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Results for “Muscle Strength Dynamometer”

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PubMed2000

Handgrip strength is an independent predictor of distal radius bone mineral density in postmenopausal women.

Several cross-sectional studies have reported a positive correlation between muscle strength and local bone mineral density. However, very few studies have evaluated the possible role of confounding variables, which may be substantial as both bone mineral density and muscle strength are multifactorial variables. We studied 140 postmenopausal women who underwent their first osteodensitometry in our hospital. Of these, 102 women affected neither by bone diseases apart from primary osteoporosis nor treated with drugs affecting bone mass were selected. Distal radius bone mineral density of the non-dominant arm was assessed by dual photon absorptiometry. Handgrip strength was measured by a handheld dynamometer. The following factors influencing bone mass were also considered: age, years since menopause, years of cyclic ovarian activity, body weight, body height, body mass index, and both calcium and alcohol dietary intake. Statistical evaluation was performed by stepwise multiple regression analysis. This showed that only two variables were independently related to bone mineral density: handgrip strength (which was the best bone density predictor among the studied independent variables) and years since menopause. R2 value was 0.43 (F=38.04, p < 0.001). All the other variables studied were not significantly related to bone density when the effects of both strength and years since menopause were considered. In conclusion, the data showed that handgrip strength was a strong independent predictor of distal radius bone mineral density in postmenopausal women. Clinical assessment of osteoporosis risk factors, including muscle strength, is recommended: although it is not an adequate substitute for bone densitometry, it can help clinicians to identify the risk groups at which to direct bone density measurement.

Adult↗

PubMed2006

Percentile values of isokinetic peak torque in children six through thirteen years old.

PURPOSE: The purpose of this study was to standardize an isokinetic testing protocol for quadriceps and hamstrings in children who are typically developing and are six through 13 years of age, to establish percentile charts of isokinetic peak torque strength for quadriceps and hamstrings by gender and age, and to determine the best predictors of strength for each of three testing speeds. METHODS: A total of 3587 children were tested for isokinetic knee strength according to our protocol on Biodex System II and III isokinetic dynamometers. Therapists participating in the study were trained on the protocol and inter-rater reliability was established. Both dominant and nondominant legs were tested at three speeds. Data were collected on peak torque, time to peak torque, and agonist/antagonist ratio. Data were also gathered on maturation level, gender, height, weight, leg length, laterality, and activity level to allow for investigation of correlations with peak torque. All data were entered in an Excel spreadsheet. RESULTS: Percentile charts of normal isokinetic muscle strength were generated using SPSS 12.0 for each age and gender at three speeds (60, 120, and 180 degrees per second). Stepwise regression analysis determined height to be the best predictor of peak torque for both quadriceps and hamstrings at all speeds. CONCLUSIONS: This study is the first to report normative peak torque values for quadriceps and hamstrings in children. By using a standardized testing protocol and normative data, clinicians will be able to assess the degree of muscle weakness as well as the effectiveness of intervention strategies.

Adolescent↗

PubMed2005

What change in isokinetic knee muscle strength can be detected in men and women with hemiparesis after stroke?

OBJECTIVE: To assess the intra-rater (between occasions) test-retest reliability of isokinetic knee muscle strength measurements in subjects with chronic poststroke hemiparesis and to define limits for the smallest change that indicates real (clinical) improvements for stroke patients. SUBJECTS: Fifty men and women (mean age 58 +/- 6.4 years) 6-46 months post stroke, able to walk at least 300 m with or without a unilateral assistive device. METHODS: Maximal concentric knee extension and flexion contractions at 60 degrees/s and 120 degrees/s, and maximal eccentric knee extension contractions at 60 degrees/s, with the paretic and nonparetic limbs, were performed seven days apart using a Biodex dynamometer. MEASURES: Reliability of the maximum peak torque measurements was evaluated with the intraclass correlation coefficient (ICC(2,1)), the Bland and Altman analyses, the standard error of measurement (SEM and SEM%) and the smallest real difference (SRD and SRD%). RESULTS: Test-retest agreements were high (ICC(2,1) 0.89-0.96) with no discernible systematic differences between limbs, angular velocities and modes. The SEM%, representing the smallest change that indicates a real (clinical) improvement for a group of subjects, was relatively small (8-20%). The SRD%, representing the smallest change that indicates a real improvement for a single subject ranged from 26% to 33% for concentric knee extension, from 39% to 55% for concentric knee flexion, and from 22% to 25% for eccentric knee extension. CONCLUSION: Isokinetic knee muscle strength can be reliably measured and used to detect real improvements following an intervention for single subjects as well as for groups of subjects with chronic mild to moderate hemiparesis after stroke.

Aged↗

PubMed1998

Isokinetic strength testing does not predict hamstring injury in Australian Rules footballers.

OBJECTIVE: To determine the relation of hamstring and quadriceps muscle strength and imbalance to hamstring injury using a prospective observational cohort study METHOD: A total of 102 senior male Australian Rules footballers aged 22.2 (3.6) years were tested at the start of a football season. Maximum voluntary concentric and eccentric torque of the hamstring and quadriceps muscles of both legs was assessed using a Kin-Com isokinetic dynamometer at angular velocities of 60 and 180 degrees/second. Twelve (11.8%) players sustained clinically diagnosed hamstring strains which caused them to miss one or more matches over the ensuing season. RESULTS: There were no significant differences for any of the isokinetic variables comparing the injured and non-injured legs in players with unilateral hamstring strains (n=9). Neither the injured nor the non-injured leg of injured players differed from the mean of left and right legs in non-injured players for any isokinetic variable. The hamstring to opposite hamstring ratios also did not differ between injured and non-injured players. A hamstring to opposite hamstring ratio of less than 0.90 and a hamstring to quadriceps ratio of less than 0.60 were not associated with an increased risk of hamstring injury. A significantly greater percentage of players who sustained a hamstring strain reported a history of hamstring strain compared with non-injured players (p=0.02). However, this was not related to muscle weakness or imbalance. CONCLUSIONS: Isokinetic muscle strength testing was not able to directly discriminate Australian Rules football players at risk for a hamstring injury.

Adult↗

PubMed2004

Determinants of lower-body muscle power in early postmenopausal women.

OBJECTIVES: To investigate the association between muscle size, density, and fiber composition; body composition; maximal isometric knee extension strength (KES); and lower-body muscle power in healthy postmenopausal women. DESIGN: Cross-sectional analysis of baseline data from a 1-year randomized controlled experiment. SETTING: University-based research laboratory. PARTICIPANTS: Seventy-eight healthy postmenopausal women aged 50 to 57. MEASUREMENTS: Maximal lower-body muscle power was assessed using vertical jump height (VJH). Maximal isometric KES was measured on a dynamometer chair. Computed tomography scans were used to determine lean-tissue cross-sectional area and density of the thigh and lower leg muscles. Relative area occupied by type I, IIa, IIax, and IIx muscle fibers was assessed from the vastus lateralis muscle. lean body mass and total body fat mass were assessed using bioelectrical impedance. RESULTS: High VJH was associated with low body fat mass, high KES, and high density of thigh and lower leg muscles. Multivariate linear regression modeling revealed that high thigh muscle density (beta=0.242; P=.019), relative area occupied by the fastest muscle fiber types (IIax+IIx; beta=0.246; P=.007), KES (beta=0.247; P=.007), and low body fat mass (beta=-0.455; P<.001) were independently associated with high VJH, accounting for 45% of the variability in VJH. CONCLUSION: This study showed that thigh muscle composition, muscle strength, and body fat mass are important determinants of lower-body muscle power production during weight-bearing activity in healthy postmenopausal women.

Aged↗

PubMed1997

Bone mass in female volleyball players: a comparison of total and regional bone mass in female volleyball players and nonactive females.

The purpose of this cross-sectional study was to evaluate bone mass in female athletes participating in an impact loading sport (volleyball), and especially to investigate whether any changes in bone mass might be related to the type and magnitude of weightbearing loading and muscle strength. The volleyball group consisted of 13 first division players (age 20.9 +/- 3.7 years) training for about 8 hours/week, and the reference group consisted of 13 nonactive females (age 25.0 +/- 2.4 years) not participating in any kind of regular or organized sport activity. The groups were matched according to weight and height. Areal bone mineral density (BMD) was measured in total body, head, lumbar spine, femoral neck, Ward's triangle, trochanter, the whole femur, and humerus using dual-energy-X-ray absorptiometry. Isokinetic concentric peak torque of the quadricep and hamstring muscles was measured using an isokinetic dynamometer. Compared with the controls, the volleyball players had a significantly (P < 0.05-0.01) higher BMD of the total body (6.1%), lumbar spine (13.2%), femoral neck (15.8%), Ward's triangle (17.9%), trochanter (18.8%), nondominant femur (8.2%), and humerus (dominant 9.5%, nondominant 10.0%), but not of the head and the dominant whole femur. The dominant humerus showed significantly higher BMD than the nondominant humerus in both the volleyball and nonactive group (P < 0.05). There was no significant difference in muscle strength of the thigh between the two groups. In the nonactive group, muscle strength in the quadriceps, and especially hamstrings, was correlated to BMD of the adjacent bones (whole femur, hip sites) and also to distant sites (humerus). However, in the volleyball group there were no correlations between muscle strength and BMD of the adjacent bones, but quadricep strength correlated to BMD of the humerus. These results clearly show that young female volleyball players have a high bone mass. The demonstrated high bone mass seems to be related to the type of loading subjected to each BMD site. Muscle strength of the thigh seems to have little impact on BMD in female volleyball players.

Absorptiometry, Photon↗

PubMed1998

Back extensor and psoas muscle cross-sectional area, prior physical training, and trunk muscle strength--a longitudinal study in adolescent girls.

The association between physical training, low back extensor (erector spinae plus multifidus muscles) and psoas muscle cross-sectional areas (CSA) and strength characteristics of trunk extension and flexion were studied in adolescent girls. A group of athletes (n = 49) (age range 13.7-16.3 years) consisting of gymnasts, figure skaters and ballet dancers was age-matched with non-athletes (n = 17) who acted as a sedentary control group. The CSA of psoas muscles and multifidus plus erector spinae muscles were measured from lumbar axial images by magnetic resonance imaging. Maximal trunk extension and flexion forces were measured in a standing position using a dynamometer and trunk musculature endurance was evaluated using static holding tests. When CSA were adjusted with body mass, the athletes showed significantly greater CSA in both muscles studied (psoas P < 0.001; erector spinae plus multifidus P < 0.05) than the non-athletes. The athletes also had a greater absolute psoas muscle CSA (P < 0.01) and trunk flexion force (P < 0.01) compared to the controls. When the forces were expressed relative to body mass, the athletes were superior both in trunk flexion (P < 0.001) and extension (P < 0.001). There was a significant correlation between muscle CSA and strength parameters, but the force per muscle CSA did not differ significantly between the athletes and the non-athletes. In addition, the athletes showed a better body mass adjusted muscle endurance in trunk flexion (P < 0.05) than the non-athletes. Our study indicated that regular physical training enhances trunk musculature hypertrophy, force and endurance in adolescent girls, and that there is an association between muscle CSA and strength parameters.

Adolescent↗

PubMed1984

Effects of an aquatic fitness program on the muscular strength and endurance of patients with multiple sclerosis.

This study quantified the effects of an aquatic exercise program on muscular strength, endurance, work, and power of patients with multiple sclerosis. Ten individuals with a mean age of 40 years participated in a 10-week aquatic exercise program. Two types of isokinetic dynamometers were used to assess the muscular variables studied. A Cybex II dynamometer was used to measure peak torque, work, and fatigue in the knee flexor and extensor muscles and a biokinetic swim bench was used to measure muscular force, work, fatigue, and power in the upper extremities. Five velocity settings were selected for each of three testing trials (pretrial, midtrial, and posttrial). For the lower extremities, analysis of variance indicated a significant improvement of peak torque for knee extensor muscles from the pretrial to midtrial (p less than .05). Peak torque values from pretrial to midtrial for knee flexors and from midtrial to posttrial for both the knee extensor and flexor muscles indicated a nonsignificant difference at each velocity studied. Fatigue and work values in the lower extremities improved significantly between the pretrial and posttrial (p less than .05). For the upper extremities, an analysis of variance indicated a significant increase in all force measurements from pretrial to posttrial (p less than .05). Power and total work values also improved significantly (p less than .05). No significant difference in fatigue measurements for the upper extremities was found. The results of this investigation indicated that an aquatic exercise program may induce positive changes in muscular strength, fatigue, work, and power in patients with multiple sclerosis.

Adult↗

PubMed2004

The effect of creatine supplementation on strength recovery after anterior cruciate ligament (ACL) reconstruction: a randomized, placebo-controlled, double-blind trial.

BACKGROUND: Creatine supplementation has been shown to augment training-induced strength gains. The purpose of this study was to examine the effect of creatine supplementation on recovery of muscle strength after anterior cruciate ligament (ACL) reconstruction. HYPOTHESIS: Creatine supplementation will facilitate strength gains after ACL reconstruction. STUDY DESIGN: Double-blind, prospective, and randomized clinical trial. METHODS: Sixty patients were randomized into creatine or placebo groups. Quadriceps and hamstring strength and power were measured isokinetically. Hip flexor, abductor, and adductor strengths were measured with a handheld dynamometer prior to surgery and at 6 weeks, 12 weeks, or 6 months after surgery. RESULTS: From 6 weeks to 12 weeks after surgery, there were significant increases in strength on the involved side for knee extension (47%), knee flexion (27%), hip flexion (20%), hip abduction (9%), and hip adduction (17%). These strength improvements were unaffected by creatine supplementation with similar effects in the creatine and placebo groups. From 6 weeks to 12 weeks after surgery, there were significant increases in power on the involved side for knee extension (46%) and knee flexion (26%), but these effects were not affected by creatine supplementation. At 6 months, creatine supplementation did not affect outcome as measured by the single leg hop test for distance or the knee outcome score. CONCLUSIONS: The results demonstrate that patients do not benefit from creatine supplementation during the first 12 weeks of rehabilitation after ACL reconstruction.

Administration, Oral↗

PubMed2006

Isometric muscle torque in children 5 to 15 years of age: normative data.

OBJECTIVE: To establish reference values of arm and leg muscle strength as measured by isometric torque production in healthy children. DESIGN: Measurement of isometric muscle strength in healthy children. SETTING: Public school. PARTICIPANTS: Healthy children (N=149; 76 boys, 73 girls) ages 5 to 15 years. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Isometric torque values of 12 arm and leg muscle groups of healthy children as measured by a handheld dynamometer. RESULTS: Normative data were obtained for children 5 to 15 years of age. There was an increase in torque with age and weight and a strong correlation with both age and weight. There were few differences between boys and girls. Equations for predicted torque taking into account age, weight, and sex were calculated. The agreement between examiners was excellent. CONCLUSIONS: Studies on growing children require comparison to healthy (normal) children to assess the amount of deviation from normal and to be able to draw conclusions of change over time. The reference values for torque in combination with a predicted value based on the child's age, weight, and sex make it possible to compare over time and between subjects and provide a tool for evaluation of physical status and efficacy of therapy.

Adolescent↗

PubMed2005

The development and validation of equations to predict grip force in the workplace: contributions of muscle activity and posture.

The inherent difficulty of measuring forces on the hand in ergonomic workplace assessments has led to the need for equations to predict grip force. A family of equations was developed, and validated, for the prediction of grip force using forearm electromyography (six finger and wrist muscles) as well as posture of the wrist (flexed, neutral and extended) and forearm (pronated, neutral, supinated). Inclusion of muscle activity was necessary to explain over 85% of the grip force variance and was further improved with wrist posture but not forearm posture. Posture itself had little predictive power without muscle activity (<1%). Nominal wrist posture improved predictive power more than the measured wrist angle. Inclusion of baseline muscle activity, the activity required to simply hold the grip dynamometer, greatly improved grip force predictions, especially at low force levels. While the complete model using six muscles and posture was the most accurate, the detailed validation and error analysis revealed that equations based on fewer components often resulted in a negligible reduction in predictive strength. Error was typically less than 10% under 50% of maximal grip force and around 15% over 50% of maximal grip force. This study presents detailed error analyses to both improve upon previous studies and to allow an educated decision to be made on which muscles to monitor depending on expected force levels, costs and error deemed acceptable by the potential user.

Ergonomics↗

PubMed2002

Relation of estrogen receptor-alpha gene polymorphism and hormone replacement therapy to fall risk and muscle strength in early postmenopausal women.

BACKGROUND: Several factors may increase fracture risk, among them reduced bone mineral density (BMD), increased bone resorption, microarchitectural deterioration of bone, increased fall risk, and decreased muscle strength. We have previously reported that PvuII polymorphism of the estrogen receptor-alpha (ER alpha) gene is associated with bone loss rate, fracture risk, and response to hormone replacement therapy (HRT) in early postmenopausal Finnish women. METHOD: We studied the influence of the ER alpha genotype on fall risk and muscle strength in a 5-year randomized HRT trial of 331 early postmenopausal women (subgroup of the population-based OSTPRE study, Kuopio, Finland). A 5-year postal inquiry in May 1994 included questions on falls during the previous 12 months. Grip strength was measured with dynamometer. The ER alpha gene polymorphism was analysed using PCR and PvuII restriction enzyme digestion. RESULTS. In all, 97 out of the 331 women reported falls. Half of those (56%) were slip falls, mostly during the winter season. In the HRT group, the ER alpha genotype was associated with fall risk (P = 0.002, logistic regression). The risk of falls (RR) was higher in women with the PP genotype than in those with the Pp (RR = 5.26, 95% CI 1.98-13.94, P = 0.001) or the pp (RR = 3.84, 95% CI 1.46-10.12, P = 0.007) genotype. When the falls were divided into slip (environment-related) and non-slip (endogenous) falls, the non-slip falls were associated with the genotype (P = 0.004), but the slip falls were not so clearly (P = 0.061). When all falls and non-slip falls were adjusted to the number of chronic health disorders and the variable time-since-menopause, the difference between the genotypes persisted (P = 0.003 and P = 0.010, respectively). In the non-HRT group, the ER alpha genotype was not associated with fall risk. The baseline or the 5-year grip strength values were not influenced by the ER alpha genotype. In conclusion, ER alpha polymorphism is associated with fall risk, especially with non-slip falls, in early postmenopausal Finnish women during the HRT. We have previously reported that, during HRT, women with the P allele have decreased fracture risk and that they may preferentially derive benefit from the positive effect of HRT on BMD. This suggests that the influence of ER alpha polymorphism may depend on the target tissue (bone versus the nervous system). CONCLUSIONS: In these early postmenopausal, non-osteoporotic and relatively healthy women, the increased fall risk associated with the PP genotype was not associated with increased fracture risk, possibly due to improved bone strength during the HRT although falls generally predispose to fractures.

Accidental Falls↗

PubMed1985

Thigh muscle mass and function in patients treated with glucocorticoids.

Treatment with glucocorticoids causes wasting of proximal skeletal muscles. There is evidence that physical training improves muscle mass and strength in glucocorticoid-treated rats. Whether this is also true in humans is unknown. The present investigation was designed to establish in what respect moderate physical training may alter muscle mass and function as assessed quantitatively by computed tomography (CT) and with an isokinetic dynamometer (Cybex II). Compared with matched controls, both female (n = 17) and male (n = 22) patients treated with prednisone (15.4 +/- 6.6 mg die-1) had a lower mid-thigh muscle area of 20 and 45% and an increased mid-thigh fat/muscle ratio of 25 and 100%, respectively. The mean peak torque and the total work output of the thigh muscle were lower by 20-30% (n = 14). Fifty days of isokinetic training in six patients increased the thigh muscle area, decreased the thigh fat area and normalized the mean peak torque and total work output. Thus, glucocorticoid-induced muscle wasting can be reversed by increasing physical activity.

Adult↗

PubMedDate not supplied

The abductor and adductor strength characteristics of professional baseball pitcherse.

The purpose of this investigation was to establish a data base regarding the isokinetic muscular performance characteristics of the abductor and adductor muscles of professional baseball pitchers. Eighty-three healthy professional baseball pitchers (mean age, 22.6 years; mean weight, 199 pounds) were evaluated by use of a Biodex isokinetic dynamometer. Isokinetic tests were performed concentrically at 180 and 300 deg/sec for both the throwing and nonthrowing shoulders. The testing protocol and test repetitions were standardized for each subject. Statistical analysis was performed using a paired t-test. Determination of the correlation coefficient was made at the P < 0.05 level of significance. Test results for bilateral comparisons of mean peak torque for the throwing and nonthrowing shoulders demonstrated a significant difference in adductor values between the dominant and nondominant shoulders at both test speeds. There were no significant differences between extremities for the shoulder abductor muscles. The abductor-to-adductor muscle ratios between the throwing and nonthrowing shoulders were also statistically significant at both test speeds. Throwing arm values were 82.5% at 180 deg/sec and 93.8% at 300 deg/sec compared with only 66.0% and 70.3%, respectively, for the nonthrowing shoulders.

Acceleration↗

PubMed1985

Evidence that prednisone-induced myopathy is reversed by physical training.

Treatment with glucocorticoids causes wasting of proximal skeletal muscles. There is evidence that physical training improves muscle mass and strength in glucocorticoid-treated rats. Whether this is also true in humans is not known. The present investigation was designed to establish in what respect moderate physical training may alter muscle mass and function as assessed quantitatively by computed tomography (CT) and an isokinetic dynamometer (Cybex II). Compared with matched normal subjects (n = 12), patients (n = 12) treated with prednisone [12.6 +/- 3.3 (+/- SD) mg/day] had a 20% lower midthigh muscle area and a 36% increase in midthigh fat to muscle ratio. The mean peak torque and the total work output of the thigh muscle were lower by more than 20%. Baseline measurements of total work output or peak torque at all tested velocities increased with midthigh muscle area (r = 0.73; n = 24; P less than 0.001). Fifty days of isokinetic training in 12 patients increased the thigh muscle area, decreased the thigh fat area, and normalized the mean peak torque and total work output. The increase in peak torque was inversely correlated with the daily dose of prednisone (r = 0.60; n = 12; P less than 0.05). Thus, glucocorticoid-induced muscle wasting can be reversed by increasing physical activity in patients taking a low to moderate dose of prednisone.

Adult↗

PubMed2001

Influence of compression therapy on symptoms following soft tissue injury from maximal eccentric exercise.

STUDY DESIGN: A between groups design was used to compare recovery following eccentric muscle damage under 2 experimental conditions. OBJECTIVE: To determine if a compression sleeve donned immediately after maximal eccentric exercise would enhance recovery of physical function and decrease symptoms of soreness. BACKGROUND: Prior investigations using ice, intermittent compression, or exercise have not shown efficacy in relieving symptoms of delayed onset muscle soreness (DOMS). To date, no study has shown the effect of continuous compression on DOMS, yet this would offer a low cost intervention for patients suffering with the symptoms of DOMS. METHODS AND MEASURES: Twenty nonimpaired non-strength-trained women participated in the study. Subjects were matched for age, anthropometric data, and one repetition maximum concentric arm curl strength and then randomly placed into a control group (n = 10) or an experimental compression sleeve group (n = 10). Subjects were instructed to avoid pain-relieving modalities (eg, analgesic medications, ice) throughout the study. The experimental group wore a compressive sleeve garment for 5 days following eccentric exercise. Subjects performed 2 sets of 50 passive arm curls with the dominant arm on an isokinetic dynamometer with a maximal eccentric muscle action superimposed every fourth passive repetition. One repetition maximum elbow flexion, upper arm circumference, relaxed elbow angle, blood serum cortisol, creatine kinase, lactate dehydrogenase, and perception of soreness questionnaires were collected prior to the exercise bout and daily thereafter for 5 days. RESULTS: Creatine kinase was significantly elevated from the baseline value in both groups, although the experimental compression test group showed decreased magnitude of creatine kinase elevation following the eccentric exercise. Compression sleeve use prevented loss of elbow motion, decreased perceived soreness, reduced swelling, and promoted recovery of force production. CONCLUSIONS: Results from this study underline the importance of compression in soft tissue injury management.

Adolescent↗

PubMed1985

Incompatibility of endurance- and strength-training modes of exercise.

Twenty-two male and female subjects trained for 7 wk for endurance (group E), for strength (group IS), or for both strength and endurance (group C) to evaluate the effect of concurrent performance of both modes of training on the in vivo force-velocity relationship of human muscle and on aerobic power. Endurance training consisted of five 5-min sessions three times a week on cycle ergometer with a work load that approached the subject's peak cycle-ergometer O2 uptake (peak CE VO2). Strength training consisted of two 30-s sets of maximal knee extensions per day performed on an isokinetic dynamometer three times a week at a velocity of 4.19 rad X s-1. Group C performed the same training as groups IS and E, alternating days of strength and endurance training. Subjects (groups C and IS) were tested pre- and posttraining for maximal knee-extension torque at a specific joint angle (0.52 rad below horizontal) for seven specific angular velocities (0, 0.84, 1.68, 2.81, 3.35, 4.19, and 5.03 rad X s-1). Groups C and E were tested for peak CE VO2 pretraining, at 14-day intervals, and posttraining. Group IS showed significant increases in angle-specific maximal torque at velocities up to and including the training speed (4.19 rad X s-1). Group C showed increases (P less than 0.05) at velocities of 0, 0.84, and 1.68 rad X s-1 only. Peak CE VO2, when expressed in relative or absolute terms, increased (P less than 0.05) approximately 18% for both groups E and C.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1996

A comparison of isokinetics and muscle strength ratios following intra-articular and extra-articular reconstructions of the anterior cruciate ligament.

A prospective, randomized clinical trial was conducted to compare an intra-articular with an extra-articular reconstruction of the anterior cruciate ligament. Isokinetic muscle testing was carried out 6 months to 2 years following operation using the Biodex isokinetic dynamometer. The extra-articular procedure resulted in a lower deficit for the peak quadriceps and hamstring torques and the range of motion.

Adult↗