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PubMed2005

Reliability of simple portable tests of physical performance in older people after hip fracture.

OBJECTIVE: To investigate the test-retest reliability of measures of strength, balance, gait and functional performance when used with older people following hip fracture. SUBJECTS: Thirty people (16 hospital inpatients and 14 community dwellers). DESIGN: Subjects underwent two assessments: one day apart for the hospital inpatients and one week apart for the community dwellers. MEASUREMENT: Strength (dynamometer, sphygmomanometer, spring balance, lateral step-up ability), balance (sway-meter, Functional Reach Test, single leg stance time, Step Test), gait (timed 6-m walk with steps taken, base of support and step length), and functional performance (PPME total score and timed supine-to-sit and sit-to-stand) were measured. RESULTS: Eleven of the 14 continuously scaled measurement tools achieved excellent reliability (intraclass correlation coefficient (ICC) > 0.75) for one or more tests. A hand-held dynamometer was found to be the tool with the highest test-retest reliability for measuring hip muscle strength (ICC (3,1) 0.86 for affected hip abduction). For measurement of knee extension strength, a spring balance (ICC (3,1) 0.94 affected leg) was the most reliable. For testing balance, the Step Test (ICC (3,1) 0.94 for stepping with affected leg) and Functional Reach Test (ICC (3,1) 0.89) had the highest test-retest reliability. The ICC (3,1) values were 0.97 for walking velocity (comfortable pace) and 0.96 for the total score of the Physical Performance and Mobility Examination. CONCLUSION: The test-retest reliability of a number of simple measures of physical performance is excellent when used with this population.

Aged↗

PubMed2005

Quantitative trait loci for human muscle strength: linkage analysis of myostatin pathway genes.

This study reports the results of a multipoint linkage study that aims to unravel the genetic basis of muscle strength and muscle mass in humans. Myostatin (GDF8) is known to be a strong inhibitor of muscle growth in animals. However, studies examining human myostatin polymorphisms are rare and are limited to the GDF8 gene itself. Here, the contribution to isometric and concentric knee strength of nine key proteins involved in the myostatin pathway is studied in a nonparametric multipoint linkage analysis by means of a variance components and regression method. A sample of 367 healthy young male siblings was phenotyped on an isokinetic dynamometer and genotyped for markers of the myostatin pathway genes. Three of the loci were found significantly linked with a quantitative trait locus (QTL) for knee muscle strength. First, D13S1303 showed replication of an explorative single-point linkage study with a maximum LOD score of 2.7 (P = 0.0002). Second, maximum LOD scores of 3.4 (P = 0.00004) and 3.3 (P = 0.00005) were observed for markers D12S1042 and D12S85, respectively, at 12q12-14. Finally, marker D12S78 showed an LOD score of 2.7 at 12q22-23. We conclude that several genes involved in the myostatin pathway, but not the myostatin gene itself, are important QTLs for human muscle strength. An additional set of valuable candidate genes that were not part of the myostatin pathway was found in the chromosome 12 and 13 genomic regions.

Adolescent↗

PubMed2002

Assessment of isokinetic muscle strength in women who are obese.

STUDY DESIGN: Cross-sectional study of isokinetic trunk and knee muscle strength in women who are obese. OBJECTIVE: To provide reference values, to identify variables that affect peripheral muscle strength, and to provide recommendations for isokinetic testing of trunk and knee muscles in women who are obese and morbidly obese. BACKGROUND: The assessment of peripheral muscle strength is useful for the quantification of possible loss of strength, for exercise prescription, and for the evaluation of the effect of training programs in obese individuals. METHODS AND MEASURES: Isokinetic trunk and leg muscle strength was assessed in 241 women who were obese (18-65 years, body mass index (BMI) > or = 30 kg/m2). Trunk flexion and extension peak torque (PT) was measured using the Cybex TEF dynamometer; trunk rotation (TR) PT was measured using the Cybex TORSO dynamometer; and knee flexion/extension (KFE) PT was measured using the Cybex 350 dynamometer. Body composition was assessed using the bioelectrical impedance method; physical activity was assessed using the Baecke questionnaire; and peak VO2 was assessed using an incremental exercise capacity test on a bicycle ergometer. To identify variables related to muscle strength, Pearson correlations were computed and a stepwise multiple regression analysis was performed. RESULTS: Pearson correlation coefficients of all strength measurements at 60 degrees/s revealed low-to-moderate negative associations with age and positive associations with mass, height, fat free mass (FFM), and peak VO2 (P < 0.05), except for gravity-uncorrected trunk extension strength, which was not related to mass. The sports index of the Baecke questionnaire was associated with TR PT (r = 0.20, P < 0.01) and KFE PT (r = 0.18, P < 0.05). CONCLUSION: The weight of the trunk accounts largely for the measured trunk extensor and flexor strength in women who are obese. Contributing variables of isokinetic trunk flexion and extension strength in women who are obese are age, height, and FFM; whereas sports activities and aerobic fitness are contributing factors for trunk rotational and knee extension strength. Recommendations for measuring isokinetic muscle strength in individuals who are obese are provided.

Adult↗

PubMed1989

Strength in an elderly population.

Strengths of several upper- and lower-limb muscle groups were measured in an elderly population by using a simple, adaptable dynamometer. The bladder of a sphygmomanometer was modified by folding and surrounding it in a sewn cloth bag. It was then attached to a board for improved stability during the tests. Thirty-seven men and 81 women aged 62 to 102 years were tested. Four muscle groups were statistically determined to best represent strength-two for upper limb and two for lower limb. These strength measures were correlated with anthropometric indices, and a step-wise multiple regression was used to determine the degree of association between the variables. Men were significantly stronger than women in absolute strength, but were not different when strength was expressed relative to body weight. Within each sex, however, age was the most important variable related to loss of strength; body weight was secondary or not significant. These results suggest that age is the most important factor for relating differences in strength in an older elderly population (those aged 75 to 90 or more years). This factor must be accounted for just as body weight or cross-sectional muscle area often are, when comparing strengths in a younger population.

Aged↗

PubMed2006

Myotonic dystrophy: practical issues relating to assessment of strength.

BACKGROUND: Myotonic dystrophy type 1 is a slowly progressive multisystem disease in which skeletal muscle involvement is prominent. As novel physical and pharmacological treatments become available, it is crucial to be able to measure their efficacy accurately. METHODS: 158 consecutive patients with myotonic dystrophy were assessed annually in a specialist muscle clinic. Strength was measured using both the Medical Research Council (MRC) scale and a hand-held dynamometer. Dynamometer readings were obtained from 108 normal subjects (controls). RESULTS: The movements showing the greatest rate of change in strength were ankle dorsiflexion and pinch grip. Both of these showed a decline of only 0.06 points/year on the MRC scale. Using a hand-held dynamometer, a change in strength of 1.18 kgN/year for women and 1.61 kgN/year for men was detected. CONCLUSIONS: The MRC scale is unsuitable for detecting the small changes in strength seen in a slowly progressive disease such as myotonic dystrophy. Dynamometry provides a simple alternative that can give meaningful data over the duration of a typical clinical trial.

Adult↗

PubMed2006

The relation between ankle impairments and gait velocity and symmetry in people with stroke.

OBJECTIVE: To identify the most important factor among the ankle impairments on gait velocity and symmetry in stroke patients. DESIGN: Cross-sectional, descriptive analysis of convenience sample. SETTING: Patients from outpatient rehabilitation and neurovascular neurology departments in medical centers and municipal hospitals in Taiwan. PARTICIPANTS: Sixty-eight subjects with hemiparesis poststroke with the ability to walk independently. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Maximal isometric strength of plantarflexors and dorsiflexors were examined by a handheld dynamometer. Spasticity index, slope magnitudes between electromyographic activities, and muscle lengthening velocity of gastrocnemius during lengthening period of stance phases were measured to represent the dynamic spasticity. Passive stiffness of pantarflexors was indicated by degrees of dorsiflexion range that were less than normative values. Position error was measured by the degree of proprioceptive deficits of ankle joint by evaluating the joint position sense. Gait velocity, symmetry, and other gait parameters were measured by the GAITRite system. RESULTS: Regression analyses revealed that the dorsiflexors strength was the most important factor for gait velocity and temporal symmetry (R(2)=.30 for gait velocity, P<.001; R(2)=.36 for temporal asymmetry, P<.001). Dynamic spasticity was the most important determinant for gait spatial symmetry (R(2)=.53, P<.001). CONCLUSIONS: Gait velocity and temporal asymmetry are mainly affected by the dorsiflexors strength, whereas dynamic spasticity of plantarflexors influenced the degree of spatial gait asymmetry in our patients who were able to walk outdoors. Treatment aiming to improve different aspects of gait performance should emphasize on different ankle impairments.

Ankle↗

PubMed2006

Long-term strength training for community-dwelling people over 75: impact on muscle function, functional ability and life style.

The objective was to determine the impact of a 1-year mixed strength-training programme on muscle function, functional ability, physical activity and life style. Twice-a-week hospital-based exercise classes and a once-a-week home session were conducted. Nineteen healthy community-dwelling training (T) men (76.6 +/- 3.1 years), 19 women (77.5 +/- 4.0 years) and 20 matched controls (C) participated in this study. Training was given with a two multi-gym machines for the lower limbs (Sitting calf and Leg press, TECHNOGYM, Italy) at 60% of the repetition maximum (1 RM) and at home it was with elastic bands. The following were the measurements made: muscle function-maximum isometric strength of the knee extensors (KE) and ankle plantar flexors (PF) measured with a Cybex Norm dynamometer, leg extensor power (LEP) with the Nottingham Power Rig; functional abilities-functional reach, chair rise, bed rise, 6-min walking test, stair climbing, get up and go, one-leg standing; physical activity-aerobic activities over 3 MET intensity (AA3), intensity classes; life-style-mean daily energy expenditure (MDEE). Significant gains in muscle function and functional abilities in both training females and males were observed, but females improved significantly more than males. Males (T + C) showed higher AA3 times than females (T + C) (P = 0.02), with females significantly more involved in light-intensity activities. We observed a 60% increase (t = 2.45) in AA3 time in T, but no increase in C. Trained males increased Class 2 physical activity time by 146% (t = 2.82) and trained females by 16% (t = 2.23). MDEE increased by 10% (t=2.62) in trained males. Our long-term mixed programme can improve muscle function and functional abilities in elderly females and functional abilities in males. It can positively affect the amount of habitual physical activity and the life-style of males and females over 75.

Activities of Daily Living↗

PubMed2004

Muscle strength in obese elderly women: effect of recreational physical activity in a cross-sectional study.

BACKGROUND: Muscle strength (MS) may be impaired in obese persons, and this impairment may be a consequence of both obesity and low physical fitness. OBJECTIVE: We investigated whether MS differed between obese [body mass index (BMI; in kg/m2 > 29], normal-weight (BMI = 24-29), and lean (BMI < 24) elderly subjects and compared the MS of sedentary and active subjects according to their BMI group. DESIGN: The study included 215 obese [ (+/- SD) age: 80.0 +/- 3.5 y; BMI: 31.9 +/- 2.6], 630 normal-weight (age: 80.2 +/- 3.7 y; BMI: 26.3 +/- 1.4), and 598 lean (age: 80.7 +/- 3.5 y; BMI: 21.6 +/- 1.8) women with good functional ability. A cross-sectional design was used. Anthropometric measures (weight, height); measures of appendicular skeletal muscle mass (by dual-energy X-ray absorptiometry), isometric knee and elbow extension (by statergometer), and isometric handgrip strength (by dynamometer); and data on health status and self-reported recreational physical activity (RPA: walking, gymnastics, cycling, swimming, gardening) were collected. RESULTS: Absolute (unadjusted) MS was higher in obese than in lean women (P < 0.01), except for handgrip strength (P > 0.05). When adjusted for age, height, RPA, pain, depression, and appendicular skeletal muscle mass, MS did not differ significantly between obese, normal-weight, and lean subjects, except for knee extension (significant interaction effect with RPA; P = 0.01). With increasing BMI, lower limb strength did not change in the sedentary women but increased in active (> or = 1 h/wk in > or = 1 RPA for > or = 1 mo) women. All adjusted MS measures in active participants were significantly higher (P < 0.001) than those in their sedentary peers. CONCLUSION: The adjusted MS of elderly women is not associated with obesity but is higher in active subjects than in sedentary ones, especially in the lower limbs of obese subjects.

Aged↗

PubMed1983

Assessment of abdominal and back extensor function. A quantitative approach and results for chronic low-back patients.

A method was developed to obtain static and dynamic measures of trunk flexor and extensor strength and endurance. The method was evaluated using 32 normal subjects. Variables of trunk strength and endurance were used to compare 24 normals (12 men and 12 women) and 24 patients (16 men and eight women) with chronic low-back dysfunction. The Iowa Trunk Dynamometer is acceptably reliable and provides for assessment of isolated function of the abdominal and back muscles. For peak abdominal and back extensor strength, the range of superiority of men over women was 39-57%, and the range of superiority of normals over patients with chronic low-back dysfunction was 48-82%. Using time to percent decrement of peak strength as a criterion, the abdominals were more susceptible to fatigue than the back extensors, women demonstrated more endurance than men, and the endurance for normals was less than those patients who were able to perform dynamic reciprocal trunk movements.

Abdominal Muscles↗

PubMed2004

Effect of training on the muscle strength and dynamic balance ability of adults with down syndrome.

The purpose of this study was to evaluate the effect of training on the muscle strength and dynamic balance ability of adults with Down syndrome (DS). Twenty-five adults with DS were separated into 2 groups. Fifteen subjects (mean age, 24.5 years) constituted the experiment group, whereas 10 subjects (mean age, 24.7 years) were in the control group of the study. Parameters measured were peak torque, isokinetic muscle endurance, and dynamic balance ability. All subjects performed a leg strength test on a Cyber II isokinetic dynamometer. In addition, the subjects' dynamic balance ability was measured by means of a balance deck (Lafayette). The experimental group followed a 12-week training program. As the results indicated, the experimental group showed a statistically significant improvement in all measured values when compared with the control group. It is concluded that adults with DS can improve their physical and kinetic abilities with the application of a systematic and well-designed training program.

Adult↗

PubMed1994

Assessment of quadriceps muscle performance by a hand-held dynamometer and an isokinetic dynamometer.

Assessment of muscle performance is an integral component of patient evaluation. The primary purposes of this study were to examine the relationship between isokinetic dynamometer isokinetic peak force values and hand-held dynamometer isometric peak force values when assessing quadriceps muscle performance in subjects with orthopaedic knee dysfunctions (N = 21) and to test for differences in muscle performance between injured and noninjured lower extremities using a hand-held dynamometer and an isokinetic dynamometer. An analysis of variance was used to compare injured and noninjured extremities for both testing devices. A Pearson product moment correlation was used to examine the relationship between the hand-held dynamometer and isokinetic dynamometer values. No significant difference between extremities at 0 degrees (p = 0.1224) or 60 degrees (p = 0.8267) was revealed when testing with the hand-held dynamometer. The isokinetic dynamometer, however, revealed a significant difference between extremities at 60 degrees/sec (p = 0.0041). Correlations between the two devices were significant, ranging from r = 0.57 to 0.80. We concluded that these correlations were misleading because more force was generated by the quadriceps muscles tested than a tester of average strength could resist. Further research is needed to validate the use of the hand-held dynamometer by a tester of average strength.

Adolescent↗

PubMed2006

Anthropometric and physiological characteristics of junior elite volleyball players.

OBJECTIVES: To investigate the anthropometric and physiological characteristics of junior elite volleyball players. METHOD: Twenty five national level volleyball players (mean (SD) age 17.5 (0.5) years) were assessed on a number of physiological and anthropometric variables. Somatotype was assessed using the Heath-Carter method, body composition (% body fat, % muscle mass) was assessed using surface anthropometry, leg strength was assessed using a leg and back dynamometer, low back and hamstring flexibility was assessed using the sit and reach test, and the vertical jump was used as a measure of lower body power. Maximal oxygen uptake was predicted using the 20 m multistage fitness test. RESULTS: Setters were more ectomorphic (p<0.05) and less mesomorphic (p<0.01) than centres. Mean (SD) of somatotype (endomorphy, mesomorphy, ectomorphy) for setters and centres was 2.6 (0.9), 1.9 (1.1), 5.3 (1.2) and 2.2 (0.8), 3.9 (1.1), 3.6 (0.7) respectively. Hitters had significantly greater low back and hamstring flexibility than opposites. Mean (SD) for sit and reach was 19.3 (8.3) cm for opposites and 37 (10.7) cm for hitters. There were no other significant differences in physiological and anthropometric variables across playing positions (all p>0.05). CONCLUSION: Setters tend to be endomorphic ectomorphs, hitters and opposites tend to be balanced ectomorphs, whereas centres tend to be ectomorphic mesomorphs. These results indicate the need for sports scientists and conditioning professionals to take the body type of volleyball players into account when designing individualised position specific training programmes.

Adolescent↗

PubMed1986

Influence of subtypes of fast-twitch fibers on isokinetic strength in untrained men.

The purpose of the present study was to investigate the influence of the subtypes of fast-twitch (FT) fibers on the peak torque per unit cross-sectional area in working muscle. Muscle biopsies were taken from the right vastus lateralis of nine healthy untrained men. Using staining for myofibrillar ATPase after preincubation at pH 4.3 and 4.6, muscle fibers were classified as slow-twitch (ST), FTa, and FTb. Cross-sectional area of the leg extensor muscles was measured by ultrasonic method. Maximum voluntary strength for the leg extensor muscles was determined as peak torques with constant angular velocity using an isokinetic dynamometer. The peak torques at various angular velocities (30, 60, 120, and 180 degrees/s) indicated statistically significant positive correlations to the percent number and area of FTa fibers in m. vastus lateralis. Other fiber types, such as ST or FTb, however, were not correlated significantly to the peak torques at all angular velocities. A significant positive correlation of 0.766 (180 deg/s) was observed between peak torque per unit cross-sectional area of the leg extensor muscle and the percent number of FTa fibers. These results suggest that in untrained men, the percent number of FTa fibers plays a more important role in producing high peak torques than the percent number of FTb and ST and that even if muscle cross-sectional area is equal, a muscle with a high percent number of FTa fibers can exert higher isokinetic strength.

Adolescent↗

PubMed1993

A comparison of hand-held isometric strength measurement with isokinetic muscle strength measurement in the elderly.

OBJECTIVE: To compare hand-held isometric muscle strength measurement to an isokinetic muscle strength measurement in a healthy elderly population. DESIGN: Cross-sectional survey. SETTING: Retirement community in Southeastern Arizona. PARTICIPANTS: Thirty-two volunteers (16 men and 16 women) age 60 and over (mean age 70.3 years) who were free of musculoskeletal problems and did not have significant health problems. INTERVENTIONS: None. MEASUREMENTS: Isometric muscle strength was determined using a hand-held isometric strength device (Penny and Giles) for elbow flexion and extension and knee flexion and extension. Isokinetic muscle strength (average peak torque and average work per repetition) was measured on the same individuals using a Lido isokinetic dynamometer. RESULTS: Correlations between the strength measurement techniques were generally favorable with the lowest correlation being .72, (95 percent confidence interval .50-.86) and the highest being .85, (95 percent confidence interval .72-.93). However, there was substantial variability of hand-held strength reading at some levels of isokinetic strength. CONCLUSIONS: Hand-held dynamometry for strength measurement correlates strongly with measurement of strength using isokinetic dynamometry. Despite these high correlations, there is remaining variability of hand-held muscle strength readings when compared with isokinetic strength measurement at some levels of isokinetic muscle strength. Modification of the testing methodology or instrumentation used in this study is needed to improve the consistency of these measurements.

Aged↗

PubMed2001

Quadriceps and hamstring strength changes as a function of selective dorsal rhizotomy surgery and rehabilitation.

PURPOSE: Objective measures of strength in children with cerebral palsy (CP) are needed to determine the effect that selective dorsal rhizotomy surgery (SDR) and subsequent rehabilitation have on muscle strength. This investigation quantified quadriceps and hamstring strength in children with CP pre-SDR and eight months post-SDR. METHOD: Nineteen children with CP and 20 children without disabilities (WD group) were tested with an isokinetic dynamometer. The children performed a maximum concentric contraction of the quadriceps muscles as the dynamometer moved the knee from a flexed position to an extended position at 10 degrees per second. A maximum concentric contraction of the hamstring muscles was then performed as the knee was moved from extension to flexion. Four variables were recorded from the torque-angle data; peak extension and flexion torque and extension and flexion work. RESULTS: Children with CP, both pre- and post-SDR were significantly weaker in all strength measures compared with the WD group. Children with CP post-SDR and rehabilitation had significantly greater peak torque and work values compared with their pre-SDR values. The results agreed with previous studies indicating that children with CP are weaker than their peers without disabilities. Previous studies on strength changes after SDR remain controversial. CONCLUSIONS: The results of this study showed a significant increase in strength at the knee after rhizotomy and rehabilitation.

Journal Article↗

PubMed1994

Donor leg morbidity after pedicled rectus femoris muscle flap transfer for abdominal wall and pelvic reconstruction.

The pedicled rectus femoris muscle and myocutaneous flap has found application for a variety of soft tissue defects of the groin, pelvis, and lower abdomen. Although a number of authors have discussed the usefulness of this muscle flap, few have documented the morbidity from loss of this muscle in the leg. We have studied 7 patients who underwent unilateral rectus femoris muscle transfer, comparing strength of the donor knee to the normal knee. All patients were studied using a computerized dynamometer for strength of knee flexion and contraction. We found that loss of the rectus femoris in patients not undergoing a postoperative program of therapy led to an average decrease in strength about the knee of 24% to 28%, depending on the motion measured. A single patient who underwent an intensive postoperative therapy program had return of normal strength in his donor leg. Despite this common loss of strength, patient complaints were few and the results of reconstruction appeared to outweigh this loss of strength.

Abdominal Muscles↗

PubMed2005

Muscle mass, muscle strength, and muscle fat infiltration as predictors of incident mobility limitations in well-functioning older persons.

BACKGROUND: Lower muscle mass has been correlated with poor physical function; however, no studies have examined this relationship prospectively. This study aims to investigate whether low muscle mass, low muscle strength, and greater fat infiltration into the muscle predict incident mobility limitation. METHODS: Our study cohort included 3075 well-functioning black and white men and women aged 70-79 years participating in the Health, Aging, and Body Composition study. Participants were followed for 2.5 years. Muscle cross-sectional area and muscle tissue attenuation (a measure of fat infiltration) were measured by computed tomography at the mid-thigh, and knee extensor strength by using a KinCom dynamometer. Incident mobility limitation was defined as two consecutive self-reports of any difficulty walking one-quarter mile or climbing 10 steps. RESULTS: Mobility limitations were developed by 22.3% of the men and by 31.8% of the women. Cox's proportional hazards models, adjusting for demographic, lifestyle, and health factors, showed a hazard ratio of 1.90 [95% confidence interval (CI), 1.27-2.84] in men and 1.68 (95% CI, 1.23-2.31) in women for the lowest compared to the highest quartile of muscle area (p <.01 for trend). Results for muscle strength were 2.02 (95% CI, 1.39-2.94) and 1.91 (95% CI, 1.41-2.58), p <.001 trend, and for muscle attenuation were 1.91 (95% CI, 1.31-2.83) and 1.68 (95% CI, 1.20-2.35), p <.01 for trend. When included in one model, only muscle attenuation and muscle strength independently predicted mobility limitation (p < .05). Among men and women, associations were similar for blacks and whites. CONCLUSION: Lower muscle mass (smaller cross-sectional thigh muscle area), greater fat infiltration into the muscle, and lower knee extensor muscle strength are associated with increased risk of mobility loss in older men and women. The association between low muscle mass and functional decline seems to be a function of underlying muscle strength.

Aged↗

PubMed1990

Skeletal muscle fiber area alterations in two opposing modes of resistance-exercise training in the same individual.

The purpose of this study was to observe fiber area changes that might occur in the same subject from two opposing resistance-exercise training regimes isolating the quadriceps muscle group. Twelve college-age men divided into two groups participated in each of two 7.5-week regimens; one performed a muscular strength program (high-resistance, low-repetition) 4 days a week on a resistance-exercise apparatus, while the other performed a muscular endurance (low-resistance, high-repetition) program. After a 5.5-week hiatus, the groups changed regimens for the second 7.5 weeks. Closed-needle biopsies of the dominant vastus lateralis and isokinetic dynamometer evaluations were made before and at the end of each training period. The muscle samples were analyzed for area changes. In both groups the initial exercise stimulus, whether for strength or endurance, increased the area of fibers of all three major types (I, IIA, and IIB). Subjects doing strength exercises as their second treatment showed a further increase in the area of type I and IIB fibers, whereas those doing endurance exercises showed a decrease in all fiber types. From the first to the last biopsy all fiber areas were decreased (P less than 0.05) in the control-strength-endurance group and increased (P less than 0.05) in the control-endurance-strength group. These results suggested that endurance exercise preceding strength exercise in an isolated muscle group maximized fiber area adaptations to exercise stress. Consideration should thus be given in exercise and rehabilitation programs to the muscle cellular adaptations evidenced in different orders of training, particularly if muscular strength is considered important.

Adenosine Triphosphatases↗