Effect of strength training and short-term detraining on muscle mass in women aged over 50 years old

The loss of muscle mass is associated with aging. The aim of this study was to determine the effects of resistance training and detraining on muscle mass in elderly women. Twenty post-menopausal women aged >/= 50 years old were enrolled. Matching for age, they were randomly assigned into control and resistance training group [RT]. The intervention consisted of three sets of 10 repetitions for 10 movements with Thera-Band tubing [based on 80-100% 10-RM], three times a week, for 12 weeks and thereafter, four weeks detraining. Skinfold thickness was determined by caliper. Percentage of body fat was estimated from skinfold thickness [triceps and subscapular] by McArdle method. Fat mass [FM] and fat-free mass [FFM] were calculated. Range of motion for trunk flexion and extension was determined. During 12 weeks of intervention, significant increases were observed in 1-RM of biceps curl, FFM, trunk flexion and extension and significant decreases during four weeks detraining in RT group. The RT group demonstrated significant decreases during resistance training and increases during detraining in skinfold thickness. FFM, trunk flexion, and extension decreased and skinfold thickness,%FM, and weight of body fat increased in the control group [P < 0.05]. Resistance training with Thera-Band enhanced strength and muscle endurance in elderly women and a 4-week detraining period had an adverse effect on muscle power. This suggests that a strength training program is an effective intervention to prevent functional reductions, and can contribute to improve neuromuscular function in older adults

Diagnostic values of metabolic syndrome definitions for detection of insulin resistance: Tehran lipid and glucose study [TLGS]

This study examines the characteristics and agreement between different definitions of metabolic syndrome [MetS] and insulin resistance [IR]. A total of 347 non-diabetic individuals who were >/= 20 years of age were selected from the Tehran Lipid and Glucose Study [TLGS]. Subjects were categorized as having MetS by the Adult Treatment Panel III [ATP III] and the Joint Interim Statement [JIS]. IR was estimated by using the homeostasis model assessment [HOMA-IR]. According to ATP III and JIS criteria 38.9% and 38.2% of subjects had MetS respectively. The sensitivity of ATP III was 52.3% and specificity was 65%; for JIS the sensitivity was 52.3%, with a specificity of 66.5%. Kappa between ATP III or JIS and HOMA-IR was 0.14 and 0.16, respectively. Based on receiver operating characteristic [ROC] analysis, the use of waist circumference [WC] and fasting plasma glucose [FPG] for the diagnosis of IR in women showed a diagnostic accuracy equal to or instead of counting MetS components using modified ATP III or JIS. WC optimal cut points for prediction of IR were 93.5 cm for men and 92.5 cm for women. ATP III and JIS definitions have low sensitivities and specificities for detecting IR. There is poor agreement between these criteria and IR