We tested the hypothesis that the expansion of satellite cell numbers, 24 h after maximal eccentric knee extensor exercise, is blunted in older men. Muscle biopsies were obtained from the vastus lateralis of 10 young (23-35 years) and 9 older (60-75 years) men. Satellite cells were identified immunohistochemically using an antibody to neural cell adhesion molecule. After 92 maximal eccentric contractions, the mean number of satellite cells per muscle fiber increased to a greater extent among the young men (141%; P < 0.001) than older men (51%; P = 0.002) from preexercise levels. Similar results were obtained when satellite cells were expressed as a proportion of all sublaminar nuclei. We conclude that a single bout of maximal eccentric exercise increases satellite cell numbers in both age groups, with a significantly greater response among the young men. These data suggest that age-related changes in satellite cell recruitment may contribute to muscle regeneration deficits among the elderly.

Context: Impairments in the pituitary-gonadal axis with aging are associated with loss of muscle mass and function and accumulation of upper body fat. Objectives: We tested the hypothesis that physiological supplementation with testosterone and GH together improves body composition and muscle performance in older men. Design, Setting, and Participants: One hundred twenty-two community-dwelling men 70.8 4.2 yr of age with body mass index of 27.4 3.4 kg/m 2 , testosterone of 550 ng/dl or less, and IGF-I in lower adult tertile (167 ng/dl) were randomized to receive transdermal testosterone (5 or 10 g/d) during a Leydig cell clamp plus GH (0, 3, or 5 g/kg d) for 16 wk. Main Outcome Measures: Body composition by dual-energy x-ray absorptiometry, muscle performance , and safety tests were conducted. Results: Total lean body mass increased (1.0 1.7 to 3.0 2.2 kg) as did appendicular lean tissue (0.4 1.4 to 1.5 1.3 kg), whereas total fat mass decreased by 0.4 0.9 to 2.3 1.7 kg as did trunk fat (0.5 0.9 to 1.5 1.0 kg) across the six treatment groups and by dose levels for each parameter (P 0.0004 for linear trend). Composite maximum voluntary strength of upper and lower body muscles increased by 14 34 to 35 31% (P 0.003 in the three highest dose groups) that correlated with changes in appendicular lean mass. Aerobic endurance increased in all six groups (average 96 137sec longer). Systolic and diastolic blood pressure increased similarly in each group with mean increases of 12 14 and 8 8 mm Hg, respectively. Other predictable adverse events were modest and reversible. Conclusions: Supplemental testosterone produced significant gains in total and appendicular lean mass, muscle strength, and aerobic endurance with significant reductions in whole-body and trunk fat. Outcomes appeared to be further enhanced with GH supplementation. (J Clin Endocrinol Metab A lterations in body composition, physical function, and sub-strate metabolism occur with advancing age. Loss of skeletal muscle mass (sarcopenia) (1, 2) contributes to declines in muscle strength and function along with diminished quality of life (3). In the Baltimore Longitudinal Aging Study, quadriceps strength decreased about 30% between 50-70 yr of age (4). In the Copenhagen Heart Study, leg strength in 80-yr-olds was 20-30% lower than in 70-yr-olds (5, 6). Substantial losses in

BackgroundProstate cancer patients on androgen deprivation therapy (ADT) experience adverse effects such as lean mass loss, known as sarcopenia, fat gain, and changes in cardiometabolic factors that increase risk of metabolic syndrome (MetS). Resistance training can increase lean mass, reduce body fat, and improve physical function and quality of life, but no exercise interventions in prostate cancer patients on ADT have concomitantly improved body composition and MetS. This pilot trial investigated 12 weeks of resistance training on body composition and MetS changes in prostate cancer patients on ADT. An exploratory aim examined if a combined approach of training and protein supplementation would elicit greater changes in body composition.MethodsProstate cancer patients on ADT were randomized to resistance training and protein supplementation (TRAINPRO), resistance training (TRAIN), protein supplementation (PRO), or control stretching (STRETCH). Exercise groups (EXE = TRAINPRO, TRAIN) performed supervised exercise 3 days per week for 12 weeks, while non-exercise groups (NoEXE = PRO, STRETCH) performed a home-based stretching program. TRAINPRO and PRO received 50 g⋅day− 1 of whey protein. The primary outcome was change in lean mass assessed through dual energy x-ray absorptiometry. Secondary outcomes examined changes in sarcopenia, assessed through appendicular skeletal mass (ASM) index (kg/m2), body fat %, strength, physical function, quality of life, MetS score and the MetS components of waist circumference, blood pressure, glucose, high-density lipoprotein-cholesterol, and triglyceride levels.ResultsA total of 37 participants were randomized; 32 participated in the intervention (EXE n = 13; NoEXE n = 19). At baseline, 43.8% of participants were sarcopenic and 40.6% met the criteria for MetS. Post-intervention, EXE significantly improved lean mass (d = 0.9), sarcopenia prevalence (d = 0.8), body fat % (d = 1.1), strength (d = 0.8–3.0), and prostate cancer-specific quality of life (d = 0.9) compared to NoEXE (p < 0.05). No significant differences were observed between groups for physical function or MetS-related variables except waist circumference (d = 0.8).ConclusionsA 12-week resistance training intervention effectively improved sarcopenia, body fat %, strength and quality of life in hypogonadal prostate cancer patients, but did not change MetS or physical function. PRO did not offer additional benefit in improving body composition.Trial registrationClinicalTrials.gov: NCT01909440. Registered 24 July 2013.

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This kindred manifested an X-linked recessive nephrolithiasis with renal failure, a new form of hereditary renal disease. Most of the identifiable physiologic abnormalities occurred after the development of nephrolithiasis and renal insufficiency and may not be of pathogenetic importance.