al., 1998)) in volume, other studies failed to provide sufficient details to determine a training time. Research has supported that the main motivator for older adults to participate in RT would be “…to feel good mentally and physically…” (Burton et al., 2016). Combined the psycho-social benefits and physiological adaptations outlined would serve to improve quality of life and encourage older adults to be more interactive and engaged in daily activities and socialisation.
1 It is worth acknowledging that an aerobic exercise component during the 1-hour session might have expedited positive blood pressure and body composition adaptations.
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differing reasons. Whilst it is difficult to individually determine at what point RT becomes excessive (i.e. an ‘overdose’) and thus; might incur negative side-effects, there is certainly evidence to suggest that too much exercise can result in overreaching (a short-term state preceding overtraining). Overreaching might result in a decreased immune system (often resulting in upper respiratory tract infections), a decrease in the testosterone: cortisol ratio (which might be indicative of imbalance in anabolic and catabolic physiological states) and psychological disturbances and negative affective states (Halson and Jeukendrup, 2004; Hooper et al., 1997). Whilst overreaching might be relatively common in athletic populations, and recovery appears reasonably brief (e.g. within 2 weeks), we suggest that this is something to be avoided in the lay population or older adults. Since these symptoms might also parallel short-term strength decreases, we feel it is important to draw attention to this since a common response to a decrement in strength is to do more training in an attempt to overcome this, rather than rest and recover. With this in mind, we propose that, in order to avoid excess, and as with medication, participants approach RT using a minimum dose that might later be adapted if necessary. We have presented evidence that uncomplicated resistance exercise (e.g. 3–10 weight-stack machines performed for a single set) at a low to moderate dosage (< 60 min, 2 days / week) might be all that is necessary to attain the aforementioned positive health adaptations. We recommend that this dose is within the capacity of all or most members of the population, particularly older adults who might benefit more from the physiological and psychological benefits. We hope this article provides the motivation to those who most need RT by improving their understanding of the dose demands, as well as serving to promote both the simplicity and potential health benefits of RT to medical professionals so that they might be confident to prescribe exercise like a drug. Furthermore, researchers might consider the efficacy of a low-volume, minimal dose approach in their RT studies to consider the efficacy in relation to additional positive adaptations.
2.3. Intensity of effort, adherence and supervision Perhaps the only caveat to such a minimal dose approach is the apparent need for participants to exercise to a high intensity of effort. In the studies detailed, the exercise protocols achieved more favourable adaptations where participants were required to lift a moderate to heavy load (e.g. 50–90% 1-repetition maximum; RM) and either exercise to momentary failure (e.g. where they could not complete another repetition despite attempting to do so) or complete multiple sets of each exercise permitting cumulative fatigue and higher effort in later sets. In some cases, favourable trainer:client supervision ratios supported the high intensity of effort, e.g. 1:1 (Fisher et al., 2014b; Steele et al., 2017) or 2:6 (Westcott et al., 2009). Certainly, evidence has previously supported greater increases in upper and lower body strength in a high supervision (1:5; trainer to athlete ratio) compared to a low supervision (1:25) group (Gentil and Bottaro, 2010). Indeed, the aforementioned study by Steele et al. (2017) permitted participants to continue unsupervised RT for a further 6 months after their initial 6 month supervised intervention. Data revealed that when unsupervised, RT produced similar strength and functional task outcomes to those who discontinued training entirely. Furthermore, supervision appears to improve adherence. For example, Arikawa et al. (2011) reported adherence rates of 95.4% and 64.5% during supervised and unsupervised periods of a RT intervention in overweight women. This is supported by Van Roie et al. (2015), who reported diminished adherence when participants were permitted to continue exercising following the end of a supervised intervention. In fact, only 11–21% of participants continued RT, with those discontinuing citing perceived lack of time as the most common reason (46%). As such, whilst the aforementioned study by Westcott et al. (2009) showed high adherence/low drop-out rates, this might be, at least partially, a product of participants attending supervised exercise sessions. In summary, whilst motivated persons might attain the necessary effort levels without such supervision, the previous studies by Steele et al. (2017), Arikawa et al. (2011) and Van Roie et al. (2015) suggest that supervision might be important for adherence and outcomes. The health benefits reported as a result of RT, along with the specific variables of the research interventions (e.g. exercises performed, volume, approximate time commitment, frequency, supervision ratio, and duration) are reported in Table 1. It is also worth clarifying that participants within the majority of studies exercised predominantly using standard weight-stack resistance machines. This serves to both save time by simply adjusting the load via the use of a pin rather than loading and unloading weight plates, and simplifies the training session potentially making it more appealing to persons less confident or inexperienced in a gym environment. Furthermore, data suggests that machine-based resistance might be safer than free-weight exercises (Kerr et al., 2010). We also suggest that bodyweight alternatives might exist should persons not have access to the resistance machines detailed. Certainly, evidence supports that muscular tension might be all that is necessary to increase muscle strength and size, even using simple isometric cocontraction (Maeo et al., 2013). However, because of the technical elements of bodyweight exercise we advocate supervision to retain good posture and avoid injury.
4. Practical application In the interests of clarity, a ‘minimal dose’ example workout would be to perform multi-joint exercises for the major muscle groups, e.g. chest press, leg press, and seated row. Supplementary, but non-essential exercises include the overhead press and pull-down exercises, where contraindications such as high blood pressure or limited shoulder mobility/impingement do not exist. Lower body single joint exercises should be included (e.g. leg curl and knee extension) if the leg press is unsuitable for any reason or as additional lower body exercises should there be a need to specifically target the knee extensors/flexors. Inclusion of lumbar extension, and abdominal flexion exercises should be included intermittently to reduce risk or severity of back pain (Bruce-Low et al., 2012), improve posture, and protect the spine and vital organs. Finally, evidence has shown that the cervical extensors are especially weak and as such including a neck extension exercise will serve to strengthen these muscles which, evidence suggests, plays a role in reduced injury risk (Fisher et al., 2016; Hislop et al., 2017). Academic support for the inclusion of each specific exercise is provided in Table 2. This selection of exercises serves to target the major muscle masses of the body and promote positive health adaptations. This workout might ideally be performed under direct supervision of a fitness professional to assess client suitability of these exercises, coach correct technique and provide encouragement which might serve to increase participant intensity of effort. However, without supervision this workout is still suitable for an inexperienced person, and might require only a single set of each exercise, performed for 60–90 s of muscular tension equating to between 8–12 repetitions. As an example, trainees might perform controlled 2–4 s concentric: 2–4 s eccentric phases, which should maintain muscular tension throughout the range of motion, decrease momentum and reduce high forces by preventing
3. Conclusion Authors have repeatedly reported time constraints as a barrier to RT (Trost et al., 2002; Winett et al., 2009; Van Roie et al., 2015). We believe the data provided might serve to guide medical- and exerciseprofessionals and members of the population regarding the relative simplicity of RT. As such more people might adhere to these minimal time commitments to attain the desired, and achievable, positive health adaptations discussed herein. For persons already participating in RT, it is worth guiding them to the benefits of a minimal dose approach for 82
× 3 sets Leg press, leg extension, leg curl × 3 sets Leg extension, leg curl
× 3 sets Chest press, upper back × 3 sets Pec fly, chest press, back pull-over, lateral raise, biceps curl, triceps extension, abdominal curl, low back extension, neck flexion, neck extension
Males and females with type-2 diabetes ≥ 55 years
Improved muscle quality and insulin sensitivity Improved resting blood pressure
83
Females 68–78 years
Symptomatic low back pain participants (m = 45.5 ± 14.1 years)
Males 65–75 years
Males and females 60–86 years
Improved bone mineral density
Decreased low back pain
Reduced anxiety
Improved selfesteem
(Not reported) Chest press, pec fly, pull-down, seated row, overhead press, pull-ups, bicep curl, triceps press, low back extension, abdominal curl
× 2 sets
Leg extension, leg curl
(Not reported)
Leg press, Leg curl
None
× 3 sets Low back extension × 1 set Chest press, Abdominal crunch, low back extension
× 3 sets
Leg press, leg curl, hip abductions
× 1 set Chest press, seated row, abdominal crunches, low back extension
× 1 set
Leg extension, leg flexion
× 1 set Chest press, pulldown
Males and females 56–80 years
Increased resting metabolic rate
Males and females (m = 53.8 ± 13.8 years)
× 2 sets
45–60 min
60 mina
5 min
60 mina
20 min
35 min
40 min
3
3
1–2
3
1–3
3
3
3
42 min
Leg press, leg extension, leg curl, hip abduction, hip adduction
Overhead press, upper back, chest press, pull-down, triceps, lower back, abdominal, biceps curl, sit-ups
Males 52–69 years
Decreased gastrointestinal transit time
Frequency (days/ week)
Approximate time commitment per session
Lower body volume (exercises × no. of sets)
Upper body volume (exercises × no. of sets)
Participant group (m/f, age, condition)
Health benefit
Table 1 Summary of health benefits and training intervention details.
75–85% or 55–65% 1RM
50% or 80% 1RM
80% 1RM
50–80% 1RM
8-12RM
60–80% 1RM
80% 1RM
90% of 3RM then reduced to allow 15 total repetitions
Load
Not reported
Not reported
2 s: 4 s
Not reported
2 s: 4 s
Not reported
Not reported
Supervision by partnered participant
1: 1
1: 1
2: 6
Not reported
1:1
3: 7
1 s: 2 s
4–6 s: 4–6 s
Supervision (trainer: participant)
Repetition duration (time, seconds; concentric: eccentric)
12
(Burton et al., 2016)
(Singh et al., 1997)
(Bruce-Low et al., 2012)
(Huovinen et al., 2016)
(Westcott et al., 2009)
(Brooks et al., 2007)
(Campbell et al., 1994)
(Koffler et al., 1992)
Reference
(continued on next page)
24 weeks
10
16
10
16
12
13
Duration (weeks)
J.P. Fisher et al.
Experimental Gerontology 99 (2017) 80–86
Community dwelling females 70–80 years
Community dwelling males and females ≥ 65 years
Community dwelling males and females ≥ 60 years
Improved cognitive function
Reduced fear of falling
Improved sleep quality in depressed older adults
This included a cardiovascular warm-up and cool down using aerobic equipment.
Males and females 60–84 years
Reduced depression
a
Participant group (m/f, age, condition)
Health benefit
Table 1 (continued)
× 3 sets Leg press, leg extension, leg curl × 3 sets
× 3 sets
Leg press, leg curl, leg extension
× 2 sets
× 3 sets Leg press, leg curl, calf raises
Leg press, leg extension, leg curl
Lower body volume (exercises × no. of sets)
Chest press, upright row, overhead press
× 3 sets
× 2 sets Seated row
× 3 sets Biceps curl, triceps extension, seated row, pull-down
× 2 sets Chest press, pulldown
Upper body volume (exercises × no. of sets)
45–60 min
60 mina
60 mina
45 min
Approximate time commitment per session
3
2
2
3
Frequency (days/ week)
20% or 80% 1RM
10RM
6–8 repetitions
80% 1RM
Load
Not reported
Not reported
Not reported
Not reported
Repetition duration (time, seconds; concentric: eccentric)
Supervised, but ratio not reported
Not reported
Reported as a class without ratio
1: 8
Supervision (trainer: participant)
8
50
26
10
Duration (weeks)
(Cassilhas et al., 2007)
(Singh et al., 2005)
(Yamada et al., 2011)
(Tsutsumi et al., 1998)
Reference
J.P. Fisher et al.
Experimental Gerontology 99 (2017) 80–86
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Table 2 List of minimal dose/core and supplementary exercises as well as supporting academic references. Proposed importance
Exercise
References supporting the use of specific exercise for health and strength benefits
Minimal dose/core
Chest press
Minimal dose/core Minimal dose/core
Seated row Leg press
Supplementary Supplementary Supplementary
Overhead press Pull-down Leg extension
Supplementary
Leg curl
Supplementary Supplementary Supplementary
Low back extension Abdominal flexion Neck extension
(Koffler et al., 1992; Campbell et al., 1994; Huovinen et al., 2016; Westcott et al., 2009; Brooks et al., 2007; Radaelli et al., 2014; Silva et al., 2014; Schnyder and Handschin, 2015) (Koffler et al., 1992; Huovinen et al., 2016; Brooks et al., 2007; Radaelli et al., 2014; Silva et al., 2014; Van Roie et al., 2015) (Koffler et al., 1992; Huovinen et al., 2016; Brooks et al., 2007; Radaelli et al., 2014; Silva et al., 2014; Schnyder and Handschin, 2015; Van Roie et al., 2015) (Koffler et al., 1992; Radaelli et al., 2014; Schnyder and Handschin, 2015) (Koffler et al., 1992; Campbell et al., 1994; Radaelli et al., 2014) (Koffler et al., 1992; Campbell et al., 1994; Huovinen et al., 2016; Westcott et al., 2009; Brooks et al., 2007; Silva et al., 2014; Schnyder and Handschin, 2015; Van Roie et al., 2015) (Koffler et al., 1992; Campbell et al., 1994; Huovinen et al., 2016; Westcott et al., 2009; Brooks et al., 2007; Silva et al., 2014; Schnyder and Handschin, 2015; Van Roie et al., 2015) (Koffler et al., 1992; Bruce-Low et al., 2012; Huovinen et al., 2016; Westcott et al., 2009; Silva et al., 2014) (Koffler et al., 1992; Huovinen et al., 2016; Westcott et al., 2009; Silva et al., 2014) (Westcott et al., 2009; Van Roie et al., 2015)
Burton, E., Lewin, G., Pettigrew, S., et al., 2016. Identifying motivators and barriers to older community-dwelling people participating in resistance training: a cross-sectional study. J. Sports Sci (E-Pub ahead of print). Campbell, W.W., Crim, M.C., Young, V.R., et al., 1994. Increased energy requirements and changes in body composition with resistance training in older adults. Am. J. Clin. Nutr. 60, 167–175. Candow, D.G., Chilibeck, P.D., Abeysekara, S., et al., 2011. Short-term heavy resistance training eliminates age-related deficits in muscle mass and strength in healthy older males. J. Strength Cond. Res. 25 (2), 326–333. Cannon, J., Marino, F.E., 2010. Early-phase neuromuscular adaptations to high- and lowvolume resistance training in untrained young and older women. J. Sports Sci. 28 (14), 1505–1514. Cassilhas, R.C., Viana, V.A.R., Grassman, V., et al., 2007. The impact of resistance exercise on the cognitive function of the elderly. Med. Sci. Sports Exerc. 39, 1401–1407. Fisher, J., Steele, J., Brzycki, M., et al., 2014a. Primum non nocere: a commentary on avoidable injuries and safe resistance training techniques. J. Trainol. 3, 31–34. Fisher, J., Steele, J., McKinnon, P., McKinnon, S., 2014b. Strength gains as a result of brief, infrequent resistance exercise in older adults. J. Sports Med., 731890. Fisher, J.P., Asanovich, M., Cornwell, R., Steele, J., 2016. A neck strengthening protocol in adolescent males and females for athletic injury prevention. J. Trainol. 5, 13–17. Galvão, D.A., Taaffe, D.R., 2005. Resistance exercise dosage in older adults: single- versus multiset effects on physical performance and body composition. J. Am. Geriatr. Soc. 53 (12), 2090–2097. Gentil, P., Bottaro, M., 2010. Influence of supervision ratio on muscle adaptations to resistance training in nontrained subjects. J. Strength Cond. Res. 24 (3), 639–643. Gentil, P., Fisher, J., Steele, J., 2016. A review of the acute effects and long term adaptations of single- and multi-joint exercises during resistance training. Sports Med (EPub ahead of print). Halson, S.L., Jeukendrup, A.E., 2004. Does overtraining exist? An analysis of overreaching and overtraining research. Sports Med. 34 (14), 967–981. Hislop, M.D., Stokes, K.A., Williams, S., et al., 2017. Reducing musculoskeletal injury and concussion risk in schoolboy rugby players with a pre-activity movement control exercise programme: a cluster randomised controlled trial. Br. J. Sports Med. 51 (15), 1140–1146. Hooper, S., MacKinnon, L.T., Hanrahan, S., 1997. Mood states as an indication of staleness and recovery. Int. J. Sports Psych. 28 (1), 1–12. Huovinen, V., Ivaska, K.K., Kiviranta, R., et al., 2016. Bone mineral density is increased after a 16-week resistance training intervention in elderly women with decreased muscle strength. Eur. J. Endocrinol. 175 (6), 571–582. Kerr, Z.Y., Collins, C.L., Comstock, R.D., 2010. Epidemiology of weight training-related injuries presenting to United States emergency departments, 1990–2007. Am. J. Sports Med. 38, 765–771. Koffler, K., Menkes, A., Redmond, R.A., et al., 1992. Strength training accelerates gastrointestinal transit in middle-aged and older men. Med. Sci. Sports Exerc. 24, 415–419. Krieger, J.W., 2009. Single versus multiple sets of resistance exercise: a meta-regression. J. Strength Cond. Res. 23, 1890–1901. Krieger, J.W., 2010. Single vs. multiple sets of resistance exercise for muscle hypertrophy: a meta-analysis. J. Strength Cond. Res. 24, 1150–1159. Maeo, S., Yoshitake, Y., Takai, Y., et al., 2013. Neuromuscular adaptations following 12week maximal voluntary co-contraction training. Eur. J. Appl. Physiol. 114 (4), 663–673. Melov, S., Tamopolsky, M.A., Bechman, K., et al., 2007. Resistance exercise reverses aging in human skeletal muscle. PLoS ONE 2 (5), e465. Nagamatsu, L.S., Handy, T.C., Hsu, C.L., et al., 2012. Resistance training improves cognitive and functional brain plasticity in seniors with probable MCI: a 6-month randomized controlled trial. Arch. Intern. Med. 172 (8), 666–668. Newman, A.B., Kupelian, V., Visser, M., et al., 2006. Strength, but not muscle mass, is associated with mortality in the health, aging and body composition study cohort. J. Gerontol. A Biol. Sci. Med. Sci. 61 (1), 72–77. Porth, C.J., Bamrah, V.S., Tristani, F.E., et al., 1984. The Valsalva manoeuvre: mechanisms and clinical applications. Heart Lung 13 (5), 507–518. Radaelli, R., Botton, C.E., Wilhelm, E.N., et al., 2014. Time course of low- and high-
explosive movements. This repetition duration is supported by empirical research in older adults aged 59–79 years. For example, Watanabe et al. (2013) reported favourable increases in muscle strength and thigh muscle thickness as a result of slow-movement (3 s concentric: 1 s isometric: 3 s eccentric) compared to traditional shorter repetition durations (1 s concentric: 1 s eccentric). We encourage that persons should breathe rhythmically and avoid Valsalva manoeuvres (which results in increased intrathoracic pressure, decreased venous return and increased peripheral venous pressures during the strain phase, as well as increased stroke volume and arterial pressure following the elevated venous return immediately after the Valsalva manoeuvre (Porth et al., 1984)) whilst attempting to exercise to momentary failure (e.g. when trainees reach the point where despite attempting to do so they cannot complete the concentric portion of their current repetition without deviation from the prescribed form of the exercise). At the minimum of 3 exercises (chest press, leg press, and seated row), if a person were to move with a reasonably brief rest interval between exercises (e.g. ≤ 60 s), then each workout would take < 10 min. At the maximum of 10 exercises, or if performing multiple sets; each workout should take < 30 min. If performed 2 days/ week (ideally with 48–72 h between workouts); this would equate to a total time expense of between 20 and 60 min per week. Supervision by a qualified exercise professional might also encourage the load used to be increased in accordance with increasing participant strength, however, beginning with a minimal dose might also allow subsequent increases of any number of variables, e.g. frequency, and volume (number of sets and/or number of exercises), if necessary. It is the opinion of the authors that this example workout would suffice to attain the considerable physiological and psychological benefits discussed herein. Acknowledgements No sources of funding were used to assist in the preparation of this article. James P. Fisher, James Steele, Paulo Gentil, Jürgen Giessing, and Wayne L. Westcott declare that they have no conflicts of interest relevant to the content of this article. References Abrahin, O., Rodrigues, R.P., Nascimento, V.C., et al., 2014. Single- and multiple-set resistance training improves skeletal and respiratory muscle strength in elderly women. Clin. Interv. Aging 9, 1775–1782. Arikawa, A.Y., O'Dougherty, M., Schmitz, K., 2011. Adherence to a strength training intervention in adult women. J. Phys. Act. Health 8 (1), 111–118. Brooks, N., Layne, J.E., Gordon, P.L., et al., 2007. Strength training improves muscle quality and insulin sensitivity in Hispanic older adults with type 2 diabetes. Int. J. Med. Sci. 4 (1), 19–27. Bruce-Low, S., Smith, D., Burnet, S., et al., 2012. One lumbar extension training session per week is sufficient for strength gains and reductions in pain in patients with chronic low back pain ergonomics. Ergonomics 55 (4), 500–507.
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