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PubMed1998

Modelling the relationship between isokinetic muscle strength and sprint running performance.

Muscle strength is thought to be a major factor in athletic success. However, the relationship between muscle strength and sprint performance has received little attention. The aim of this study was to examine the relationship in elite performers of isokinetic muscle strength across three lower limb joints and sprinting performance, including the use of theoretical models. Eight rugby players, eight track sprinters and eight competitive sportsmen, all elite national or regional competitors, performed sprints over 15 m and 35 m with times recorded over 0-15 m and 30-35 m. Isokinetic torque was measured at the knee, hip and ankle joints at low (1.05 rad s(-1)), intermediate (2.09 or 2.62 rad s(-1)) and high (3.14 or 4.19 rad s(-1)) speeds during concentric and eccentric muscle actions. Using linear regression and expressing sprint performance as time, the strongest relationship, for the joint actions and speeds tested, was between concentric knee extension at 4.19 rad s(-1) and sprint performance (0-15 m times: r=-0.518, P< 0.01; 30-35 m times: r=-0.688, P< 0.01). These relationships were improved for 0-15 m, but not for 30-35 m, by expressing torque relative to body mass (0-15 m times: r=-0.581; 30-35 m times: r=-0.659). When 0-15 m performance was expressed as acceleration rather than time, the correlation was improved slightly (r=0.590). However, when the data (0-15 m times) were fitted to the allometric force model proposed by Gunther, 77% of the variance in concentric knee extension torque at 4.19 rad s(-1) could be explained by 0-15 m times, limb length (knee to buttocks) and body mass. The fitted parameters were similar to those from the theoretical model. These findings suggest that the relationship between isokinetic muscle strength and sprint performance over 0-15 m (during the acceleration phase) is improved by taking limb length and body mass into account.

Analysis of Variance↗

PubMed1994

[Changes in abdominal muscle strength with respect to aging].

It has been generally agreed that muscle strength decreases with advance of age in adulthood. In order to study the effect of aging in abdominal muscle strength, abdominal muscle strength, height, body weight and grip strength were measured in 144 healthy subjects aged from 20 to 88 years old. The abdominal muscle strength was measured using a grip dynamometer. Curve between aging and strength revealed that the abdominal muscle strength gradually decreased with aging during many decades, but rapidly decreased in the fifth decade and over in males and seventh decade and over in females. Among these data, significant correlations were observed between abdominal muscle strength and age (only in males; r = -0.64), abdominal muscle strength and grip strength (in males; r = 0.75, in females; r = 0.47), age and grip strength (in males; -0.72, in females; r = -0.60), and, age and height (in males; r = -0.55, in females; r = -0.46). The results suggest that decrease of abdominal muscle strength is due to aging, although the degree of the decrease is affected by the generation studied. The method to measure abdominal muscle strength originally developed by us is easy and useful to understand changes of age-related muscular strength.

Abdominal Muscles↗

PubMedDate not supplied

Manual muscle strength testing: intraobserver and interobserver reliabilities for the intrinsic muscles of the hand.

The reliability of manual muscle strength testing of the intrinsic muscles of the hand is reported. The muscle strengths of 28 patients who had neuropathies of the ulnar nerve or the ulnar and median nerves were graded by two physiotherapists to determine intraobserver and interobserver reliabilities. Muscle strength was graded using the numeric scale developed by the Medical Research Council (grades 0 to 5). Reliabilities were established for nine muscles or muscle groups. Intraobserver reliabilities ranged from 0.71 to 0.96 and interobserver reliabilities from 0.72 to 0.93. It is difficult to isolate, and hence grade, most of the intrinsic muscles of the hand. Therefore, it is suggested that specific movements be tested and graded when assessing and evaluating muscle or nerve function.

Adult↗

PubMed2003

Muscle strength and endurance do not significantly vary across 3 phases of the menstrual cycle in moderately active premenopausal women.

OBJECTIVE: To investigate muscle strength and muscle endurance in women during 3 well-determined phases of the menstrual cycle: early follicular phase, ovulation phase, and midluteal phase. DESIGN: Prospective, within-woman analysis was performed of muscle strength and muscle endurance by repeated measures analysis of variance in 3 hormonally verified phases of 2 consecutive menstrual cycles. PARTICIPANTS: Fifteen female subjects with moderate physical activity level and regular menstrual cycles volunteered to participate in the study. Analyses are based on 10 subjects who completed 2 consecutive menstrual cycles with hormonally verified phases. MAIN OUTCOME MEASUREMENTS: Handgrip strength, 1-leg hop test, isokinetic muscle strength, and muscle endurance were measured in 2 consecutive menstrual cycles in the early follicular phase, in the ovulation phase, and in the midluteal phase. Isokinetic muscle strength and endurance were tested with knee extension exercise on a standard instrument. Menstrual cycle phases were determined by analysis of sex hormone levels in serum, and ovulation was detected by luteinizing hormone surge in urine. RESULTS: No significant variation in muscle strength or muscle endurance could be detected during different well-determined phases of the menstrual cycle. CONCLUSIONS: This study detected no significant variation in muscle strength and muscle endurance during the menstrual cycle. In contrast to other studies showing variations in strength and endurance during the menstrual cycle, the present study was hormonally validated and was repeated in 2 consecutive menstrual cycles. However, it is unknown whether these data in moderately active university students would be relevant to the highly trained woman athlete.

Adult↗

PubMed2001

Muscle strength, pain and disability in patients with osteoarthritis.

OBJECTIVE: Reduced muscle strength is regarded as a risk factor for pain and disability in osteoarthritis (OA). Currently, various indices for muscle strength are used when assessing determinants of pain and disability. The goal of the present study was to evaluate these indices of muscle strength. DESIGN: Isometric muscle strength was measured for 16 muscle actions around the knees and hips in 52 patients with OA of the hip and 70 patients with OA of the knee. Various indices of muscle strength were derived from these measurements, applying five alternative approaches. These approaches ranged from a single overall index to a set of 16 separate indices. The internal consistency of these indices was determined (Cronbach's alpha), and it was determined to what extent they could reveal the association between reduced muscle strength on the one hand and pain and disability on the other hand. RESULTS: Internal consistency was satisfactory for all indices (Cronbach's alpha >0.74). As expected, reduced muscle strength was associated with increased disability, but no clear relationship could be established between muscle weakness and pain. The strength of these associations did not depend on the approach used to derive the indices for muscle strength. CONCLUSIONS: The indices did not show major differences with regard to internal consistency or the extent to which the association with pain and disability could be revealed. For reasons of parsimony, approaches resulting in few indices appear to be most useful. However, muscle strength was found to be significantly reduced around affected joints, compared with muscle strength around unaffected joints. Therefore, the most suitable approach for reducing muscle strength data into indices is one that results in as few indices as possible, but with separate indices for muscle strength around affected and unaffected joints.

Aged↗

PubMed2003

Cervical muscle strength after laminoplasty.

To determine changes in cervical muscle strength after laminoplasty and to evaluate the relation between muscle strength and neck pain, we measured maximum isometric muscle strength using a handheld dynamometer. We also investigated neck pain before surgery and every month after surgery in 21 subjects who had undergone French-door laminoplasty. Muscle strength decreased particularly 1 month after surgery, the extensor muscles being affected more than the flexors. The strength of both muscle groups increased gradually; and at 1 year after surgery they had regained their presurgical status. All of the subjects complained of severe neck pain after 1 month. Their complaints began to decrease a few months after surgery, although they were still present in nine patients at 1 year after surgery. The correlation between muscle strength and neck pain was strongly negative for extension and flexion in men and for extension in women. No correlation was found between flexor muscle strength and neck pain in women. The extension/flexion ratio was significantly high in the neck pain group 1 year after surgery. Our results suggest that symptoms within a few months after surgery are due to surgical trauma to the soft tissues but that chronic neck pain derives from an imbalance of the two muscle strengths.

Aged↗

PubMed2006

Respiratory muscle strength training: functional outcomes versus plasticity.

Respiratory muscle strength training is a paradigm that has been used for numerous years with a variety of populations including but not limited to spinal cord injury, chronic obstructive pulmonary disease, multiple sclerosis, Parkinson's disease, voice disordered, sedentary elderly, and healthy young. The respiratory muscle strength program discussed here is an expiratory muscle strength training and uses a pressure threshold device with a regimented treatment protocol. The primary purpose of the expiratory muscle strength training program is to promote strength in the expiratory muscles. The training protocol occurs five times per day, 5 days a week, and consists of ~15-20 minutes per day of training by the user at home. The device threshold is changed weekly by a clinician to maintain a threshold load of 75% of an individual's maximum expiratory pressure. The threshold setting of the device is always based on the individual's recorded maximum expiratory pressure generated into a digital pressure gauge. Results of 4 weeks of expiratory muscle strength training protocols indicate up to a 50% improvement for healthy subjects, those with multiple sclerosis, and those with spinal cord injury. The potential transfer of expiratory muscle strength to functional outcomes is discussed, as well as how strength-training paradigms may influence cortical plasticity.

Breathing Exercises↗

PubMed2001

Calf muscle strength in humans.

In an effort to measure strength characteristics of the calf muscles, 18 subjects (14 male, 4 female, age =34.3+/-2.4yrs) were tested using a specially designed torque velocity device (TVD). This TVD is a hardware interface with the subject's lower leg which stabilizes the leg for calf muscle strength measurements. Calf muscle strength measurements consisted of 1) isometric force production at ankle angles of 80, 90, and 100 degrees of plantar flexion, 2) peak torque at six isokinetic angular velocities 0.52, 1.05, 2.09, 3.14, 4.19, and 5.24 rad x s(-1), and 3) a fatigue test consisting of 30 maximal contractions at 3.14 rad x s(-1). The greatest force production occurred at 80 degrees of ankle plantar flexion (148.5 +/- 40.2 Nm). Isokinetic force production ranged from 114.1 +/- 24.7 Nm at 0.52 rad x s(-1) to 16.8 +/- 6.5 Nm at 5.24 rad x s(-1). A fatigue test consisting of 30 maximal repetitions at 3.14 rad x s(-1) resulted in a 61 +/- 15% decline in force production. To assess reproducibility and day to day variation, measurements at 1.05 and 2.09 rad x s(-1) were made during five different trials in a single day and one trial per day for three days, respectively. The within subject coefficient of variation was 2.6 to 6.5% for reproducibility and 1.9 to 7.4% for day to day variation. Magnetic resonance imaging (MRI) of the lower limb and muscle biopsy specimens from the gastrocnemius (lateral head) and soleus muscles were obtained to examine the relationship between strength and morphological characteristics of the calf muscles. Cross-sectional area of the primary plantar flexors (gastrocnemius and soleus) was 47.9 +/- 1.3 cm2 while muscle volume was 642 +/- 16 cm3. Muscle fiber composition of the gastrocnemius and soleus averaged 57 +/- 2 and 85 +/- 3% type I fibers, respectively. A poor correlation was found between fiber type and maximal isometric force production (r =0.38; p>0.05). However, calf muscle strength and muscle size was positively correlated (r = 0.76; p < 0.05). These data indicate that using the TVD interface to stabilize the lower leg is a reliable and reproducible procedure for the measurement of calf muscle strength.

Adult↗

PubMedDate not supplied

Sensible manual muscle strength testing to evaluate and monitor strength of the intrinsic muscles of the hand: a commentary.

Hand therapists often assess, evaluate, and monitor the status of, and changes in the strength of, the intrinsic muscles of the hand. Some common indications are peripheral and central neuropathies and nerve lacerations and repairs. The therapist will often use a muscle chart that lists all the muscles innervated by the ulnar and median nerves, and all muscles will be tested. Not all muscles in the hand can be sufficiently isolated to grade their strength, nor is it always necessary to test all muscles innervated by a particular nerve to evaluate the presence or extent of motor function impairment or monitor changes. This paper discusses the tests by which changes in strength of the ulnar and median innervated intrinsic muscles can be assessed and the reasons that certain muscles cannot or need not be tested. Information about the reliability of muscle testing is also given.

Exercise Test↗

PubMed2003

Decreased muscle strength and contents of Mg and Na,K-pumps in chronic alcoholics occur independently of liver cirrhosis.

OBJECTIVES: To evaluate the influence of established liver cirrhosis on muscle strength and muscle contents of magnesium (Mg), potassium (K) and sodium, potassium pumps (Na,K-pumps) in chronic alcoholic patients. DESIGN: An open cross-sectional study. SETTING AND SUBJECTS: Forty consecutive chronic alcoholics (18 with cirrhosis and 22 without cirrhosis) admitted to the Department of Hepatology, Aarhus University Hospital, Denmark, or to a collaborating alcoholism treatment centre, and 36 healthy control subjects. MAIN OUTCOME MEASURES: Evaluation of participant's subjective physical ability and measurement of maximum isokinetic muscle strength and muscle mass, as well as measurements of Mg, K and Na,K-pumps in skeletal muscle. RESULTS: Maximum isokinetic muscle strength and muscle mass were equally reduced in patients with and without cirrhosis (P < 0.01 all). In keeping with this, both groups of patients felt equally physically restricted. Muscle Mg was reduced to the same extent in the two groups of patients (by 12 and 9%, P < 0.001, both), whereas the muscle K content was only significantly lower in the cirrhotic patients (10%, P < 0.001). The muscle content of Na,K-pumps was reduced by 14%, (P < 0.01) in the cirrhotic patients and by 8% (P < 0.05) in the noncirrhotic patients. CONCLUSION: Our alcoholic patients complained of physical disability, had reduced skeletal muscle mass, isokinetic muscle strength, content of muscle Mg and content of Na,K-pumps. There was no difference between patients with and without cirrhosis. It appears that it is the heavy alcohol intake, and not the cirrhosis per se, that is responsible for the observed defects.

Adult↗

PubMed1998

Racial differences in muscle strength in disabled older women.

This study examines racial differences in muscle strength, and associations of muscle strength to level of physical activity and severity of disability, among a community sample of 254 black and 665 white, moderately to severely disabled women aged 65 and older. Potential confounders that were adjusted for in the models included age, body weight and height, joint pain, number of chronic conditions, and socioeconomic status. Hand grip, hip flexion, and knee extension forces were measured using portable hand-held dynamometers in the participants' homes. Hand grip strength was measured as the maximal isometric force. Hip flexion and knee extension forces were measured as the greatest force the tester had to apply to break the isometric contraction. A declining strength gradient was observed with increasing severity of disability and for decreasing level of physical activity in both races. At equal levels of disability or physical activity, blacks had better hand grip and hip flexion strength, but knee extension strength did not differ by race. The greater hand grip and hip flexion strength found in black women may be related to their greater muscle mass and known racial differences in body dimensions. No consistent racial differences were observed in the relationship between physical activity and muscle strength, or muscle strength and disability, suggesting that the role of muscle strength in the disablement process does not differ between races. Physical activity and exercise programs may be feasible ways to prevent worsening of disability in blacks and whites.

Aged↗

PubMed2002

Muscle strength testing: use of normalisation for body size.

Assessment of muscle strength tests has been a popular form of testing muscle function in sports and exercises, as well as in other movement-related sciences for several decades. Although the relationship between muscle strength and body size has attracted considerable attention from researchers, this relationship has been often either neglected or incorrectly taken into account when presenting the results from muscle strength tests. Two specific problems have been identified. First, most of the studies have presented strength data either non-normalised for body size, or normalised using inappropriate methods, or even several different normalisations have been applied on the same sets of data. Second, the role of body size in various movement performances has been neglected when functional movement performance was assessed by muscle strength. As a consequence, muscle function, athletic profiles, or functional movement performance assessed by tested muscle strength have been often confounded by the effect of body size. Differences in the normalisation methods applied also do not allow for comparison of the data obtained in different studies. Using the following allometric formula for obtaining index of muscle strength, S, independent of body size (assessed by body mass, m) should be recommended in routine strength testing procedures: The allometric parameter should be either b = 0.67 for muscle force (recorded by a dynamometer), or b = 1 for muscle torque (recorded by an isokinetic apparatus). We also recommend using body-size-independent indices of both muscle strength and movement performance when assessing functional performance from recorded muscle strength or vice versa.

Adolescent↗

PubMed2003

Muscle strength in patients with chronic pain.

OBJECTIVE: To analyse the influence of chronic pain on muscle strength. DESIGN: Muscle strength of patients with unilateral nonspecific chronic pain, in an upper or lower limb, were measured according to a standardized protocol using a hand-held dynamometer. Before and after muscle strength measurement, a visual analogue scale for pain intensity was assessed. RESULTS: Forty patients were measured and the muscle strength of the painful side was 20-30% less than that of the nonpainful side. Strength reduction was seen in the whole limb. A significant correlation between pain intensity and reduced muscle strength in the painful limb existed for hip flexion, knee flexion, knee extension and three-point grip. CONCLUSIONS: A strength reduction of 20-30% in a painful limb seems to be 'normal' in chronic pain patients.

Adult↗

PubMed1991

The relationship between muscle mass and muscle strength in the elderly.

To determine the extent that muscle mass is predictive of muscle strength in the elderly, anthropomorphic estimates of muscle area and impedance measurements of muscle mass and peak isometric muscle strength were obtained in a relatively healthy older population over 65 years of age (mean age = 71.7; n = 218). Midarm muscle area correlated strongly with upper arm strength (r = 0.68, P less than 0.0001) while midthigh muscle area had a much lower correlation with thigh muscle strength (r = 0.29, P less than 0.0001). These muscle area calculations also include bone area. Lean body mass calculated by bioelectric impedance correlated highly with cumulative muscle strength measured by summing all muscle groups (r = 0.79, P less than 0.0001). To determine whether aging alters muscle strength per unit of muscle mass, additional middle-aged subjects were included, and three groups, middle-aged (55-64) (n = 78), young-old (65-74) (n = 161), and old-old (75+) (n = 57), were compared. A significant age-related trend of decreasing muscle strength per unit of lean body mass was noted. It is concluded that although muscle mass correlates with muscle strength in a healthy older population, use of simple age-independent clinical measurements of body mass should not be used to predict muscle strength.

Aged↗

PubMed1996

Normal insulin release during sustained hyperglycaemia in hypokalaemic periodic paralysis: role of the potassium channel opener pinacidil in impaired muscle strength.

1. Hypokalaemic periodic paralysis is characterized by attacks of muscle weakness. Glucose, insulin and an abnormal regulation of ATP-sensitive potassium channels may be involved in these attacks. We studied the effect of hyperglycaemia and of the potassium channel opener pinacidil on insulin release and muscle strength in patients with hypokalaemic periodic paralysis. 2. Insulin release was assessed on two occasions in four patients with hypokalaemic periodic paralysis and in eight matched control subjects, with and without treatment with 25 mg pinacidil orally, during a hyperglycaemic glucose clamp at a blood glucose level of 10 mmol/l, in a placebo-controlled, double-blind study. Muscle strength was measured in the hypokalaemic periodic paralysis patients before and during hyperglycaemia using a handheld dynamometer. 3. During the clamp, the mean glucose concentration (10-180 min) in control subjects was 9.9 +/- 0.07 and 10.0 +/- 0.03 mmol/l with and without pinacidil respectively, and in patients with hypokalaemic periodic paralysis was 10.0 +/- 0.04 and 10.1 +/- 0.06 mmol/l respectively (not significantly different). In both groups, the areas under the insulin curve from 0 to 10 min (first-phase insulin release) and from 30 to 180 min (second phase) were not different on the pinacidil study day compared with on the placebo day. The areas under the insulin curve of the first and second phases also did not differ between control subjects and patients with hypokalaemic periodic paralysis (with or without pinacidil). The M/I ratio, a measure of insulin sensitivity, was not different in the two groups. On the placebo day, baseline muscle strength in patients with hypokalaemic periodic paralysis was 165 +/- 16 N for the hip abductors and 168 +/- 19 N for the knee flexors. During the period of hyperglycaemia on the placebo day, muscle strength did not decrease in either muscle group. On the pinacidil study day, an increase in muscle strength was found only in the two hypokalaemic periodic paralysis patients with the lowest mean muscle strength (< 150 N) on the placebo day. The two hypokalaemic periodic paralysis patients with a mean muscle strength on the placebo day > 150 N showed no increase in muscle strength with pinacidil. 4. Insulin secretion and sensitivity were normal in patients with hypokalaemic periodic paralysis. Hyperglycaemia during hyperglycaemic clamping did not provoke paralytic attacks and did not result in a decrease in muscle strength. The potassium channel opener pinacidil had no effect on insulin secretion in hypokalaemic periodic paralysis patients or in normal subjects. Pinacidil may enhance muscle strength in those hypokalaemic periodic paralysis patients who suffer partial paralytic attacks.

Adult↗

PubMed2002

Avoidance of activity and disability in patients with osteoarthritis of the knee: the mediating role of muscle strength.

OBJECTIVE: Avoidance of activity is hypothesized to lead to muscle weakness and consequently, to physical disability. This study was undertaken to validate the avoidance model by providing evidence for the mediating role of muscle weakness in the relationship between avoidance of activity and physical disability in patients with osteoarthritis (OA) of the knee. METHODS: Data on avoidance of activity, observed physical disability, and muscle strength of the knee in 107 patients with knee OA were analyzed. A series of regression analyses was performed to establish the mediating role of muscle weakness. First, the effect of avoidance of activity on the level of disability was assessed. Next, the relationship between avoidance of activity and muscle strength was established. Finally, the mediating role of muscle strength could be established if the effect of avoidance of activity on disability decreased when muscle strength was taken into account. RESULTS: Initially, avoidance of activity accounted for 21.5% of variance in disability. Avoidance of activity also accounted for 3.9% of variance in muscle strength. After muscle strength was taken into account, the variance in disability accounted for by avoidance of activity was reduced from 21.5% to 15.7%. Thus, the criteria for establishing the mediating role of muscle strength were met. CONCLUSION: The results of this study provide evidence for the mediating role of muscle weakness in the relationship between avoidance of activity and disability in patients with knee OA.

Aged↗

PubMed2005

Serum albumin and muscle strength: a longitudinal study in older men and women.

OBJECTIVES: To examine whether low serum albumin is associated with low muscle strength and future decline in muscle strength in community-dwelling older men and women. DESIGN: Population-based cohort study. SETTING: The Longitudinal Aging Study Amsterdam. PARTICIPANTS: Six hundred seventy-six women and 644 men aged 65 to 88. MEASUREMENTS: Serum albumin was determined at baseline. Muscle strength was assessed using grip strength at baseline, after 3 (n=1,009), and 6 (n=741) years. The outcomes were continuous baseline muscle strength, 3- and 6-year change in muscle strength, and a dichotomous indicator for substantial decline (a decrease if > or =1 standard deviations for women=11 kg, for men=12 kg) in muscle strength. RESULTS: Mean serum albumin concentration+/-standard deviation was 45.0+/-3.3 g/L for women and 45.2+/-3.2 g/L for men. At baseline, adjusting for age, lifestyle factors, and chronic conditions, lower serum albumin was cross-sectionally associated with weaker muscle strength (P<.001) in women and men. After 3 years of follow-up, mean decline in muscle strength was -5.6+/-10.9 kg in women and -9.6+/-11.9 kg in men. After adjustment for potential confounders, lower serum albumin was associated with muscle strength decline over 3 years (P<.01) in women and men (beta=0.57, standard error (SE)=0.18; beta=0.37, SE=0.16, respectively). Lower serum albumin was also associated with substantial decline in muscle strength in women (per unit albumin (g/L) adjusted odds ratio (OR)=1.14, one-sided 95% confidence limit (CL)=1.07) and men (per unit albumin (g/L) adjusted OR=1.14, 95% CL=1.08). Similar but slightly weaker associations were found between serum albumin and 6-year change in muscle strength (P<.05). CONCLUSION: These results suggest that low serum albumin, even within the normal range, is independently associated with weaker muscle strength and future decline in muscle strength in older women and men.

Aged↗

PubMed2005

The effect of resistance training combined with timed ingestion of protein on muscle fiber size and muscle strength.

Acute muscle protein metabolism is modulated not only by resistance exercise but also by amino acids. However, less is known about the long-term hypertrophic effect of protein supplementation in combination with resistance training. The present study was designed to compare the effect of 14 weeks of resistance training combined with timed ingestion of isoenergetic protein vs carbohydrate supplementation on muscle fiber hypertrophy and mechanical muscle performance. Supplementation was administered before and immediately after each training bout and, in addition, in the morning on nontraining days. Muscle biopsy specimens were obtained from the vastus lateralis muscle and analyzed for muscle fiber cross-sectional area. Squat jump and countermovement jump were performed on a force platform to determine vertical jump height. Peak torque during slow (30 degrees s-1) and fast (240 degrees s-1) concentric and eccentric contractions of the knee extensor muscle was measured in an isokinetic dynamometer. After 14 weeks of resistance training, the protein group showed hypertrophy of type I (18% +/- 5%; P < .01) and type II (26% +/- 5%; P < .01) muscle fibers, whereas no change above baseline occurred in the carbohydrate group. Squat jump height increased only in the protein group, whereas countermovement jump height and peak torque during slow isokinetic muscle contraction increased similarly in both groups. In conclusion, a minor advantage of protein supplementation over carbohydrate supplementation during resistance training on mechanical muscle function was found. However, the present results may have relevance for individuals who are particularly interested in gaining muscle size.

Adult↗