No abstract

Whole-body vibration is reported to increase muscle performance, bone mineral density and stimulate the secretion of lipolytic and protein anabolic hormones, such as GH and testosterone, that might be used for the treatment of obesity. To date, as no controlled trial has examined the effects of vibration exercise on the human endocrine system, we performed a randomized controlled study, to establish whether the circulating concentrations of glucose and hormones (insulin, glucagon, cortisol, epinephrine, norepinephrine, GH, IGF-1, free and total testosterone) are affected by vibration in 10 healthy men [age 39 +/- 3, body mass index (BMI) of 23.5 +/- 0.5 kg/m2, mean +/- SEM]. Volunteers were studied on two occasions before and after standing for 25 min on a ground plate in the absence (control) or in the presence (vibration) of 30 Hz whole body vibration. Vibration slightly reduced plasma glucose (30 min: vibration 4.59 +/- 0.21, control 4.74 +/- 0.22 mM, p=0.049) and increased plasma norepinephrine concentrations (60 min: vibration 1.29 +/- 0.18, control 1.01 +/- 0.07 nM, p=0.038), but did not change the circulating concentrations of other hormones. These results demonstrate that vibration exercise transiently reduces plasma glucose, possibly by increasing glucose utilization by contracting muscles. Since hormonal responses, with the exception of norepinephrine, are not affected by acute vibration exposure, this type of exercise is not expected to reduce fat mass in obese subjects.

OBJECTIVE -To establish the impact of different amounts of increased energy expenditure on type 2 diabetes care. RESEARCH DESIGN AND METHODS-Post hoc analysis of long-term effects of different amounts of increased energy expenditure (metabolic equivalents [METS] per hour per week) through voluntary aerobic physical activity was performed in 179 type 2 diabetic subjects (age 62 Ϯ 1 years [mean Ϯ SE]) randomized to a physical activity counseling intervention. Subjects were followed for 2 years and divided into six groups based on their increments in METs per hour per week: group 0 (no activity, n ϭ 28), group 1-10 (6.8 Ϯ 0.3, n ϭ 27), group 11-20 (17.1 Ϯ 0.4, n ϭ 31), group 21-30 (27.0 Ϯ 0.5, n ϭ 27), group 31-40 (37.5 Ϯ 0.5, n ϭ 32), and group Ͼ40 (58.3 Ϯ 1.8, n ϭ 34).RESULTS -At baseline, the six groups did not differ for energy expenditure, age, sex, diabetes duration, and all parameters measured. After 2 years, in group 0 and in group 1-10, no parameter changed; in groups [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40] and Ͼ40, HbA 1c , blood pressure, total serum cholesterol, triglycerides, and estimated percent of 10-year coronary heart disease risk improved (P Ͻ 0.05). In group 21-30, 31-40, and Ͼ40, body weight, waist circumference, heart rate, fasting plasma glucose, serum LDL and HDL cholesterol also improved (P Ͻ 0.05). METs per hour per week correlated positively with changes of HDL cholesterol and negatively with those of other parameters (P Ͻ 0.001). After 2 years, per capita yearly costs of medications increased (P ϭ 0.008) by $393 in group 0, did not significantly change in group 1-10 ($206, P ϭ 0.09), and decreased in group 11-20 (Ϫ$196, P ϭ 0.01), group 21-30 (Ϫ$593, P ϭ 0.009), group 31-40 (Ϫ$660, P ϭ 0.003), and group Ͼ40 (Ϫ$579, P ϭ 0.001). CONCLUSIONS -Energy expenditure Ͼ10METs ⅐ h Ϫ1 ⅐ week Ϫ1 obtained through aerobic leisure time physical activity is sufficient to achieve health and financial advantages, but full benefits are achieved with energy expenditure Ͼ20 METs ⅐ h Ϫ1 ⅐ week Ϫ1 . Diabetes Care 28:1295-1302, 2005W estern and developing countries face two serious health problems: the rising prevalence of obesity and diabetes and the fact that people no longer need to be physically active in their daily lives (1-4). Many studies have shown that regular physical activity improves quality of life, reduces the risk of mortality from all causes (1-4), and is particularly advantageous in subjects with impaired glucose tolerance (5,6) or type 2 diabetes (7-12). Physical activity counseling can motivate most diabetic subjects to increase their levels of voluntary energy expenditure (9 -11), but, at present, the relationship between amounts of physical activity and longterm beneficial effects in type 2 diabetes care is unknown. The American Diabetes Association emphasizes the benefits of regular physical activity in the prevention and treatment of type 2 diabetes, referring to proposals given to the general population by...

Aging is associated with a progressive loss of bone-muscle mass and strength. When the decline in mass and strength reaches critical thresholds associated with adverse health outcomes, they are operationally considered geriatric conditions and named, respectively, osteoporosis and sarcopenia. Osteoporosis and sarcopenia share many of the same risk factors and both directly or indirectly cause higher risk of mobility limitations, falls, fractures and disability in activities of daily living. This is not surprising since bones adapt their morphology and strength to the long-term loads exerted by muscle during anti-gravitational and physical activities. Non-mechanical systemic and local factors also modulate the mechanostat effect of muscle on bone by affecting the bidirectional osteocyte-muscle crosstalk, but the specific pathways that regulate these homeostatic mechanisms are not fully understood. More research is required to reach a consensus on cut points in bone and muscle parameters that identify individuals at high risk for adverse health outcomes, including falls, fractures and disability. A better understanding of the muscle-bone physiological interaction may help to develop preventive strategies that reduce the burden of musculoskeletal diseases, the consequent disability in older persons and to limit the financial burden associated with such conditions. In this review, we summarize age-related bone-muscle changes focusing on the biomechanical and homeostatic mechanisms that explain bone-muscle interaction and we speculate about possible pathological events that occur when these mechanisms become impaired. We also report some recent definitions of osteoporosis and sarcopenia that have emerged in the literature and their implications in clinical practice. Finally, we outline the current evidence for the efficacy of available anti-osteoporotic and proposed anti-sarcopenic interventions in older persons.

This randomized controlled study was designed to test the efficacy and safety of percutaneous ultrasound (US)-guided laser photocoagulation (PLP) for treatment of subjects with compressive symptoms due to benign thyroid nodules and/or at high surgical risk. Twenty six subjects were randomized to the intervention (no. 13, age 68+/-3 yr, mean+/-SEM) or observation (no. 13, age 71+/-2 yr) groups. In the control group, the volume of nodules did not significantly change over the 30 week period of observation. In the intervention group, median nodule volume at baseline was 8.2 ml (range 2.8-26.9) and was not significantly different from that of the control group. Nodules decreased significantly (p<0.0001) by 22% after 2 weeks (6.5 ml; range 2.4-16.7) and by 44% after 30 weeks (4.6 ml; range 0.69-14.2). Energy given was correlated (p<0.05) with the reduction of thyroid nodule volume. All patients tolerated the treatment well and reported relief from compressive and cosmetic complaints (p<0.05). At the time of enrolment 7/13 (54%) and 6/13 (46%) of patients in the intervention and control groups, respectively, had sub clinical hyperthyroidism. PLP normalized thyroid function at 6 and 30 weeks after treatment. In conclusion, PLP is a promising safe and effective procedure for treatment of benign thyroid nodules in patients at high surgical risk.