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Physical fitness profile in adults with intellectual disabilities: Differences between levels of sport practice
Research in Developmental Disabilities 32 (2011) 788–794
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Research in Developmental Disabilities
Physical fitness profile in adults with intellectual disabilities: Differences between levels of sport practice Antonio Ignacio Cuesta-Vargas a,*, Berta Paz-Lourido b, Alejandro Rodriguez c a
Department of Physiotherapy, University of Malaga, Av de Martiricos s/n, 29071 Malaga, Spain Department of Nursing and Physiotherapy, University of the Balearic Islands, Beatriu de Pino´s Building, Cra. De Valldemossa, km 7.5, 07122 Palma de Mallorca, Spain c National Health Service of Castilla de la Mancha, Spain b
A R T I C L E I N F O
A B S T R A C T
Article history: Received 26 October 2010 Accepted 28 October 2010 Available online 15 December 2010
Neuromuscular and aerobic capacity can be reduced in people with intellectual disabilities (ID). Previous studies suggest these individuals might be particularly susceptible to losing basic functions because of poor physical fitness. The aim of this study is to describe the physical fitness profile of adult athletes with ID and identify whether there are differences in the physical performance between the most physically active individuals and less active individuals. A cross-sectional observational study was developed involving 266 athletes with mild ID (187 males and 79 females), recruited from the Spanish Special Olympics Games. A questionnaire was used to evaluate the health status of participants and their frequency of physical activity practice. A battery of 13 fitness tests was applied to assess flexibility, strength/endurance, balance and cardiovascular capabilities. Of the total participants, 44.3% were classified as sportspersons and the remainder as non sportspersons, taking in consideration the frequency of physical activity. Regarding the scores, a significant difference was found in degrees of flexibility between genders, higher for females for one test but higher for males in the other three. A significant difference was not encountered between other variables of physical fitness, although the men’s scores were higher in strength/endurance and balance. When the scores of the sportspersons and non sportspersons groups were compared, no significant difference was found between the two, with the exception of one test for flexibility. Differences among groups and gender were not statistically significant in most of the tests. The findings in this study illustrate an unclear and inconclusive relation between the scores and the declared level of physical activity, maybe due to the context in which participants for the study were selected. ß 2010 Elsevier Ltd. All rights reserved.
Keywords: Physical fitness Intellectual disabilities Sport Musculoskeletal development
1. Introduction The fitness of adults with intellectual disabilities (ID) has been found to be significantly weaker than in individuals without ID at all stages of life (Angelopoulou, Tsimaras, Christoulas, Kokaridas, & Mandroukas, 1999; Angelopoulou et al., 2000; Carmeli, Ayalon, Barchad, Sheklow, & Reznick, 2002; Carmeli, Barchad, Lenger, & Coleman, 2002; Carmeli, Kessel, Coleman, & Ayalon, 2002; Croce, Pitetti, Horvat, & Miller, 1996; Horvat, Pitetti, & Croce, 1997; Pitetti & Boneh, 1995; Pitetti, Climstein, Mays, & Barrett, 1992; Skowronski, Horvat, Nocera, Roswal, & Croce, 2009). Neuromuscular and aerobic capacity can be severely reduced in adults with intellectual disabilities (Fernhall & Pitetti, 2001), suggesting that these individuals
* Corresponding author. Tel.: +34 952137551; fax: +34 971172309. E-mail addresses: [email protected], [email protected] (A.I. Cuesta-Vargas), [email protected] (B. Paz-Lourido), [email protected] (A. Rodriguez). 0891-4222/$ – see front matter ß 2010 Elsevier Ltd. All rights reserved. doi:10.1016/j.ridd.2010.10.023
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might be particularly susceptible to a loss of basic functioning because of poor physical fitness (Carmeli, Barchad, et al., 2002; Pitetti & Boneh, 1995). Despite the benefits of physical activity in balance, strength, endurance and health self-perception (Carmeli, ZingerVaknin, Morad, & Merrick, 2005), physical fitness has been further related to job opportunities and vocational performance in adults with ID (Beasley, 1982; Croce & Horvat, 1992; Horvat & Croce, 1995). Other studies with adults with ID show the positive influence of employment that requires competitive and high functional work ability, illustrating the relevance of physical activity in many spheres of life for broader wellbeing (Kober & Eggleton, 2005; Stephens, Collins, & Dodder, 2005). The demonstrated link between physical fitness and time performance of functional tasks of daily living in adults with ID (Cowley et al., 2010) suggests the importance of studies on the topic. The participation of children and adults with disabilities in sports and recreational activities has often been addressed to enhance overall wellbeing and promote social inclusion (Wilson, 2002). However, some barriers to their active participation in regular exercise have been identified. The individual’s functional limitations, the high costs or the lack of nearby facilities or programmes are some of the reasons for nonparticipation (King et al., 2003). Some literature suggests that many individuals with ID have poor adherence to physical activity programs or sports (McGuire, Daly, & Smyth, 2007), what puts this group at relatively high risk for the development of multiple negative consequences of a sedentary lifestyle (Lotan, Isakov, Kessel, & Merrick, 2004). Nevertheless, data on this topic seems to be insufficient to determine whether individuals with ID are currently less active than their peers without disabilities (Frey, Stanish, & Temple, 2008; Temple, Frey, & Stanish, 2006). Among the institutions that promote wellbeing and empower people with ID through sports, the Special Olympics organisation (www.specialolympics.com) offers the largest selection of recreational activities, including national and international competitive sport games. Special Olympics also develops diverse healthcare programmes aimed to screen the health status of athletes and give them and their families support when needed. One of this is the FUNFitness programme, which provides screenings to evaluate the physical status of the participants in the games and offers them practical suggestions to improve their health condition and avoid injuries. After the screening, all athletes are provided with specific information regarding their physical profile. Health education with emphasis in musculoskeletal issues is also given, using educational materials tailored for people with lower reading levels when necessary. The impact of Special Olympics games in the participants’ health status has been studied at psychosocial and physical level. Besides the consideration of sport as a significant life experience for the special olympians (Mharada & Siperstein, 2009), they may benefit in perceived competence, self-awareness and social acceptance (Gibbons & Bushakra, 1989; Weiss, Diamond, Demark, & Lovald, 2003). However, the impact of the games in increasing the physical profile of participants seems to be low if it is not accompanied by regular training (Machek, Stopka, Tillman, Sneed, & Naugle, 2008; Pitteti, Jackson, Stubbs, Campbell, & Saraswathy, 1989). With this research we aimed to describe the physical fitness profile of adult athletes with ID and identify whether there are differences in the physical performance between the most physically active individuals (sportspeople) and the less active individuals (non sportspeople). 2. Material and methods 2.1. Participants Participants in this study were 266 individuals with ID (187 males and 79 females) recruited from the Spanish Special Olympics Games. The mean age of participants was 31.1 with a standard deviation of 7.5 years. All participants had been medically diagnosed with a mild intellectual disability. General issues regarding the health status were checked before participation in the study and data regarding their health history was obtained from the participants and their parents and/or guardians. This health history included questions regarding the level of adherence to sports or regular physical activities. The hours per week the athletes practice physical activity or sport were recorded to classify the participants regarding their activeness. The participants were identified as sportspeople when they practiced physical activities from 3 to 7 h per week, and a non sportspeople when they practiced from 1 to 2 h per week. Exclusion criteria to participate in the study included: (1) any contraindications to exercise as assessed by a medical history questionnaire, (2) documented atherosclerotic heart disease, (3) documented atlantoaxial instability, (4) uncorrected congenital heart disease, and (5) implanted pacemaker. 2.2. Study design and instruments This cross-sectional observational study employed a battery of 13 fitness tests including: the passive knee extension test, the calf muscle flexibility test, the anterior hip flexibility test, the functional shoulder rotation test, the timed-stand test, the partial sit-up test, the seated push-up, the grip test, the single leg stance open and closed eyes, and the 3 min walk test. A detailed description of the tests and data regarding reliability is given in this section. The examiners were 10 qualified physiotherapists and 15 trained physiotherapy students from the residency programmes. A four-hour training session was previously developed for the examiners to become acquainted with the specific fitness tests to be used. Other aspects regarding social interaction with individuals with ID were included in the
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training session. Due to the importance for the athletes to comprehend what was required from them during the screening, special emphasis was given to communication issues. Tests were explained to the athletes and repeated several times if necessary. Quite frequently, examiners had to demonstrate how to perform the tests to check that the participants indeed understood what was required from them. Tests were performed with at least two examiners to assure that the measure was done correctly but also to give support, to encourage and to ensure the safety of the athletes during the tests performance. Passive knee extension (PKE). The athlete was positioned supine on a treatment table with hip and knee flexed at 908. The passive knee extension was measured using a goniometer, with the fulcrum placed over the lateral femoral epicondyle and its arms in the direction of the greater trochanter and lateral malleolus, respectively. Their ankle remained in a neutral position or in plantarflexion. If the knee was fully extended, the final value was recorded as 08. If the knee didn’t extend, the value was recorded as negative (e.g., 408). If the knee went beyond the fully straight position into hyperextension, the value was recorded as positive (e.g., +58). The reliability of the PKE test was explored and compared with other clinical tests for assessing hamstring muscle as proposed by Gajdoski, Rieck, Sullivan, and Wightman (1993). Calf muscle flexibility (CMF). The athlete was positioned supine on a table, with the hip and knee on the side to be measured in as much extension as possible. The fulcrum of the goniometer was placed over the lateral malleolus, with one of its arms in the direction of the fibular head and the other one in parallel to the lateral midline of the fifth metatarsal. Their ankle was passively dorsiflexed and its angle measured while their knee remained in extension. If the athlete couldn’t reach neutral position, the angle was recorded as negative (e.g., 108). If the athlete went beyond neutral, it was recorded as positive (e.g., +108). If the athlete only reached neutral, it was recorded as 08. The reliability of this test can be found in Ekstrand, Wiktorsonn, Oberg, and Gilquist (1982). Anterior hip flexibility (AHF). The athlete was positioned supine on a table, both hips flexed to 908. The hip to be measured was flexed up to 1008 with a hand beneath the lower back to ensure that it remained flattened. Opposite hip was kept at 908 and not allowed to move into extension during the test. The fulcrum of the goniometer was placed over the greater trochanter, with its arms aligned with the lateral midline of the pelvis and with the lateral midline of the femur, respectively. The degrees of extension between the pelvis and thigh were measured before the pelvis began to move forward. If the thigh lowered to the table surface, the result was recorded as 08. If the thigh didn’t reach the table, the angle was recorded as negative (e.g., 258). The reliability of this test can be found in Ekstrand et al. (1982). Functional shoulder rotation (FSR). The athlete stood or was seated facing the back of a chair. The athlete was instructed to reach one arm behind the head and down the back, while the other arm reached behind the hip and up the back. The athlete was instructed to ‘‘try to touch their index fingers together.’’ A tape measure was used to measure the distance in cm between the index fingers in this position (one arm was in flexion/abduction/lateral rotation; the other was in extension/ adduction/medial rotation). The arm on top defined the recorded side (i.e., left arm on top = left; right arm on top = right). If the fingertips touched, the distance was recorded as 0. If the fingertips could not touch, the separation was recorded as negative (e.g., 15.2 cm). If the fingers overlap, the overlap was recorded as positive (e.g., +2.5 cm). The FSR is a reproducible measure of upper extremity function task that was validated in people with disabilities. The reliability of this test can be found in Bostro¨m, Harms-Ringdahl, and Nordemar (1991). The timed-stands test (TST). The timed-stands test was the method to quantify functional lower extremity muscle strength (hip and knee extension). The test requires the athlete to complete 10 full stands from a seated position as quickly as possible without the use of their arms. The athlete was seated in a firm straight-backed chair with the elbows flexed to 908 during the test. The athlete had to stand 10 times as quickly as possible and the time to perform the task in minutes and seconds was recorded. If the athlete could not perform 10 repetitions, the number of repetitions and the time taken was recorded. The TST is a reproducible measure of lower extremity function that was validated in people with disabilities. The reliability of this test can be found in Newcomer, Krug, and Mahowald (1993). Partial sit-up test (PSUT). The partial sit-up test was the method to quantify abdominal muscle strength/endurance. The test requires the athlete to complete as many sit-ups as possible from a supine position in one minute. The participant was positioned supine on a table or mat, with the legs placed on a chair or stool to keep their hips and knees bent at 908. Their arms were placed straight out in front of the chest with the elbows extended during the entire test. Test–retest reliability and validity was established in a previous study (Knudson, 2001). Seated push-up (SPU). The seated push-up test is a method of assessing the strength of the triceps, shoulder and scapular muscles. The test involves pushing the body up out of a seated position, and slowly lowering it back into the seat. The athlete was placed with the knees out straight and the heels resting on the floor or table. The athlete had to push their body up from the table or floor until the elbows were straight, held for 20 s and then slowly lowered back into the seat. The reliability of revised push-up test protocol in people without disabilities was 0.90–0.99 (Baumgartner, Oh, Chung, & Hales, 2002). Handgrip test (HGT). The handgrip test is a standardized method for assessing strength of the hand and forearm muscles, as it has been correlated to upper extremity function. The test involved completing three grips on each side (preferred and non preferred hand) and recording the better of the three trials using an adjustable handgrip dynamometer. The athlete had to keep the arm and hand at the side with the elbow bent at 908 while squeezing as forcefully as possible. The handgrip dynamometer have being found to be highly reliable (ICC = 0.98) and valid (ICC = 0.99) for measuring handgrip strength (Bellace, Healy, Besser, Byron, & Hohman, 2000). Single-leg stance with eyes open (SLSEO). The single-leg stance test with eyes open is designed to assess balance with the assistance of visual cues. The test required the athlete to stand on one leg with the eyes open. Balance must be maintained as
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long as possible. The arms were placed at the sides with elbows slightly flexed during the test. The test continued until athlete lost balance, or put the other foot down (maximum time was 30 s). Single-leg stance with eyes closed (SLSEC). The single-leg stance test with eyes closed is similar to the previous one but without the assistance of visual cues, so the athlete’s eyes are kept closed or covered with a blindfold. Interclass correlation coefficients were moderate to excellent (0.41–0.91) suggesting that the standing balance tests are appropriate for distinguishing among group performances (Birmingham, 2000). Functional reach test (FRT). The test requires the athlete to reach forward beyond the length of his/her arm without loss of balance. The participant was on two legs, positioned shoulder width apart (or seated if the athlete could not stand). The athlete was requested to lift one arm up to 908, forward flexion and extend fingers. Test–retest reliability and validity was established in a previous study (Duncan, Weiner, Chandler, & Studenski, 1990). Two-minute step test (2MST). Pre-exercise resting heart rate (RHR) was recorded with the athlete seated before the test and again two-minute after the test is finished (2MAF). The athlete was located next to a wall, and the minimum stepping height for the athlete was marked. The test required a running tape measure from the iliac crest to the mid-patella, and to mark the midway point on the tape. This mark was transferred to the wall. The athlete was requested to march for a maximum of 2 min, bringing each knee alternatively up to the tape mark in the wall. The number of times that the athlete touched the tape with the right knee was recorded. The 2MST showed a high inter-rater reliability (intraclass correlation coefficient [ICC] 0.90–0.96) and intra-rater reliability was also high (ICC 0.98–0.99) in subject with disabilities (Brooks et al., 2002). 2.3. Statistical analysis Descriptive statistics including measures of central tendency and dispersion were calculated for all outcome measures. Normal distribution was evaluated with the Kolmogorov–Smirnov’s test. Depending on the result either a t-test or a Wilconxon’s test was applied. Analysis was done using SPSS version 15.0. 2.4. Ethical issues The institutional review committees at the University of Malaga approved the procedures used in this study and ethical recommendations were taken into consideration at all stages during the research. All athletes and parents or guardians gave informed consent before participation. 3. Results Descriptive data and comparisons are presented in Tables 1 and 2. From a total number of 266 participants in the study, 118 participants declared themselves (or were reported by a parent/guardian) to practice physical activity or sport from 3 to Table 1 Statistical and mean differences in physical fitness variables of male and female athletes with intellectual disabilities. Mean SD
PKE_right (8) PKE_left (8) CMF_right (8) CMF_left (8) AHF_right (8) AHF_left (8) FSR_right (cm) FSR_left (cm) TST (s) PSUT (repetitions/1 m) SPU (s) HGT_mean_right (kg) HGT_mean_left (kg) SLSEO_right (s) SLSEO_left (s) SLSEC_right (s) SLSEC_left (s) FRT_right (cm) FRT_left (cm) RHR (bpm) 2MST(bpm) 2MAF(bpm) * ** ***
Mean difference between (95% CI)
Males (n = 187)
Females (n = 79)
22.26 15.60 21.24 15.63 6.61 7.66 6.24 8.83 7.40 6.97 7.87 6.72 9.43 12.99 12.05 12.20 19.92 9.48 31.43 24.41 18.97 9.65 29.01 11.15 28.32 10.35 16.72 14.93 17.93 15.97 6.67 9.2 7.34 9.58 36.37 9.88 36.21 19.16 84.58 15.15 123.35 21.57 89.19 16.84
16 15.83 13.86 14.96 8.92 8.61 7.95 10.51 4.42 6.5 4.73 5.37 9.08 10.50 11.33 10.08 22.77 9.71 25.59 12.07 14.05 10.89 17.73 7.74 16.29 7.26 13.54 14 23 12.82 14.02 3.53 4.59 3.43 4.23 34.23 8.47 33.97 9.43 83.32 17.5 118.24 25.01 85.73 20.85
0.05, significance level (t-test for independents samples). 0.01, significance level (t-test for independents samples). 0.001, significance level (t-test for independents samples).
6.21( 10.36 to 2.07)** 7.38( 11.4 to 3.35)*** 2.3( 4.41 to 0.20)* 1.74( 4.18 to 0.75) 2.97( 4.78 to 1.17)** 3.13( 4.81 to 145)*** 0.35( 3.61 to 2.89) 0.72( 3.57 to 2.12) 2.85( 5.37 to 0.35)* 5.83(0.14 to 11.52)* 4.91(2.25 to 7.57)*** 11.25(8.54 to 14.00)*** 12.03(9.41 to 14.65)*** 3.17( 0.74 to 7.1) 5.10(2.08 to 9.21)** 3.9(1.65 to 6.16)*** 3.14(0.95 to 5.33)** 2.14(1.27 to 4.65) 2.23(1.33 to 4.86) 1.26( 2.95 to 5.47) 3.05( 0.89 to 11.11) 3.45( 1.8 to 8.71)
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Table 2 Statistical and mean difference in physical fitness variables of athletes with intellectual disabilities as classified by frequency of physical activity. Mean SD
PKE_right (8) PKE_left (8) CMF_right (8) CMF_left (8) AHF_right (8) AHF_left (8) FSR_right (cm) FSR_left (cm) TST (s) PST (repetitions/1 m) SPU (s) HGT_mean_right (kg) HGT_mean_left (kg) SLSEO_right (s) SLSEO_left (s) SLSEC_right (s) SLSEC_left (s) FRT_right (cm) FRT_left (cm) RHR (bpm) 2MST(bpm) 2MAF(bpm) **
Mean difference between (95% CI)
Sportspersons (n = 118)
Non sportspersons (n = 148)
17.38 15.59 16.44 15.94 8.06 7.87 7.16 9.14 6.57 6.45 6.73 6.23 8.07 11.3 12.03 11.82 20.14 8.54 29.63 12.97 18.71 9.77 25.87 10.7 24.6711.28 16.99 14.82 16.79 15.61 5.48 8.48 6.05 8.72 36.38 8.69 36.37 9.40 82.70 12.36 123.77 20.94 86.77 16.36
23.17 15.75 21.44 15.34 6.76 8.13 6.45 9.61 6.42 7.28 7.19 6.64 10.28 13.06 11.61 11.52 21.51 10.28 29.83 26.62 16.73 10.57 25.86 25.13 11.29 15.20 14.83 16.35 15.56 5.97 8.05 6.30 8.42 35.54 9.7 34.96 10.01 86.12 16.74 120.86 21.92 89.85 18.03
5.78(1.95 to 9. 2.07)** 4.99(1.18 to 8.8)** 0.99( 065 to 3.25) 0.71( 1.58 to 3.0) 0.03( 1.72 to 1.65) 0.46( 1.70 to 1.63) 2.21( 0.79 to 5.21) 0.41( 3.25 to 2.43) 1.37( 3.7 to 0.95) 0.19( 5.5 to 5.1) 1.98(0.53 to 4.49) 0.95( 3.68 to 1.77) 0.61( 2.74 to 2.62) 1.78( 34 to 4.27) 0.43( 3.4 to 4.27) 0.48( 2.53 to 1.54) 0.25( 2.37 to 1.87) 0.83( 1.4 to 3.11) 1.78( 061 to 4.17) 3.41( 7.08 to 0.26) 2.92( 2.37 to 8.18) 3.08( 7.33 to 1.16)
0.01, significance level (t-test for independents samples).
7 h per week (44.3%). These participants were considered in this study as sportspeople, including 83 males and 35 females. The other 148 individuals (55.6%) reported to practice physical activity or sport from 1 to 2 h per week, and were considered as non sportspeople. From those, 102 were males and 46 were females. With regard to the scores and gender, males scored higher in flexibility tests PKE, AHF, and FSR, all on both sides and females scored higher in CMF tests, on both sides. Males scored higher in strength/endurance tests such as the TST, the PSUT, the SPUT and the HGT, all on both sides. Scores in the three balance tests were also higher for males. Values in seconds were higher for males in the SLSEO, both sides, and also in the SLSEC, both sides, than female scores. In the FRT test, the distance reached beyond the length of the arm without loss of balance was longer for male participants. 2MST and 2MAF scores were better for males, but the differences were not statistically significant. With regard to the comparison of the scores between the most physically active participants (sportspeople) and less active participants (non sportspeople), it has been found that the scores were quite similar, with slight differences depending on the evaluated side. Scores were better for the sportspeople in the flexibility tests such as the PKE (both sides) and the CMF (both sides). The values regarding flexibility were also better in the AHF test on the left side but slightly worse in the AHF test on the right side. The opposite was found in the scores for the FSR test, which were slightly worse for the sportspeople in the FSR test on the left side. Regarding to the strength/endurance, the sportspeople scored better in the TST, the PSUT and the HGT tests on the right side but slightly worse in the PST and the HGT on the left side. Values were better for the sportspeople in the balance tests such as the FRT (both sides) and the SLSEC (both sides), but the non sportspeople scored slightly better for the SLSEC test (both sides). 4. Discussion In this study, the fitness level of athletes with intellectual disabilities is described and scores are compared in relation to their level of regular physical activity. Among the findings, the first issue to take into consideration is that the number of participants that were classified as more physically active (from 3 to 7 h per week of practice) was lower than the less physically active (from 1 to 2 h per week of practice), although all of them were recruited in a national sport competition game. This is maybe due to the fact that the Special Olympic Games are not considered a sport competition for elite athletes with ID. The athletes may have diverse fitness profile because there is not a need for any previous qualification or performance standards that require specific regular training. Another aspect to take in consideration regarding the cohort in this study is that the number of female participants was much lower than male participants. These differences have also appeared in other studies regarding physical fitness of individuals with ID where participants were recruited during competition games (Van de Vliet et al., 2006) or in special schools (Skowronski et al., 2009). It has been shown that scores in fitness tests are influenced by gender, age level of intellectual disability (Skowronski et al., 2009), so the gender variable has also been considered in the data comparison. Regarding the age, the participants in
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this study were young adults with mild ID (31.1 7.5 years old) with diverse level of practice of physical activity. It is known that balance and strength in individuals with ID is considered to decline during adulthood, when also other health risks may appear such as of overweight and obesity (Lahtiner, Rintala, & Malin, 2007). But aspects such as body weight and BMI of participants have not been taken into consideration although they may have influenced the fitness test scores (Guidetti, Franciosi, Gallorta, Emerenziani, & Baldari, 2010). Balance capabilities are particularly relevant to be checked in individuals with ID, because it is one of the risk factors for falling. Studies that have analysed the balance capabilities in individuals with ID have found slow motor responses to postural perturbations (Hale, Bray, & Littmann, 2007). Other authors (Dellavia, Pallavera, Orlando, & Sforza, 2009) have found differences in body balance in a study with 60 Special Olympics athletes in comparison with 30 adults without ID. Participants without ID oscillated less than those with ID. From the group with ID those with Down syndrome had larger body sway than those without this condition highlighting that the differences in the scores can be related to the type and level of ID, also stated in other research (Franciosi, Baldari, Gallotta, Emerenciani, & Guidetti, 2010; Skowronski et al., 2009). Participants in our study were athletes with mild intellectual disabilities whose were placed into categories by level of activity and gender but not by the type of intellectual disability. This factor could be taken into account in future research, as the issue of recruiting similar number of males and females to better identify the gender influence. Regarding the scores by gender, female participants scored better for flexibility tests, an expected outcome because flexibility is a gender-related variable. This phenomenon has already been found in other previous studies using the Eurofit Special tests with ID participants. Male athletes in this study scored better than female for strength/endurance and balance, and this outcome has also been found using the Eurofit Special tests (Skowronski et al., 2009). The scores in the fitness tests between the sportspeople and non sportspeople groups, were quite similar but slightly better for the sportspeople in most of the tests. Nevertheless, differences were not meaningfully different in strength, in balance, aerobic condition, and in flexibility with the exception of the PKE test for flexibility. Previous studies using the EUROFIT tests to investigate the physical fitness of elite athletes in comparison with age-matched physical education students have showed similar or lower scores for individuals with ID (Van de Vliet et al., 2006). They found that for males (231 participants), the athletes with ID scored better in flexibility than the students but worse in strength. In the female group (82 participants), the athletes with ID had similar scores in flexibility but worse in strength when compare with the students’ group. For these authors this data in general supports the fact that individuals with ID have limited physical capacities, especially with regard to strength measures. Regarding the limitations of our study, we understand that the findings presented are related to the scores collected through the previously described tests. Those tests are considered to be reliable to evaluate physical fitness in massive groups in community settings. Nevertheless, we assume that other scores could maybe appear using other specific tests to evaluate physical fitness in individuals with ID. 5. Conclusion The findings in this study illustrate an unclear and inconclusive relation between the scores and the declared level of physical activity, maybe due to the context in which participants for the study were selected. Further studies could help to determine the concept of fitness in this specific population, with practical applications for the establishment of appropriate community programmes addressed to improve the health status of people with ID. Other research could be developed to better identify the level of physical activity and fitness profile in individuals with ID. Longitudinal studies are also necessary for a long-term documentation of the performance of individuals with ID. Randomised controlled trials could be performed to evaluate the influence of specifically designed exercises in the improvement of physical fitness and therefore in the functional tasks of daily living. Acknowledgments The authors would like to thank all participants, collaborating physiotherapist and volunteers. This research was partially funded by grants from the OTRI-UMA ref 806/423505 cod 00334 (A.I. Cuesta-Vargas, PI). References Angelopoulou, N., Matziari, C., Tsimaras, V., Sakadamis, A., Souftas, V., & Mandroukas, K. (2000). Bone mineral density and muscle strength in young men with mental retardation (with and without Down syndrome). Calcified Tissue International, 66(3), 176–180. Angelopoulou, N., Tsimaras, V., Christoulas, K., Kokaridas, D., & Mandroukas, K. (1999). Isokinetic knee muscle strength of individuals with mental retardation, a comparative study. Perceptual and Motor Skills, 88(3 Pt 1), 849–855. Baumgartner, T. A., Oh, S., Chung, H., & Hales, D. (2002). Objectivity, reliability, and validity for a revised push-up test protocol. Measurement in Physical Education and Exercise Science, 6(4), 225–242. Beasley, C. R. (1982). Effects of a jogging program on cardiovascular fitness and work performance of mentally retarded adults. American Journal of Mental Deficiency, 86(6), 609–613. Bellace, J. V., Healy, D., Besser, M. P., Byron, T., & Hohman, L. (2000). Validity of the Dexter evaluation system’s Jamar dynamometer attachment for assessment of hand grip strength in a normal population. Journal of Hand Therapy, 13, 46–51. Birmingham, T. B. (2000). Test–retest reliability of lower extremity functional instability measures. Clinical Journal of Sport Medicine, 10, 264–268. Bostro¨m, C., Harms-Ringdahl, K., & Nordemar, R. (1991). Clinical reliability of shoulder function assessment in patients with rheumatoid arthritis. Scandinavian Journal of Rheumatology, 20(1), 36–48.
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Contents lists available at ScienceDirect
Research in Developmental Disabilities
Physical fitness profile in adults with intellectual disabilities: Differences between levels of sport practice Antonio Ignacio Cuesta-Vargas a,*, Berta Paz-Lourido b, Alejandro Rodriguez c a
Department of Physiotherapy, University of Malaga, Av de Martiricos s/n, 29071 Malaga, Spain Department of Nursing and Physiotherapy, University of the Balearic Islands, Beatriu de Pino´s Building, Cra. De Valldemossa, km 7.5, 07122 Palma de Mallorca, Spain c National Health Service of Castilla de la Mancha, Spain b
A R T I C L E I N F O
A B S T R A C T
Article history: Received 26 October 2010 Accepted 28 October 2010 Available online 15 December 2010
Neuromuscular and aerobic capacity can be reduced in people with intellectual disabilities (ID). Previous studies suggest these individuals might be particularly susceptible to losing basic functions because of poor physical fitness. The aim of this study is to describe the physical fitness profile of adult athletes with ID and identify whether there are differences in the physical performance between the most physically active individuals and less active individuals. A cross-sectional observational study was developed involving 266 athletes with mild ID (187 males and 79 females), recruited from the Spanish Special Olympics Games. A questionnaire was used to evaluate the health status of participants and their frequency of physical activity practice. A battery of 13 fitness tests was applied to assess flexibility, strength/endurance, balance and cardiovascular capabilities. Of the total participants, 44.3% were classified as sportspersons and the remainder as non sportspersons, taking in consideration the frequency of physical activity. Regarding the scores, a significant difference was found in degrees of flexibility between genders, higher for females for one test but higher for males in the other three. A significant difference was not encountered between other variables of physical fitness, although the men’s scores were higher in strength/endurance and balance. When the scores of the sportspersons and non sportspersons groups were compared, no significant difference was found between the two, with the exception of one test for flexibility. Differences among groups and gender were not statistically significant in most of the tests. The findings in this study illustrate an unclear and inconclusive relation between the scores and the declared level of physical activity, maybe due to the context in which participants for the study were selected. ß 2010 Elsevier Ltd. All rights reserved.
Keywords: Physical fitness Intellectual disabilities Sport Musculoskeletal development
1. Introduction The fitness of adults with intellectual disabilities (ID) has been found to be significantly weaker than in individuals without ID at all stages of life (Angelopoulou, Tsimaras, Christoulas, Kokaridas, & Mandroukas, 1999; Angelopoulou et al., 2000; Carmeli, Ayalon, Barchad, Sheklow, & Reznick, 2002; Carmeli, Barchad, Lenger, & Coleman, 2002; Carmeli, Kessel, Coleman, & Ayalon, 2002; Croce, Pitetti, Horvat, & Miller, 1996; Horvat, Pitetti, & Croce, 1997; Pitetti & Boneh, 1995; Pitetti, Climstein, Mays, & Barrett, 1992; Skowronski, Horvat, Nocera, Roswal, & Croce, 2009). Neuromuscular and aerobic capacity can be severely reduced in adults with intellectual disabilities (Fernhall & Pitetti, 2001), suggesting that these individuals
* Corresponding author. Tel.: +34 952137551; fax: +34 971172309. E-mail addresses: [email protected], [email protected] (A.I. Cuesta-Vargas), [email protected] (B. Paz-Lourido), [email protected] (A. Rodriguez). 0891-4222/$ – see front matter ß 2010 Elsevier Ltd. All rights reserved. doi:10.1016/j.ridd.2010.10.023
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might be particularly susceptible to a loss of basic functioning because of poor physical fitness (Carmeli, Barchad, et al., 2002; Pitetti & Boneh, 1995). Despite the benefits of physical activity in balance, strength, endurance and health self-perception (Carmeli, ZingerVaknin, Morad, & Merrick, 2005), physical fitness has been further related to job opportunities and vocational performance in adults with ID (Beasley, 1982; Croce & Horvat, 1992; Horvat & Croce, 1995). Other studies with adults with ID show the positive influence of employment that requires competitive and high functional work ability, illustrating the relevance of physical activity in many spheres of life for broader wellbeing (Kober & Eggleton, 2005; Stephens, Collins, & Dodder, 2005). The demonstrated link between physical fitness and time performance of functional tasks of daily living in adults with ID (Cowley et al., 2010) suggests the importance of studies on the topic. The participation of children and adults with disabilities in sports and recreational activities has often been addressed to enhance overall wellbeing and promote social inclusion (Wilson, 2002). However, some barriers to their active participation in regular exercise have been identified. The individual’s functional limitations, the high costs or the lack of nearby facilities or programmes are some of the reasons for nonparticipation (King et al., 2003). Some literature suggests that many individuals with ID have poor adherence to physical activity programs or sports (McGuire, Daly, & Smyth, 2007), what puts this group at relatively high risk for the development of multiple negative consequences of a sedentary lifestyle (Lotan, Isakov, Kessel, & Merrick, 2004). Nevertheless, data on this topic seems to be insufficient to determine whether individuals with ID are currently less active than their peers without disabilities (Frey, Stanish, & Temple, 2008; Temple, Frey, & Stanish, 2006). Among the institutions that promote wellbeing and empower people with ID through sports, the Special Olympics organisation (www.specialolympics.com) offers the largest selection of recreational activities, including national and international competitive sport games. Special Olympics also develops diverse healthcare programmes aimed to screen the health status of athletes and give them and their families support when needed. One of this is the FUNFitness programme, which provides screenings to evaluate the physical status of the participants in the games and offers them practical suggestions to improve their health condition and avoid injuries. After the screening, all athletes are provided with specific information regarding their physical profile. Health education with emphasis in musculoskeletal issues is also given, using educational materials tailored for people with lower reading levels when necessary. The impact of Special Olympics games in the participants’ health status has been studied at psychosocial and physical level. Besides the consideration of sport as a significant life experience for the special olympians (Mharada & Siperstein, 2009), they may benefit in perceived competence, self-awareness and social acceptance (Gibbons & Bushakra, 1989; Weiss, Diamond, Demark, & Lovald, 2003). However, the impact of the games in increasing the physical profile of participants seems to be low if it is not accompanied by regular training (Machek, Stopka, Tillman, Sneed, & Naugle, 2008; Pitteti, Jackson, Stubbs, Campbell, & Saraswathy, 1989). With this research we aimed to describe the physical fitness profile of adult athletes with ID and identify whether there are differences in the physical performance between the most physically active individuals (sportspeople) and the less active individuals (non sportspeople). 2. Material and methods 2.1. Participants Participants in this study were 266 individuals with ID (187 males and 79 females) recruited from the Spanish Special Olympics Games. The mean age of participants was 31.1 with a standard deviation of 7.5 years. All participants had been medically diagnosed with a mild intellectual disability. General issues regarding the health status were checked before participation in the study and data regarding their health history was obtained from the participants and their parents and/or guardians. This health history included questions regarding the level of adherence to sports or regular physical activities. The hours per week the athletes practice physical activity or sport were recorded to classify the participants regarding their activeness. The participants were identified as sportspeople when they practiced physical activities from 3 to 7 h per week, and a non sportspeople when they practiced from 1 to 2 h per week. Exclusion criteria to participate in the study included: (1) any contraindications to exercise as assessed by a medical history questionnaire, (2) documented atherosclerotic heart disease, (3) documented atlantoaxial instability, (4) uncorrected congenital heart disease, and (5) implanted pacemaker. 2.2. Study design and instruments This cross-sectional observational study employed a battery of 13 fitness tests including: the passive knee extension test, the calf muscle flexibility test, the anterior hip flexibility test, the functional shoulder rotation test, the timed-stand test, the partial sit-up test, the seated push-up, the grip test, the single leg stance open and closed eyes, and the 3 min walk test. A detailed description of the tests and data regarding reliability is given in this section. The examiners were 10 qualified physiotherapists and 15 trained physiotherapy students from the residency programmes. A four-hour training session was previously developed for the examiners to become acquainted with the specific fitness tests to be used. Other aspects regarding social interaction with individuals with ID were included in the
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training session. Due to the importance for the athletes to comprehend what was required from them during the screening, special emphasis was given to communication issues. Tests were explained to the athletes and repeated several times if necessary. Quite frequently, examiners had to demonstrate how to perform the tests to check that the participants indeed understood what was required from them. Tests were performed with at least two examiners to assure that the measure was done correctly but also to give support, to encourage and to ensure the safety of the athletes during the tests performance. Passive knee extension (PKE). The athlete was positioned supine on a treatment table with hip and knee flexed at 908. The passive knee extension was measured using a goniometer, with the fulcrum placed over the lateral femoral epicondyle and its arms in the direction of the greater trochanter and lateral malleolus, respectively. Their ankle remained in a neutral position or in plantarflexion. If the knee was fully extended, the final value was recorded as 08. If the knee didn’t extend, the value was recorded as negative (e.g., 408). If the knee went beyond the fully straight position into hyperextension, the value was recorded as positive (e.g., +58). The reliability of the PKE test was explored and compared with other clinical tests for assessing hamstring muscle as proposed by Gajdoski, Rieck, Sullivan, and Wightman (1993). Calf muscle flexibility (CMF). The athlete was positioned supine on a table, with the hip and knee on the side to be measured in as much extension as possible. The fulcrum of the goniometer was placed over the lateral malleolus, with one of its arms in the direction of the fibular head and the other one in parallel to the lateral midline of the fifth metatarsal. Their ankle was passively dorsiflexed and its angle measured while their knee remained in extension. If the athlete couldn’t reach neutral position, the angle was recorded as negative (e.g., 108). If the athlete went beyond neutral, it was recorded as positive (e.g., +108). If the athlete only reached neutral, it was recorded as 08. The reliability of this test can be found in Ekstrand, Wiktorsonn, Oberg, and Gilquist (1982). Anterior hip flexibility (AHF). The athlete was positioned supine on a table, both hips flexed to 908. The hip to be measured was flexed up to 1008 with a hand beneath the lower back to ensure that it remained flattened. Opposite hip was kept at 908 and not allowed to move into extension during the test. The fulcrum of the goniometer was placed over the greater trochanter, with its arms aligned with the lateral midline of the pelvis and with the lateral midline of the femur, respectively. The degrees of extension between the pelvis and thigh were measured before the pelvis began to move forward. If the thigh lowered to the table surface, the result was recorded as 08. If the thigh didn’t reach the table, the angle was recorded as negative (e.g., 258). The reliability of this test can be found in Ekstrand et al. (1982). Functional shoulder rotation (FSR). The athlete stood or was seated facing the back of a chair. The athlete was instructed to reach one arm behind the head and down the back, while the other arm reached behind the hip and up the back. The athlete was instructed to ‘‘try to touch their index fingers together.’’ A tape measure was used to measure the distance in cm between the index fingers in this position (one arm was in flexion/abduction/lateral rotation; the other was in extension/ adduction/medial rotation). The arm on top defined the recorded side (i.e., left arm on top = left; right arm on top = right). If the fingertips touched, the distance was recorded as 0. If the fingertips could not touch, the separation was recorded as negative (e.g., 15.2 cm). If the fingers overlap, the overlap was recorded as positive (e.g., +2.5 cm). The FSR is a reproducible measure of upper extremity function task that was validated in people with disabilities. The reliability of this test can be found in Bostro¨m, Harms-Ringdahl, and Nordemar (1991). The timed-stands test (TST). The timed-stands test was the method to quantify functional lower extremity muscle strength (hip and knee extension). The test requires the athlete to complete 10 full stands from a seated position as quickly as possible without the use of their arms. The athlete was seated in a firm straight-backed chair with the elbows flexed to 908 during the test. The athlete had to stand 10 times as quickly as possible and the time to perform the task in minutes and seconds was recorded. If the athlete could not perform 10 repetitions, the number of repetitions and the time taken was recorded. The TST is a reproducible measure of lower extremity function that was validated in people with disabilities. The reliability of this test can be found in Newcomer, Krug, and Mahowald (1993). Partial sit-up test (PSUT). The partial sit-up test was the method to quantify abdominal muscle strength/endurance. The test requires the athlete to complete as many sit-ups as possible from a supine position in one minute. The participant was positioned supine on a table or mat, with the legs placed on a chair or stool to keep their hips and knees bent at 908. Their arms were placed straight out in front of the chest with the elbows extended during the entire test. Test–retest reliability and validity was established in a previous study (Knudson, 2001). Seated push-up (SPU). The seated push-up test is a method of assessing the strength of the triceps, shoulder and scapular muscles. The test involves pushing the body up out of a seated position, and slowly lowering it back into the seat. The athlete was placed with the knees out straight and the heels resting on the floor or table. The athlete had to push their body up from the table or floor until the elbows were straight, held for 20 s and then slowly lowered back into the seat. The reliability of revised push-up test protocol in people without disabilities was 0.90–0.99 (Baumgartner, Oh, Chung, & Hales, 2002). Handgrip test (HGT). The handgrip test is a standardized method for assessing strength of the hand and forearm muscles, as it has been correlated to upper extremity function. The test involved completing three grips on each side (preferred and non preferred hand) and recording the better of the three trials using an adjustable handgrip dynamometer. The athlete had to keep the arm and hand at the side with the elbow bent at 908 while squeezing as forcefully as possible. The handgrip dynamometer have being found to be highly reliable (ICC = 0.98) and valid (ICC = 0.99) for measuring handgrip strength (Bellace, Healy, Besser, Byron, & Hohman, 2000). Single-leg stance with eyes open (SLSEO). The single-leg stance test with eyes open is designed to assess balance with the assistance of visual cues. The test required the athlete to stand on one leg with the eyes open. Balance must be maintained as
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long as possible. The arms were placed at the sides with elbows slightly flexed during the test. The test continued until athlete lost balance, or put the other foot down (maximum time was 30 s). Single-leg stance with eyes closed (SLSEC). The single-leg stance test with eyes closed is similar to the previous one but without the assistance of visual cues, so the athlete’s eyes are kept closed or covered with a blindfold. Interclass correlation coefficients were moderate to excellent (0.41–0.91) suggesting that the standing balance tests are appropriate for distinguishing among group performances (Birmingham, 2000). Functional reach test (FRT). The test requires the athlete to reach forward beyond the length of his/her arm without loss of balance. The participant was on two legs, positioned shoulder width apart (or seated if the athlete could not stand). The athlete was requested to lift one arm up to 908, forward flexion and extend fingers. Test–retest reliability and validity was established in a previous study (Duncan, Weiner, Chandler, & Studenski, 1990). Two-minute step test (2MST). Pre-exercise resting heart rate (RHR) was recorded with the athlete seated before the test and again two-minute after the test is finished (2MAF). The athlete was located next to a wall, and the minimum stepping height for the athlete was marked. The test required a running tape measure from the iliac crest to the mid-patella, and to mark the midway point on the tape. This mark was transferred to the wall. The athlete was requested to march for a maximum of 2 min, bringing each knee alternatively up to the tape mark in the wall. The number of times that the athlete touched the tape with the right knee was recorded. The 2MST showed a high inter-rater reliability (intraclass correlation coefficient [ICC] 0.90–0.96) and intra-rater reliability was also high (ICC 0.98–0.99) in subject with disabilities (Brooks et al., 2002). 2.3. Statistical analysis Descriptive statistics including measures of central tendency and dispersion were calculated for all outcome measures. Normal distribution was evaluated with the Kolmogorov–Smirnov’s test. Depending on the result either a t-test or a Wilconxon’s test was applied. Analysis was done using SPSS version 15.0. 2.4. Ethical issues The institutional review committees at the University of Malaga approved the procedures used in this study and ethical recommendations were taken into consideration at all stages during the research. All athletes and parents or guardians gave informed consent before participation. 3. Results Descriptive data and comparisons are presented in Tables 1 and 2. From a total number of 266 participants in the study, 118 participants declared themselves (or were reported by a parent/guardian) to practice physical activity or sport from 3 to Table 1 Statistical and mean differences in physical fitness variables of male and female athletes with intellectual disabilities. Mean SD
PKE_right (8) PKE_left (8) CMF_right (8) CMF_left (8) AHF_right (8) AHF_left (8) FSR_right (cm) FSR_left (cm) TST (s) PSUT (repetitions/1 m) SPU (s) HGT_mean_right (kg) HGT_mean_left (kg) SLSEO_right (s) SLSEO_left (s) SLSEC_right (s) SLSEC_left (s) FRT_right (cm) FRT_left (cm) RHR (bpm) 2MST(bpm) 2MAF(bpm) * ** ***
Mean difference between (95% CI)
Males (n = 187)
Females (n = 79)
22.26 15.60 21.24 15.63 6.61 7.66 6.24 8.83 7.40 6.97 7.87 6.72 9.43 12.99 12.05 12.20 19.92 9.48 31.43 24.41 18.97 9.65 29.01 11.15 28.32 10.35 16.72 14.93 17.93 15.97 6.67 9.2 7.34 9.58 36.37 9.88 36.21 19.16 84.58 15.15 123.35 21.57 89.19 16.84
16 15.83 13.86 14.96 8.92 8.61 7.95 10.51 4.42 6.5 4.73 5.37 9.08 10.50 11.33 10.08 22.77 9.71 25.59 12.07 14.05 10.89 17.73 7.74 16.29 7.26 13.54 14 23 12.82 14.02 3.53 4.59 3.43 4.23 34.23 8.47 33.97 9.43 83.32 17.5 118.24 25.01 85.73 20.85
0.05, significance level (t-test for independents samples). 0.01, significance level (t-test for independents samples). 0.001, significance level (t-test for independents samples).
6.21( 10.36 to 2.07)** 7.38( 11.4 to 3.35)*** 2.3( 4.41 to 0.20)* 1.74( 4.18 to 0.75) 2.97( 4.78 to 1.17)** 3.13( 4.81 to 145)*** 0.35( 3.61 to 2.89) 0.72( 3.57 to 2.12) 2.85( 5.37 to 0.35)* 5.83(0.14 to 11.52)* 4.91(2.25 to 7.57)*** 11.25(8.54 to 14.00)*** 12.03(9.41 to 14.65)*** 3.17( 0.74 to 7.1) 5.10(2.08 to 9.21)** 3.9(1.65 to 6.16)*** 3.14(0.95 to 5.33)** 2.14(1.27 to 4.65) 2.23(1.33 to 4.86) 1.26( 2.95 to 5.47) 3.05( 0.89 to 11.11) 3.45( 1.8 to 8.71)
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Table 2 Statistical and mean difference in physical fitness variables of athletes with intellectual disabilities as classified by frequency of physical activity. Mean SD
PKE_right (8) PKE_left (8) CMF_right (8) CMF_left (8) AHF_right (8) AHF_left (8) FSR_right (cm) FSR_left (cm) TST (s) PST (repetitions/1 m) SPU (s) HGT_mean_right (kg) HGT_mean_left (kg) SLSEO_right (s) SLSEO_left (s) SLSEC_right (s) SLSEC_left (s) FRT_right (cm) FRT_left (cm) RHR (bpm) 2MST(bpm) 2MAF(bpm) **
Mean difference between (95% CI)
Sportspersons (n = 118)
Non sportspersons (n = 148)
17.38 15.59 16.44 15.94 8.06 7.87 7.16 9.14 6.57 6.45 6.73 6.23 8.07 11.3 12.03 11.82 20.14 8.54 29.63 12.97 18.71 9.77 25.87 10.7 24.6711.28 16.99 14.82 16.79 15.61 5.48 8.48 6.05 8.72 36.38 8.69 36.37 9.40 82.70 12.36 123.77 20.94 86.77 16.36
23.17 15.75 21.44 15.34 6.76 8.13 6.45 9.61 6.42 7.28 7.19 6.64 10.28 13.06 11.61 11.52 21.51 10.28 29.83 26.62 16.73 10.57 25.86 25.13 11.29 15.20 14.83 16.35 15.56 5.97 8.05 6.30 8.42 35.54 9.7 34.96 10.01 86.12 16.74 120.86 21.92 89.85 18.03
5.78(1.95 to 9. 2.07)** 4.99(1.18 to 8.8)** 0.99( 065 to 3.25) 0.71( 1.58 to 3.0) 0.03( 1.72 to 1.65) 0.46( 1.70 to 1.63) 2.21( 0.79 to 5.21) 0.41( 3.25 to 2.43) 1.37( 3.7 to 0.95) 0.19( 5.5 to 5.1) 1.98(0.53 to 4.49) 0.95( 3.68 to 1.77) 0.61( 2.74 to 2.62) 1.78( 34 to 4.27) 0.43( 3.4 to 4.27) 0.48( 2.53 to 1.54) 0.25( 2.37 to 1.87) 0.83( 1.4 to 3.11) 1.78( 061 to 4.17) 3.41( 7.08 to 0.26) 2.92( 2.37 to 8.18) 3.08( 7.33 to 1.16)
0.01, significance level (t-test for independents samples).
7 h per week (44.3%). These participants were considered in this study as sportspeople, including 83 males and 35 females. The other 148 individuals (55.6%) reported to practice physical activity or sport from 1 to 2 h per week, and were considered as non sportspeople. From those, 102 were males and 46 were females. With regard to the scores and gender, males scored higher in flexibility tests PKE, AHF, and FSR, all on both sides and females scored higher in CMF tests, on both sides. Males scored higher in strength/endurance tests such as the TST, the PSUT, the SPUT and the HGT, all on both sides. Scores in the three balance tests were also higher for males. Values in seconds were higher for males in the SLSEO, both sides, and also in the SLSEC, both sides, than female scores. In the FRT test, the distance reached beyond the length of the arm without loss of balance was longer for male participants. 2MST and 2MAF scores were better for males, but the differences were not statistically significant. With regard to the comparison of the scores between the most physically active participants (sportspeople) and less active participants (non sportspeople), it has been found that the scores were quite similar, with slight differences depending on the evaluated side. Scores were better for the sportspeople in the flexibility tests such as the PKE (both sides) and the CMF (both sides). The values regarding flexibility were also better in the AHF test on the left side but slightly worse in the AHF test on the right side. The opposite was found in the scores for the FSR test, which were slightly worse for the sportspeople in the FSR test on the left side. Regarding to the strength/endurance, the sportspeople scored better in the TST, the PSUT and the HGT tests on the right side but slightly worse in the PST and the HGT on the left side. Values were better for the sportspeople in the balance tests such as the FRT (both sides) and the SLSEC (both sides), but the non sportspeople scored slightly better for the SLSEC test (both sides). 4. Discussion In this study, the fitness level of athletes with intellectual disabilities is described and scores are compared in relation to their level of regular physical activity. Among the findings, the first issue to take into consideration is that the number of participants that were classified as more physically active (from 3 to 7 h per week of practice) was lower than the less physically active (from 1 to 2 h per week of practice), although all of them were recruited in a national sport competition game. This is maybe due to the fact that the Special Olympic Games are not considered a sport competition for elite athletes with ID. The athletes may have diverse fitness profile because there is not a need for any previous qualification or performance standards that require specific regular training. Another aspect to take in consideration regarding the cohort in this study is that the number of female participants was much lower than male participants. These differences have also appeared in other studies regarding physical fitness of individuals with ID where participants were recruited during competition games (Van de Vliet et al., 2006) or in special schools (Skowronski et al., 2009). It has been shown that scores in fitness tests are influenced by gender, age level of intellectual disability (Skowronski et al., 2009), so the gender variable has also been considered in the data comparison. Regarding the age, the participants in
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this study were young adults with mild ID (31.1 7.5 years old) with diverse level of practice of physical activity. It is known that balance and strength in individuals with ID is considered to decline during adulthood, when also other health risks may appear such as of overweight and obesity (Lahtiner, Rintala, & Malin, 2007). But aspects such as body weight and BMI of participants have not been taken into consideration although they may have influenced the fitness test scores (Guidetti, Franciosi, Gallorta, Emerenziani, & Baldari, 2010). Balance capabilities are particularly relevant to be checked in individuals with ID, because it is one of the risk factors for falling. Studies that have analysed the balance capabilities in individuals with ID have found slow motor responses to postural perturbations (Hale, Bray, & Littmann, 2007). Other authors (Dellavia, Pallavera, Orlando, & Sforza, 2009) have found differences in body balance in a study with 60 Special Olympics athletes in comparison with 30 adults without ID. Participants without ID oscillated less than those with ID. From the group with ID those with Down syndrome had larger body sway than those without this condition highlighting that the differences in the scores can be related to the type and level of ID, also stated in other research (Franciosi, Baldari, Gallotta, Emerenciani, & Guidetti, 2010; Skowronski et al., 2009). Participants in our study were athletes with mild intellectual disabilities whose were placed into categories by level of activity and gender but not by the type of intellectual disability. This factor could be taken into account in future research, as the issue of recruiting similar number of males and females to better identify the gender influence. Regarding the scores by gender, female participants scored better for flexibility tests, an expected outcome because flexibility is a gender-related variable. This phenomenon has already been found in other previous studies using the Eurofit Special tests with ID participants. Male athletes in this study scored better than female for strength/endurance and balance, and this outcome has also been found using the Eurofit Special tests (Skowronski et al., 2009). The scores in the fitness tests between the sportspeople and non sportspeople groups, were quite similar but slightly better for the sportspeople in most of the tests. Nevertheless, differences were not meaningfully different in strength, in balance, aerobic condition, and in flexibility with the exception of the PKE test for flexibility. Previous studies using the EUROFIT tests to investigate the physical fitness of elite athletes in comparison with age-matched physical education students have showed similar or lower scores for individuals with ID (Van de Vliet et al., 2006). They found that for males (231 participants), the athletes with ID scored better in flexibility than the students but worse in strength. In the female group (82 participants), the athletes with ID had similar scores in flexibility but worse in strength when compare with the students’ group. For these authors this data in general supports the fact that individuals with ID have limited physical capacities, especially with regard to strength measures. Regarding the limitations of our study, we understand that the findings presented are related to the scores collected through the previously described tests. Those tests are considered to be reliable to evaluate physical fitness in massive groups in community settings. Nevertheless, we assume that other scores could maybe appear using other specific tests to evaluate physical fitness in individuals with ID. 5. Conclusion The findings in this study illustrate an unclear and inconclusive relation between the scores and the declared level of physical activity, maybe due to the context in which participants for the study were selected. Further studies could help to determine the concept of fitness in this specific population, with practical applications for the establishment of appropriate community programmes addressed to improve the health status of people with ID. Other research could be developed to better identify the level of physical activity and fitness profile in individuals with ID. Longitudinal studies are also necessary for a long-term documentation of the performance of individuals with ID. Randomised controlled trials could be performed to evaluate the influence of specifically designed exercises in the improvement of physical fitness and therefore in the functional tasks of daily living. Acknowledgments The authors would like to thank all participants, collaborating physiotherapist and volunteers. This research was partially funded by grants from the OTRI-UMA ref 806/423505 cod 00334 (A.I. Cuesta-Vargas, PI). References Angelopoulou, N., Matziari, C., Tsimaras, V., Sakadamis, A., Souftas, V., & Mandroukas, K. (2000). Bone mineral density and muscle strength in young men with mental retardation (with and without Down syndrome). Calcified Tissue International, 66(3), 176–180. Angelopoulou, N., Tsimaras, V., Christoulas, K., Kokaridas, D., & Mandroukas, K. (1999). Isokinetic knee muscle strength of individuals with mental retardation, a comparative study. Perceptual and Motor Skills, 88(3 Pt 1), 849–855. Baumgartner, T. A., Oh, S., Chung, H., & Hales, D. (2002). 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