Examining the mediating role of muscle quantity in adolescents: associations with adiposity, cardiorespiratory fitness, muscular fitness, and cardiometabolic risk factors.

The aim of this study was to evaluate the mediation role of muscle quantity in the relationship between physical fitness and cardiometabolic risk factors (CMRF) in adolescents. This cross-sectional study conducted with 120 adolescents of both sexes, aged between 10 and 17 years. Body mass, height, fat mass (FM), lean mass, blood pressure, high-density lipoprotein, low-density lipoprotein, triglycerides, glucose, insulin, cardiorespiratory fitness (CRF) and 1 repetition maximum strength (1-RM) with evaluation of the leg press 45° (RM-leg), bench press (RM-bench) and arm curl (RM-arm). Body mass index z-score, appendicular skeletal muscle mass, appendicular skeletal muscle mass index, lean mass index (LMI), muscle-to-fat ratio (MFR), age at peak height velocity, and CMRF z-score were calculated. The direct relation between FM and CMRF was mediated by the LMI (26%) and inverse relation between CRF and CMRF was mediated by the LMI (26%). For girls, the direct relation between FM and CMRF was mediated by the LMI (32%); the inverse relation between CRF, RM-leg, RM-arm and CMRF was mediated by the LMI (32%, 33%, and 32%, respective). For boys, the indirect effect was not significant, indicating that LMI is not a mediator in the relation between FM, CRF, 1-RM with CMRF. The direct relation between RM-leg and CMRF was mediated by the MRF (16%). This finding evidenced the importance of promoting a healthy lifestyle to improve physical fitness levels and the quantity of muscle mass in adolescents.

Relationship between postural changes, osteoarthritis and bone mineral density in postmenopausal women.

OBJECTIVES: To assess the relationship between postural changes, osteoarthritis (OA) and bone mineral density (BMD) in postmenopausal women. METHODS: A total of 127 Brazilian women, aged 45 years or older, were included in this retrospective study. Subjects were divided in two groups: study group with postural changes (SG) and control group without postural changes (CG). Possible postural changes considered were scoliosis, kyphosis and lordosis. All women underwent BMD assessment and OA was identified at the region of the hip and lumbar spine by dual energy X-ray absorptiometry (DXA) analysis. RESULTS: SG was older (66.0 ± 7.3 years) than the CG (61.0 ± 8.6 years). In the entire sample we found thirteen women with OA and low BMD. Overall, the lumbar spine area was more affected by OA than the hip. The value of BMD T-score accounted for up to 77% of the changes observed in the SG group. CONCLUSION: Postural changes identified in women are directly related to aging and associated with bone loss and joint degeneration. Postural changes may be the primary sign of frailty as a result of body adaptation to pain related to musculoskeletal diseases.

Lean mass and strength profile of women submitted to bariatric surgery: comparison of the EWGSOP2 and FNIH classification for sarcopenia - ASBS program phase II.

Aim: To assess the effect of bariatric surgery on the lean mass of women after one year of the procedure, comparing its outcomes upon the classification from both the Foundation of the National Institutes of Health (FNIH) and the European Working Group on Sarcopenia in the Elderly People (EWGSOP). Material and methods: Twenty-eight obese women aged 40.5 ± 9.8 yrs who underwent Roux-en-Y gastric bypass (RYGB) were included. 27 of them were reassessed after 6 months of surgery, and 16 completed the one-year follow-up. Pre-sarcopenia condition was assessed through a handgrip strength test and body composition by dual-energy X-ray absorptiometry (DXA). Total body mass, body mass index, and lean mass (LM) were collected prior to, 6 and 12 months after RYGB surgery. Results: All subjects reassessed after 12 months were diagnosed with pre-sarcopenia according to the FNIH classification criteria, while according to the EWGSOP2 Consensus they presented normal values. LM represented 14% of the influence on handgrip strength (p = .049) after 6 months of surgery; however, its influence on strength after 12 months increased to 30% (p = .028). Conclusion: The FNIH classification is the most effective criteria since it uses LM content as the first test, considering that strength capacity needs more time to be affected by the surgical procedure. On the other hand, the EWGSOP2 classification should not be applied to determine the loss of LM in younger populations regardless of what may have caused such changes.

Effect of specific exercise training on bone mineral density in women with postmenopausal osteopenia or osteoporosis.

AIM: To analyse the effect of a specific program of weight training exercise with closed kinetic chain in bone mineral density in postmenopausal women with osteopenia or osteoporosis. METHODS: A total of 59 postmenopausal women with osteoporosis or osteopenia were included in this prospective study. Subjects were divided into two groups: the study group (SG, n = 30; 57.5 + or - 5.1 years) and the control group (CG, n = 29; 56.6 + or - 4.6 years). In the study group was applied a weight exercise protocol (longitudinal forces in closed kinetic chain) during 12 months, whereas in the control group no weight exercise protocol was applied. Bone mineral density at the lumbar spine and hip was assessed at baseline and at the end of follow-up by dual energy X-ray absorptiometry. RESULTS. Although no significant intragroup differences were found, patients in SG showed a 1.17% increase in the lumbar spine whereas in CG a 2.26% decrease in bone density was detected. CONCLUSION: This protocol of weight training exercise did not significantly improve bone mineral density in postmenopausal women with osteopenia or osteoporosis, but in comparison to the control group, the results showed the importance of practising the specific exercise program for maintenance of bone health in postmenopausal women.