The importance of medicinal herbs and plants for sports: an organic way to enhance athletic performance

Data about effects of exercise training in adolescents with intellectual disability (ID) are very limited. This study investigated the effect of 2 different frequencies of the same intensity and total training volume of combined exercise training on indices of body composition, physical fitness, and lipid profile in overweight and obese adolescents with ID. A total of 45 overweight and obese adolescents with ID aged 14-22 years with a total IQ 45-70 received combined exercise training 3 times a week (CET3) for 30 sessions (10 weeks; n = 15), twice a week (CET2) for 30 sessions (15 weeks; n = 15), or no training (10 weeks; n = 15). Groups were matched for age, sex, and education form. Before and after the intervention period, indices of body composition, physical fitness and lipid profile have been evaluated. Compared to the control group, CET3 resulted in a significant improvement of physical fitness, obesity indices, and lipid profile of the participants. Comparing CET2 with CET3, no significantly different evolutions were noticed, except for lower limb strength in favor of exercising 3 times a week. In conclusion, exercising 2 times a week, which is more feasible and practical for participants and guidance, has the same health beneficial effects as 3 times per week in overweight and obese adolescents with ID in short-term training.

BackgroundSkeletal muscle is negatively impacted by conditions such as spaceflight or prolonged bed rest, resulting in a dramatic decline in muscle mass, maximum contractile force, and muscular endurance. Electrical stimulation (ES) is an essential tool in neurophysiotherapy and an effective means of preventing skeletal muscle atrophy and dysfunction. Historically, ES treatment protocols have used either low or high frequency electrical stimulation (LFES/HFES). However, our study tests the use of a combination of different frequencies in a single electrical stimulation intervention in order to determine a more effective protocol for improving both skeletal muscle strength and endurance.MethodsAn adult male SD rat model of muscle atrophy was established through 4 weeks of tail suspension (TS). To investigate the effects of different frequency combinations, the experimental animals were treated with low (20 Hz) or high (100 Hz) frequency before TS for 6 weeks, and during TS for 4weeks. The maximum contraction force and fatigue resistance of skeletal muscle were then assessed before the animals were sacrificed. The muscle mass, fiber cross-sectional area (CSA), fiber type and related protein expression were examined and analyzed to gain insights into the mechanisms by which the ES intervention protocol used in this study regulates muscle strength and endurance.ResultsAfter 4 weeks of unloading, the soleus muscle mass and fiber CSA decreased by 39% and 58% respectively, while the number of glycolytic muscle fibers increased by 21%. The gastrocnemius muscle fibers showed a 51% decrease in CSA, with a 44% decrease in single contractility and a 39% decrease in fatigue resistance. The number of glycolytic muscle fibers in the gastrocnemius also increased by 29%. However, the application of HFES either prior to or during unloading showed an improvement in muscle mass, fiber CSA, and oxidative muscle fibers. In the pre-unloading group, the soleus muscle mass increased by 62%, while the number of oxidative muscle fibers increased by 18%. In the during unloading group, the soleus muscle mass increased by 29% and the number of oxidative muscle fibers increased by 15%. In the gastrocnemius, the pre-unloading group showed a 38% increase in single contractile force and a 19% increase in fatigue resistance, while in the during unloading group, a 21% increase in single contractile force and a 29% increase in fatigue resistance was observed, along with a 37% and 26% increase in the number of oxidative muscle fibers, respectively. The combination of HFES before unloading and LFES during unloading resulted in a significant elevation of the soleus mass by 49% and CSA by 90%, with a 40% increase in the number of oxidative muscle fibers in the gastrocnemius. This combination also resulted in a 66% increase in single contractility and a 38% increase in fatigue resistance.ConclusionOur results indicated that using HFES before unloading can reduce the harmful effects of muscle unloading on the soleus and gastrocnemius muscles. Furthermore, we found that combining HFES before unloading with LFES during unloading was more effective in preventing muscle atrophy in the soleus and preserving the contractile function of the gastrocnemius muscle.

Objective: To determine the correlations between muscle mass, muscle strength, physical performance, and muscle fatigue resistance in community-dwelling elderly people in order to elucidate factors which contribute to elderly’s performance of daily activities. Methods: A cross-sectional study was conducted on community-dwelling elderly in Bandung from September to December 2014. One hundred and thirty elderly, 60 years old or above, were evaluated using bioelectrical impedance analysis to measure muscle mass; grip strength to measure muscle strength and muscle fatigue resistance; habitual gait speed to measure physical performance; and Global Physical Activity Questionnaire (GPAQ) to assess physical activity. Results: There were significant positive correlations between muscle mass (r=0,27, p=0,0019), muscle strength (r=0,26, p=0,0024), and physical performance (r=0,32, p=0,0002) with muscle fatigue resistance. Physical performance has the highest correlation based on multiple regression test (p=0,0025). In association with muscle mass, the physical activity showed a significant positive correlation (r=0,42, p=0,0000). Sarcopenia was identified in 19 (14.61%) of 130 subjects. Conclusions: It is suggested that muscle mass, muscle strength, and physical performance influence muscle fatigue resistance. Keywords: Community-dwelling, elderly, muscle fatigue resistance, muscle mass, sarcopenia DOI: 10.15850/ijihs.v4n1.684

A Comparison of Aerobic Exercise and Resistance Training in Patients With and Without Chronic Kidney Disease

Background Strength training or aerobic exercise programmes might optimise muscle and cardiorespiratory function and prevent additional disuse atrophy and deconditioning in people with a muscle disease. This is an update of a review first published in 2004. Objectives To examine the safety and efficacy of strength training and aerobic exercise training in people with a muscle disease. Search methods We searched the Cochrane Neuromuscular Disease Group Specialized Register (July 2012), CENTRAL (2012 Issue 3 of 4), MEDLINE (January 1946 to July 2012), EMBASE (January 1974 to July 2012), EMBASE Classic (1947 to 1973) and CINAHL (January 1982 to July 2012). Selection criteria Randomised or quasi-randomised controlled trials comparing strength training or aerobic exercise programmes, or both, to no training, and lasting at least six weeks, in people with a well-described diagnosis of a muscle disease. We did not use the reporting of specific outcomes as a study selection criterion. Data collection and analysis Two authors independently assessed trial quality and extracted the data obtained from the full text-articles and from the original investigators. We collected adverse event data from included studies. Main results We included five trials (170 participants). The first trial compared the effect of strength training versus no training in 36 people with myotonic dystrophy. The second trial compared aerobic exercise training versus no training in 14 people with polymyositis and dermatomyositis. The third trial compared strength training versus no training in a factorial trial that also compared albuterol with placebo, in 65 people with facioscapulohumeral muscular dystrophy (FSHD). The fourth trial compared combined strength training and aerobic exercise versus no training in 18 people with mitochondrial myopathy. The fifth trial compared combined strength training and aerobic exercise versus no training in 35 people with myotonic dystrophy type 1. In both myotonic dystrophy trials and the dermatomyositis and polymyositis trial there were no significant differences between training and non-training groups for primary and secondary outcome measures. The risk of bias of the strength training trial in myotonic dystrophy and the aerobic exercise trial in polymyositis and dermatomyositis was judged as uncertain, and for the combined strength training and aerobic exercise trial, the risk of bias was judged as adequate. In the FSHD trial, for which the risk of bias was judged as adequate, a +1.17 kg difference (95% confidence interval (CI) 0.18 to 2.16) in dynamic strength of elbow flexors in favour of the training group reached statistical significance. In the mitochondrial myopathy trial, there were no significant differences in dynamic strength measures between training and non-training groups. Exercise duration and distance cycled in a submaximal endurance test increased significantly in the training group compared to the control group. The differences in mean time and mean distance cycled till exhaustion between groups were 23.70 min (95% CI 2.63 to 44.77) and 9.70 km (95% CI 1.51 to 17.89), respectively. The risk of bias was judged as uncertain. In all trials, no adverse events were reported. Authors' conclusions Moderate-intensity strength training in myotonic dystrophy and FSHD and aerobic exercise training in dermatomyositis and polymyositis and myotonic dystrophy type I appear to do no harm, but there is insufficient evidence to conclude that they offer benefit. In mitochondrial myopathy, aerobic exercise combined with strength training appears to be safe and may be effective in increasing submaximal endurance capacity. Limitations in the design of studies in other muscle diseases prevent more general conclusions in these disorders.

BackgroundLoss of muscle strength and endurance with aging or in various conditions negatively affects quality of life. Resistance exercise training (RET) is the most powerful means to improve muscle mass and strength, but it does not generally lead to improvements in endurance capacity. Free essential amino acids (EAAs) act as precursors and stimuli for synthesis of both mitochondrial and myofibrillar proteins that could potentially confer endurance and strength gains. Thus, we hypothesized that daily consumption of a dietary supplement of nine free EAAs with RET improves endurance in addition to the strength gains by RET.MethodsMale C57BL6J mice (9 weeks old) were assigned to control (CON), EAA, RET (ladder climbing, 3 times a week), or combined treatment of EAA and RET (EAA + RET) groups. Physical functions focusing on strength or endurance were assessed before and after the interventions. Several analyses were performed to gain better insight into the mechanisms by which muscle function was improved. We determined cumulative rates of myofibrillar and mitochondrial protein synthesis using 2H2O labelling and mass spectrometry; assessed ex vivo contractile properties and in vitro mitochondrial function, evaluated neuromuscular junction (NMJ) stability, and assessed implicated molecular singling pathways. Furthermore, whole‐body and muscle insulin sensitivity along with glucose metabolism, were evaluated using a hyperinsulinaemic–euglycaemic clamp.ResultsEAA + RET increased muscle mass (10%, P < 0.05) and strength (6%, P < 0.05) more than RET alone, due to an enhanced rate of integrated muscle protein synthesis (19%, P < 0.05) with concomitant activation of Akt1/mTORC1 signalling. Muscle quality (muscle strength normalized to mass) was improved by RET (i.e., RET and EAA + RET) compared with sedentary groups (10%, P < 0.05), which was associated with increased AchR cluster size and MuSK activation (P < 0.05). EAA + RET also increased endurance capacity more than RET alone (26%, P < 0.05) by increasing both mitochondrial protein synthesis (53%, P < 0.05) and DRP1 activation (P < 0.05). Maximal respiratory capacity increased (P < 0.05) through activation of the mTORC1‐DRP1 signalling axis. These favourable effects were accompanied by an improvement in basal glucose metabolism (i.e., blood glucose concentrations and endogenous glucose production vs. CON, P < 0.05).ConclusionsCombined treatment with balanced free EAAs and RET may effectively promote endurance capacity as well as muscle strength through increased muscle protein synthesis, improved NMJ stability, and enhanced mitochondrial dynamics via mTORC1‐DRP1 axis activation, ultimately leading to improved basal glucose metabolism.

Individuals with Down syndrome (DS) have low levels of muscle strength and aerobic capacity. It has been suggested that the low level of muscle strength impacts the low aerobic capacity in persons with DS, but the relationship between muscle strength and aerobic capacity remains unclear. PURPOSE: To investigate the relationship between muscle strength and aerobic capacity in adults with DS. METHODS: Thirty-six adults (age = 27.6 + 8.1 yrs; weight = 76.1 + 15.1 kg) with DS were recruited. None of the subjects were institutionalized and all were free of cardiovascular disease or muscle problems. Subjects completed a treadmill test to exhaustion with oxygen uptake measurements using validated individualized protocols, and several test of leg muscle strength. Maximal leg extension and flexion strength were evaluated with isokinetic tests at 60 degrees/second, and isometric tests at 45, 60 and 75 degrees of extension. The relationship between aerobic capacity and muscle strength was evaluated using Pearson correlations and a stepwise multiple regression. RESULTS: Aerobic capacity was significantly (p< 01) related to isokinetic extension and flexion peak torque (r=.47 and r=.42 respectively), and to isometric peak torque for both extension and flexion at each of the positions evaluated (correlation coefficients between 0.46-0.57). The stepwise multiple regression revealed that only the peak torque during the isometric leg extension at 75 degrees and the peak torque during the isokinetic leg extension were included in the model as significant predictors of aerobic capacity, yielding the following prediction equation explaining 42% of the variance: VO2 (ml/min) = 2.982 (isometric peak torque) + 3.043 (isokinetic peak torque) + 1024 (R=0.645; p< .001). CONCLUSION: Leg muscle strength was significantly related to aerobic capacity in individuals with DS, and the relationship was higher than what has been reported for other non-disabled populations. However, only two leg extension variables were included in the final model, suggesting the leg flexion strength does not influence aerobic capacity in this population. If aerobic capacity and leg strength are causally related in this population, our data suggest that resistance training may improve aerobic capacity in individuals with DS.

Engaging in both resistance and endurance exercise within the same training program, termed 'concurrent exercise training,' is common practice in many athletic disciplines that require a combination of strength and endurance and is recommended by a number of organizations to improve muscular and cardiovascular health and reduce the risk of chronic metabolic disease. Dietary protein ingestion supports skeletal muscle remodeling after exercise by stimulating the synthesis of muscle proteins and can optimize resistance exercise-training mediated increases in skeletal muscle size and strength; however, the effects of protein supplementation on acute and longer-term adaptive responses to concurrent resistance and endurance exercise are unclear. The purpose of this systematic review is to evaluate the effects of dietary protein supplementation on acute changes in muscle protein synthesis and longer-term changes in muscle mass, strength, and aerobic capacity in responses to concurrent resistance and endurance exercise in healthy adults. A systematic search was conducted in five databases: Scopus, Embase, Medline, PubMed, and Web of Science. Acute and longer-term controlled trials involving concurrent exercise and protein supplementation in healthy adults (ages 18-65years) were included in this systematic review. Main outcomes of interest were changes in skeletal muscle protein synthesis rates, muscle mass, muscle strength, and whole-body aerobic capacity (i.e., maximal/peak aerobic capacity [VO2max/peak]). The quality of studies was assessed using the National Institute of Health Quality Assessment for Controlled Intervention Studies. Four acute studies including 84 trained young males and ten longer-term studies including 167 trained and 391 untrained participants fulfilled the eligibility criteria. All included acute studies demonstrated that protein ingestion enhanced myofibrillar protein synthesis rates, but not mitochondrial protein synthesis rates during post-exercise recovery after an acute bout of concurrent exercise. Of the included longer-term training studies, five out of nine reported that protein supplementation enhanced concurrent training-mediated increases in muscle mass, while five out of nine studies reported that protein supplementation enhanced concurrent training-mediated increases in muscle strength and/or power. In terms of aerobic adaptations, all six included studies reported no effect of protein supplementation on concurrent training-mediated increases in VO2max/peak. Protein ingestion after an acute bout of concurrent exercise further increases myofibrillar, but not mitochondrial, protein synthesis rates during post-exercise recovery. There is some evidence that protein supplementation during longer-term training further enhances concurrent training-mediated increases in skeletal muscle mass and strength/power, but not whole-body aerobic capacity (i.e., VO2max/peak).

Low ponderal index is associated with decreased muscle strength and fatigue resistance in college-aged women

Objective: Investigating the effect of combined aerobic and strength training on metabolic and physical fitness in adults with intellectual disabilities compared to endurance training and no training. Design: A controlled trial with patients receiving either combined (COM), endurance (END) or no training (C). Setting: Two centres for intellectual disabilities (Sterrenhuis, Brasschaat and Emiliani, Lokeren, Belgium). Subjects: Forty-five adults with intellectual disabilities (mean age: 42 (9,2), mean body mass index (BMI): 24 (3,9), mean IQ: 56 (5,6)). Intervention: Combined exercise training (n = 15) and endurance training (n = 15) twice a week for 70 minutes per session for 20 weeks and no training (n = 15). Groups were matched for age, sex and intellectual disability. Main measures: Lipid profile, physical fitness (primary); blood pressure and body composition. Results: Compared to no training, combined exercise training has significant positive effects on total cholesterol levels, aerobic capacity, muscle strength and resting systolic blood pressure, while endurance exercise training has significant effects on aerobic capacity and resting systolic blood pressure. Compared to endurance training, combined exercise training resulted in a significant better evolution of total cholesterol (mean differences: −18 versus −3 mg/dl), 1RM upper (+6 versus +1 kg) and lower limb (+25 versus +8 kg) and abdominal muscles (+15 versus +1 kg), hand grip strength (+9 versus +2 kg), muscle fatigue resistance (+11 versus +5 sec), sit-to-stand (+5 versus +2/30 sec) and systolic blood pressure (−15 versus −10 mmHg). Conclusion: This study revealed a tendency towards more beneficial effects of combined exercise training in adults with intellectual disability.

ABSTRACTPurposeThis study aimed to assess the effects of 20 wk resistance exercise training with or without protein supplementation on body composition, muscle mass, muscle strength, physical performance, and aerobic capacity in prostate cancer patients receiving androgen deprivation therapy (ADT).MethodsSixty prostate cancer patients receiving ADT were randomly assigned to perform 20 wk of resistance exercise training with supplementation of 31 g whey protein (EX + PRO, n = 30) or placebo (EX + PLA, n = 30), consumed immediately after exercise and every night before sleep. A separate control group (CON, n = 36) only received usual care. At baseline and after 20 wk, body composition (dual-energy x-ray absorptiometry), muscle mass (computed tomography scan), muscle strength (1-repetition maximum strength tests), physical performance (Timed Up and Go Test, 30-Second Chair Stand Test, and Stair Climb Test), aerobic capacity (cardiopulmonary exercise test), and habitual dietary intake (food diary) were assessed. Data were analyzed using a two-factor repeated-measures ANOVA.ResultsOver time, muscle mass and strength increased in EX + PRO and EX + PLA and decreased in CON. Total fat mass and fat percentage increased in EX + PRO and CON, but not in EX + PLA. Physical performance did not significantly change over time in either group. Aerobic capacity was maintained in EX + PLA, but it decreased in EX + PRO and CON. Habitual protein intake (without supplements) averaged >1.0 g·kg body weight−1·d−1, with no differences over time or between groups.ConclusionsIn prostate cancer patients, resistance exercise training counteracts the adverse effects of ADT on body composition, muscle mass, muscle strength, and aerobic capacity, with no additional benefits of protein supplementation.

Endurance capacity is essential for endurance athletes' achievement and individuals' health. Nutritional supplements are a proven way to enhance endurance capacity. Previous studies have shown that ferulic acid (FA) enhances endurance capacity, but the underlying mechanism is unclear. The study is aimed to investigate the mechanism by which FA increases endurance capacity. Forty mice are divided into control and 0.5% FA-supplemented groups, and an exhaustive swimming test demonstrates increased endurance capacity with FA supplementation. This study investigates the underlying mechanism for this effect of FA. Firstly, RT-PCR and western blot analysis find that FA increases the transformation from fast to slow muscle fiber. Additionally, adenosine triphosphate concentration, metabolic enzyme activity, and mitochondrial DNA analysis find that FA increases mitochondrial biogenesis and activates nuclear factor erythroid 2-related factor (NRF)1 signaling pathway in muscle. Besides, through antioxidant capacity analysis, this study finds that FA activates NRF2 signaling pathway and improves the antioxidant capacity in muscle. Moreover, inhibiting NRF2 eliminates FA's effect on muscle fiber transformation in C2C12 cells. Our results suggest that FA increases endurance capacity by promoting skeletal muscle oxidative phenotype, mitochondrial function, and antioxidant capacity, which may be related to the NRF1 and NRF2 signaling pathways.

Androgen deprivation therapy (ADT) is effective for slowing tumor growth in prostate cancer (PCa) patients, but results in fatigue and a reduction in muscle power, strength, and functional abilities. Black men have the highest incidence and mortality rates of PCa compared to any other racial or ethnic group, yet they are under represented in previous PCa and exercise studies. Strength training (ST) has been used previously in PCa patients to attenuate some of the side effects of ADT, however, it is unclear whether ADT prevents ST-induced gains in muscle power, a strong predictor of physical function. PURPOSE: To determine the effects of ST on muscle power, strength, fatigue resistance and physical function in black men on ADT for PCa. METHODS: 16 black men (age 58-80) with PCa on ADT were assessed at baseline for upper and lower body strength (1RM). Fatigue resistance was determined by the number of repetitions performed during the chest and leg press at 70% of 1RM before fatigue ensued. Knee extensor peak power was measured as the highest power reached at 50, 60, and 70% of 1 RM. Physical function was estimated using 3 separate walking tests, a stair climb test, and the number of chair stands completed in 30 sec. All assessments were repeated after a 12 wk full-body ST program. Changes with ST were determined using paired T-tests. Associations between improvements in muscle function (strength, power, and fatigue resistance) and physical function were analyzed via a correlation matrix. RESULTS: Knee extensor, chest, and leg press 1RM increased significantly (range 14.5 - 23.8%; all P < 0.01), as did chest and leg press endurance (65% and 149% respectively; all P < 0.001) with ST. All indices of physical function also improved significantly with ST (range 6.5 - 17.4%; all P < 0.05). Peak power significantly increased at all intensities for the right leg and at 50 and 60% for the left leg (range 8.4 - 16.5%, P < 0.05). The strongest correlations were between the changes in power and those in the 6m rapid walk (r = 0.55 - 0.70; P < 0.05). CONCLUSIONS: Despite ablation of testosterone from ADT, ST increases muscle power, strength, fatigue resistance, and physical function in black men on ADT. ST-induced improvements in muscle function are associated with faster walking times in these patients. Supported by NIH grants R21CA127784 and AG000268.

An up-to-date overview of the effectiveness and safety of dynamic exercise therapy (exercise therapy with a sufficient intensity, duration, and frequency to establish improvement in aerobic capacity and/or muscle strength) is lacking. To assess the effectiveness and safety of short-term (< three months) and long-term (> three months) dynamic exercise therapy programs (aerobic capacity and/or muscle strength training), either land or water-based, for people with RA. To do this we updated a previous Cochrane review (van den Ende 1998) and made categories for the different forms of dynamic exercise programs. A literature search (to December 2008) within various databases was performed in order to identify randomised controlled trials (RCTs). RCTs that included an exercise program fulfilling the following criteria were selected: a) frequency at least twice weekly for > 20 minutes; b) duration > 6 weeks; c) aerobic exercise intensity > 55% of the maximum heart rate and/or muscle strengthening exercises starting at 30% to 50% of one repetition maximum; and d) performed under supervision. Moreover, the RCT included one or more of the following outcome measures: functional ability, aerobic capacity, muscle strength, pain, disease activity or radiological damage. Two review authors independently selected eligible studies, rated the methodological quality, and extracted data. A qualitative analysis (best-evidence synthesis) was performed and, where appropriate, a quantitative data analysis (pooled effect sizes). In total, eight studies were included in this updated review (two additional studies). Four of the eight studies fulfilled at least 8/10 methodological criteria. In this updated review four different dynamic exercise programs were found: (1) short-term, land-based aerobic capacity training, which results show moderate evidence for a positive effect on aerobic capacity (pooled effect size 0.99 (95% CI 0.29 to 1.68). (2) short-term, land-based aerobic capacity and muscle strength training, which results show moderate evidence for a positive effect on aerobic capacity and muscle strength (pooled effect size 0.47 (95% CI 0.01 to 0.93). (3) short-term, water-based aerobic capacity training, which results show limited evidence for a positive effect on functional ability and aerobic capacity. (4) long-term, land-based aerobic capacity and muscle strength training, which results show moderate evidence for a positive effect on aerobic capacity and muscle strength. With respect to safety, no deleterious effects were found in any of the included studies. Based on the evidence, aerobic capacity training combined with muscle strength training is recommended as routine practice in patients with RA.

When I was asked to write an editorial to comment on the article by Simon et al (1) in this issue of the Journal, I felt it would be a real challenge. The use of GH therapy in children has provoked more discussion in the last few years from a legal, journalistic, economical, and even political point of view than from medical and scientific perspectives. I decided to take the challenge and to comment on the facts as I perceive them. An impact of recombinant human GH (rhGH) on muscle strength is controversial. As physicians, we are essentially warned about rhGH doping in professional and Olympic athletics, with the presumption that it has a beneficial effect on muscle strength. This is despite the fact that there appears to be no evidence that rhGH enhances muscle strength, power, or aerobic capacity in trained adult athletes. However, rhGH does increase modestly anaerobic exercise capacity when administered alone and to a greater extent when combined with testosterone (2). Thus, despite the abuse of rhGH by athletes, there is little support of performance benefit except for an effect on anaerobic exercise capacity (2). In GH-deficient patients, replacement of rhGH improves aerobic exercise capacity, although it remains to be elucidated whether this is due to the direct effect on muscle function or on other factors influencing cardiovascular function, well-being, and motivation. Long-term rhGH replacement in excess of 12 months seems to be required for improved muscle strength to take place in GH-deficient adult subjects (2). It has been reported that 10 years of rhGH replacement therapy in GH-deficient adults increased muscle strength during the first half of the study and then protected partly against the normal decline withage inmusclestrength,resulting inapproximatelynormalized muscle strength after 10 years (3). Even fewerdataareavailable inchildren,with theexception of data gathered from children affected with Prader-Willi syndrome(PWS),araregenetic formofobesitywithhypothalamic involvement that leads to GH deficiency. One group assessed the impact of rhGH therapy begun early in life on the natural history of PWS and compared height, body composition, and strength in similar-age children with PWS naive to rhGH with those treated with hGH for 6 years (4). Motor strength testing included broad jump, agility run, sit-ups, and upper arm strength assessments. The evaluator of motor strength testing was blinded to the treatment status of each child. PWS children treated with rhGH demonstrated greater motor strength (increased standing broad jump 22.9 2.1 vs 14.6 1.9 inches (P .001) and sit-ups 12.4 0.9 vs 7.1 0.7 repetitions in 30 seconds; P .001). Clear trends were seen in the 2 other areas of the testing, including improved agility run and weight-lift repetitions, although these did not reach statistical significance. Thus, thisnonrandomizedstudysuggestedabeneficialeffecton muscle strength in children affected by PWS. However, these few reports on young active adults, on GH-deficient adults, and on children affected by PWS may not be relevant to the chronically ill and less active children included in the study of Simon et al (1). In this study, the authors evaluated the effects of rhGH on muscle strength in children receiving long-term glucocorticoid therapy. Expected effects of growth hormone on height and body composition were assessed and confirmed, but those will not be commented upon here. This was a pilot study, randomized and controlled, with a delayed-start of rhGH for 12 months. rhGH was started after randomization (month 0) or 6 months later (month 6). A total of 30 children with various diagnoses, on glucocorticoid therapy for a chronic disease, startedat least1year earlierwithheight1SDorat2SDscore (SDS) below and bone age 15 years in boys and 13 years in girls. rhGH was administered at a dose of 0.065 mg/kg/d for 6monthsandtheninthedosagemaintainingserumIGF-1levels