ABSTRACT
This study described 1-year changes in body weight and metabolic syndrome components in middle-aged obese Japanese men participating in a 6-month weight loss program. This study comprised two phases: 6-month weight loss program and 12-month weight maintenance. Data were collected at Tsukuba, between July 2009 and February 2011. Overweight or obese Japanese men aged 40-64 years without any cardiovascular disease history participated. The primary outcome was the 18-month weight change. Secondary outcomes were 18-month changes in metabolic syndrome components. Primary analyses included all participants who had provided baseline data, and all missing follow-up values were replaced with their baseline data. Of the 58 participants, 39 (67.2%) completed all measurement visits. Their body weight decreased significantly immediately after the 6-month weight loss program (-8.0 kg; 95% confidence interval [CI]: -10.2 kg, -5.8 kg). However, it increased significantly, by 3.7 kg (95% CI: 1.4 kg, 6.0 kg), at Month 18 (a year after the program ended). The 18-month weight loss was 4.3 kg (95% CI: 2.1 kg, 6.5 kg). Among the metabolic syndrome components, visceral fat area, systolic blood pressure, and high-density lipoprotein cholesterol levels improved significantly at Month 18. The other components did not improve over the 18 months. In this study, the obese, middle-aged Japanese men experienced modest weight regains after its substantial reduction. Unlike other ethnicities, factors associated with long-term weight loss maintenance remain understudied among Japanese adults. Therefore, accumulating evidence from Japanese studies with longer follow-up is necessary in the future.
ABSTRACT
We clarify the effect of combination of low-carbohydrate diet and resistance exercise training on physical characteristics and plasma concentrations of metabolites and hormones in humans. Intervention of low-carbohydrate diet and resistance exercise training were performed on 7 healthy men and 3 women (age 39.6 ± 7.0 year; BMI 25.1 ± 3.6 kg/m2) for 8 - 12 weeks. Physical characteristics and 106 test items including and blood concentrations of metabolites and hormones were measured before and after the intervention. The effects of intervention were analyzed by a paired t-test, in which multiple testing was corrected by the method of Storey (significant variation q <0.1). In both men and women, carbohydrate and energy intake per day were low, and protein intake per day was almost the same as the recommended dietary allowance. Because carbohydrate intake were limited (174 kcal), resulting in reduction of total energy (1186 kcal). After the intervention, body weight, BMI (Body Mass Index), fat mass, body fat, muscle mass and body water content significantly decreased, while muscle mass per body mass significantly increased. Glycine, 3-methyl histidine, inorganic phosphorous, urea nitrogen, urea nitrogen per creatinine, were significantly increased, while HbA1c, white blood cell count, β-aminoisobutyric acid, adrenalin, free T4, blood ammonia, γGTP, cholinesterase, and leptin were decreased.