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.

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.

No abstract

Purpose This study aimed to test the effects of a circuit training (CT; aerobic + strength training) program, with and without motivational interviewing (MI) behavioral therapy, on reducing adiposity and type 2 diabetes risk factors in Latina teenagers. Methods Thirty-eight Latina adolescents (15.8 ± 1.1 yr) who are overweight/obese were randomly assigned to control (C; n = 12), CT (n = 14), or CT + MI (n = 12). The CT classes were held twice a week (60–90 min) for 16 wk. The CT + MI group also received individual or group MI sessions every other week. The following were measured before and after intervention: strength by one-repetition maximum; cardiorespiratory fitness (V̇O2max) by submaximal treadmill test; physical activity by accelerometry; dietary intake by records; height, weight, waist circumference; total body composition by dual-energy x-ray absorptiometry; visceral adipose tissue, subcutaneous adipose tissue, and hepatic fat fraction by magnetic resonance imaging; and glucose/insulin indices by fasting blood draw. Across-intervention group effects were tested using repeated-measures ANOVA with post hoc pairwise comparisons. Results CT and CT + MI participants, compared with controls, significantly increased fitness (+16% and +15% vs −6%, P = 0.03) and leg press (+40% vs +20%, P = 0.007). Compared with controls, CT participants also decreased waist circumference (−3% vs +3%; P < 0.001), subcutaneous adipose tissue (−10% vs 8%, P = 0.04), visceral adipose tissue (−10% vs +6%, P = 0.05), fasting insulin (−24% vs +6%, P = 0.03), and insulin resistance (−21% vs −4%, P = 0.05). Conclusions CT may be an effective starter program to reduce fat depots and improve insulin resistance in Latino youth who are overweight/obese, whereas the additional MI therapy showed no additive effect on these health outcomes.

Although limited by the lack of a sedentary comparison group, these data suggest that age-related losses in VO2max may not be different from data previously reported for older sedentary adults and that loss in muscle strength and performance with aging is not linear.

We tested the validity and reliability of the BioSpace InBody 320, Omron and Bod-eComm body composition devices in men and women (n 254; 21 -80 years) and boys and girls (n 117; 10-17 years). We analysed percentage body fat (%BF) and compared the results with dual-energy X-ray absorptiometry (DEXA) in adults and compared the results of the InBody with underwater weighing (UW) in children. All body composition devices were correlated (r 0·54 -0·97; P#0·010) to DEXA except the Bod-eComm in women aged 71-80 years (r 0·54; P¼ 0·106). In girls, the InBody %BF was correlated with UW (r 0·79; P#0·010); however, a more moderate correlation (r 0·69; P# 0·010) existed in boys. Bland -Altman plots indicated that all body composition devices underestimated %BF in adults (1·0 -4·8 %) and overestimated %BF in children (0·3 -2·3 %). Lastly, independent t tests revealed that the mean %BF assessed by the Bod-eComm in women (aged 51-60 and 71-80 years) and in the Omron (age 18-35 years) were significantly different compared with DEXA (P#0·010). In men, the Omron (aged 18 -35 years), and the InBody (aged 36-50 years) were significantly different compared with DEXA (P¼0·025; P¼ 0·040 respectively). In addition, independent t tests indicated that the InBody mean %BF in girls aged 10 -17 years was significantly different from UW (P¼ 0·001). Pearson's correlation analyses demonstrated that the Bod-eComm (men and women) and Omron (women) had significant mean differences compared with the reference criterion; therefore, the %BF output from these two devices should be interpreted with caution. The repeatability of each body composition device was supported by small CV (, 3·0 %).Body fat: Bioelectrical impedance: Dual-energy X-ray absorptiometry: Underwater weighing Childhood and adult obesity is an epidemic in the USA (1 -3) and it is important to have valid and reliable tools to assess growth and body composition. It is essential that we develop safe and accurate tools to assess body composition as well as devices that are affordable. Devices that accurately depict body fat percentage (%BF) can be used as a tool to evaluate an individual's weight loss or gain over a period of time. Body composition analysis is important for understanding proportional changes in fat and lean mass for healthy individuals as well as individuals with various health conditions. Over the past several years there has been an increase in the marketing and sales of economical body composition analysers (i.e. bioelectrical impedance devices). Therefore, a greater need has developed to evaluate the accuracy of these body composition devices. In addition, practical indicators of %BF for different age ranges and sex are needed for epidemiological and clinical studies.Traditionally, assessing body composition relied upon the principle of underwater weighing, regarded as the 'gold standard' (4) ; however, technology has improved and various devices have been introduced to evaluate body composition. Dual-energy X-ray absorptiometry (DEXA) has become the preferred met...