Physical Exercise Decreases Fasting Hyperglycemia in Diabetic Mice Through AMPK Activation

Introduction: The deficiency in glucose uptake in peripheral tissues and increased hepatic gluconeogenesis are physiopathological phenomena observed in type 2 diabetes patients. Physical exercise plays an important role in the improvement of glycemic profile in diabetic patients; however, the mechanisms involved in these processes have not been fully elucidated. Objective: to assess the role of AMPK protein in the glycemic control of diabetic mice after exercise. Methods: During fasting condition, the insulin tolerance test (ITT) and Western blot technique, were combined to assess the glucose homeostasis in diabetic mice (ob/ob and db/db) after a single swimming session. Results: Fasting hyperglycemia, severe insulin resistance and deficiency in the AMPk/ACC signaling in muscle and liver observed in the diabetic mice were reversed after the exercise session. The restoration of AMPK/ACC signaling reduced the expression of the gluconeogenic enzyme, PEPCk in the liver, and increased the translocation of GLUT4 in the skeletal muscle. These data indicate that the activation of AMPK/ACC pathway induced by physical exercise is important to reduce fasting glucose levels in experimental models of type 2 diabetes. These data open new insights for determination of physical activity control on the glucose homeostasis in diabetic patients.15317918

The Brazilian Longitudinal Study of Aging (ELSI-Brazil): Objectives and Design

Brazil is experiencing among the world’s fastest demographic aging worldwide. This demographic transition is occurring in a context of few resources and great social inequalities. The Brazilian Longitudinal Study of Aging (ELSI-Brazil) is a nationally representative study of 9,412 people aged 50 years or older, residing in 70 municipalities across the 5 Brazilian regions. ELSI-Brazil allows investigations of the aging process, its health, psychosocial and economic determinants, and societal consequences. The baseline examination (2015–2016) included detailed household and individual interviews and physical measurements (blood pressure, anthropometry, grip strength, and timed walk and balance tests). Blood tests and sample storage were performed in a subsample of study participants. Subsequent waves are planned for every 3 years. The study adopts a conceptual framework common to other large-scale longitudinal studies of aging in the world, such as the Health and Retirement Study, allowing cross-national comparisons. The goal of ELSI-Brazil is not only to build an understanding of aging in a large, Western, middle-income country in a rapid demographic transition but also to provide scientific data to support and study policy changes that may affect older adults. We describe the methodology of the study and some descriptive results of the baseline survey

The short-term effect of high versus moderate protein intake on recovery after strength training in resistance-trained individuals

Background: Dietary protein intakes up to 2.9 g.kg-1.d-1 and protein consumption before and after resistance training may enhance recovery, resulting in hypertrophy and strength gains. However, it remains unclear whether protein quantity or nutrient timing is central to positive adaptations. This study investigated the effect of total dietary protein content, whilst controlling for protein timing, on recovery in resistance trainees. Methods: Fourteen resistance-trained individuals underwent two 10-day isocaloric dietary regimes with a protein content of 1.8 g.kg-1.d-1 (PROMOD) or 2.9 g.kg-1.d-1 (PROHIGH) in a randomised, counterbalanced, crossover design. On days 8-10 (T1-T3), participants undertook resistance exercise under controlled conditions, performing 3 sets of squat, bench press and bent-over rows at 80% 1 repetition maximum until volitional exhaustion. Additionally, participants consumed a 0.4 g.kg-1 whey protein concentrate/isolate mix 30 minutes before and after exercise sessions to standardise protein timing specific to training. Recovery was assessed via daily repetition performance, muscle soreness, bioelectrical impedance phase angle, plasma creatine kinase (CK) and tumor necrosis factor-α (TNF-α). Results: No significant differences were reported between conditions for any of the performance repetition count variables (p>0.05). However, within PROMOD only, squat performance total repetition count was significantly lower at T3 (19.7 ± 6.8) compared to T1 (23.0 ± 7.5; p=0.006). Pre and post-exercise CK concentrations significantly increased across test days (p≤0.003), although no differences were reported between conditions. No differences for TNF-α or muscle soreness were reported between dietary conditions. Phase angle was significantly greater at T3 for PROHIGH (8.26 ± 0.82°) compared with PROMOD (8.08 ± 0.80°; p=0.012). Conclusions: When energy intake and peri-exercise protein intake was controlled for, a short term PROHIGH diet did not improve markers of muscle damage or soreness in comparison to a PROMOD approach following repeated days of intensive training. Whilst it is therefore likely that protein intakes (1.8g.kg-1.d-1) may be sufficient for resistance-trained individuals, it is noteworthy that both lower body exercise performance and bioelectrical phase angle were maintained with PROHIGH. Longer term interventions are warranted to determine whether PROMOD intakes are sufficient during prolonged training periods or when extensive exercise (e.g. training twice daily) is undertaken