PurposeTo compare the effects of endurance exercise performed in the morning and evening on inflammatory cytokine responses in young men.MethodsFourteen healthy male participants aged 24.3 ± 0.8 years (mean ± standard error) performed endurance exercise in the morning (0900–1000 h) on one day and then in the evening (1700–1800 h) on another day with an interval of at least 1 week between each trial. In both the morning and evening trials, the participants walked for 60 minutes at approximately 60% of the maximal oxygen uptake () on a treadmill. Blood samples were collected to determine hormones and inflammatory cytokines at pre-exercise, immediately post exercise, and 2 h post exercise.ResultsPlasma interleukin (IL)-6 and adrenaline concentrations were significantly higher immediately after exercise in the evening trial than in the morning trial (P < 0.01, both). Serum free fatty acids concentrations were significantly higher in the evening trial than in the morning trial at 2 h after exercise (P < 0.05). Furthermore, a significant correlation was observed between the levels of IL-6 immediately post-exercise and free fatty acids 2 h post-exercise in the evening (r = 0.68, P < 0.01).ConclusionsThese findings suggest that the effect of acute endurance exercise in the evening enhances the plasma IL-6 and adrenaline concentrations compared to that in the morning. In addition, IL-6 was involved in increasing free fatty acids, suggesting that the evening is more effective for exercise-induced lipolysis compared with the morning.

BACKGROUND/OBJECTIVES: Postprandial hyperglycemia increases the risks of development of type 2 diabetes and cardiovascular diseases. The purpose of this study was to determine whether a 3-day low-carbohydrate/high-fat diet (LC/HFD) alters postprandial plasma glucose and incretin levels during oral glucose tolerance test (OGTT) in healthy men. SUBJECTS/METHODS: Nine healthy young men (age (mean±s.e.), 27±1 years; body mass index, 22±1 kg/m 2 ) consumed either a normal diet (ND: energy from B22% fat) or a LC/HFD (energy from B69% fat) for 3 days each. The total energy intake from each diet was similar. An OGTT was performed after each 3-day dietary intervention. Postprandial plasma glucose, insulin, free fatty acid and glucagon-like peptide-1 (GLP-1) levels were determined at rest and during the OGTT. RESULTS: Plasma glucose levels and incremental area under the curve during the OGTT were significantly higher in the LC/HFD trial than in the ND trial (P ¼ 0.024). In addition, increase in GLP-1 levels was significantly higher in the LC/HFD trial than in the ND trial (P ¼ 0.025). The first-phase insulin secretion indexes were significantly lower in the LC/HFD trial than in the ND trial (Po0.041).CONCLUSIONS: These results demonstrate that even short-term LC/HFD increased postprandial plasma glucose and GLP-1 levels in healthy young men. A decrease in first-phase insulin secretion may partially contribute to the short-term LC/HFD-induced increase in postprandial plasma glucose levels. Keywords: postprandial hyperglycemia; incretin; impaired glucose tolerance; glucose-dependent insulinotropic polypeptide INTRODUCTION Postprandial hyperglycemia is a condition of high blood glucose level after eating a meal, and is an effective predictor of mortality from all causes and cardiovascular diseases (CVD) as well as the risk of developing type 2 diabetes.1-3 Furthermore, decreasing postprandial hyperglycemia with medications reduces the risks of developing CVD and type 2 diabetes. [4][5][6] One of the factors explaining the association between postprandial hyperglycemia and the development of CVD and type 2 diabetes is the resulting acute fluctuation in blood glucose levels. Interestingly, acute fluctuation in blood glucose levels suppresses endotheliumdependent vasodilation, 7 and increases levels of interleukin-6, tumor necrosis factor-a 8 and platelet hyperaggregability 9 in healthy men; all these parameters have been associated with the development of CVD. Therefore, it is important to elucidate the factors that elicit postprandial hyperglycemia for the prevention of both CVD and type 2 diabetes.A low-carbohydrate/high-fat diet (LC/HFD) has a key role in the development of postprandial hyperglycemia. Short-term exposure (1-11 days) to LC/HFD decreases carbohydrate oxidation 10-16 and increases endogenous glucose production. 10,17 In addition, shortterm LC/HFD (3-5 days) decreases insulin sensitivity, as measured using the hyperinsulinemic-euglycemic glucose clamp 18,19 and the intravenous glucose tolerance test. 20 However...

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OKURA, TOMOHIRO, YOSHIO NAKATA, KAZUNORI OHKAWARA, SHIGEHARU NUMAO, YASUTOMI KATAYAMA, TOMOAKI MATSUO, AND KIYOJI TANAKA. Effects of aerobic exercise on metabolic syndrome improvement in response to weight reduction. Obesity. 2007;15:2478 -2484. Objective: The objective was to test effects of aerobic exercise training on metabolic syndrome (MetSyn) improvement in response to weight reduction. Research Methods and Procedures: A total of 459 overweight and obese women (age, 49 Ϯ 9 years; BMI, 28 Ϯ 3 kg/m 2 ) were recruited for a baseline examination to test the relationship between cardiorespiratory fitness and metabolic syndrome prevalence; among these, 67 subjects with MetSyn were treated with 14-week weight-loss programs, which included low-calorie diet and aerobic exercise. The MetSyn was defined according to the Examination Committee of Criteria for "Metabolic Syndrome" in Japan. Maximal oxygen uptake (V O 2max ) during a maximal cycling test was measured as an index of cardiorespiratory fitness at baseline and after the intervention. Results: In the baseline examination, age-and BMI-adjusted odds ratios for MetSyn prevalence in the low, middle, and upper thirds of V O 2max were 1.0 (referent), 0.50 (95% confidence interval, 0.26 to 0.95), and 0.39 (95% confidence interval, 0.14 to 0.96), respectively (linear trend, p ϭ 0.02). The adjusted odds ratios for MetSyn improvement in the two interventions with diet alone and diet plus exercise were 1.0 and 3.68 (95% confidence interval, 1.02 to 17.6; p ϭ 0.04), respectively. Discussion: These results suggest that adding aerobic exercise training to a dietary weight-reduction program further improves MetSyn (adjusted odds ratio, 3.68) in obese women, compared with diet alone. Further studies on an association between V O 2max change and MetSyn improvement are needed.

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Objectives: It is well known that body weight loss through a direct (supervised) lifestyle intervention (LSI) improves obesityrelated metabolic disorders. The purpose of this study was to investigate the effects of an indirect LSI on weight loss and metabolic syndrome (MetS) in spouses of LSI participants. Methods: A total of 104 men (abdominal circumference X85 cm; age, 52.1 ± 9.3 years) were assigned to one of three groups: no intervention (NI, n ¼ 34), direct intervention (DI, n ¼ 34) or indirect intervention (II, n ¼ 36), the last of which consisted of subjects who did not participate in the direct LSI but whose wives did. Body weight and MetS components were measured before and after a 14-week intervention. Daily energy intake and activity-related energy expenditure were assessed before and during the intervention. The LSI program was mainly consisted of dietary modifications with a physical activity program. Results: No differences were observed across the three groups in any of the measures at baseline. Significant differences were observed among the groups in weight loss (NI, À0.7 ± 1.4; DI, À6.2 ± 3.3 and II, À4.4 ± 3.7 kg) during the intervention. Along with the body weight reductions, significant improvements were observed in most of MetS components within the DI and II groups. When analyzing the spouse pairs in group II, significant correlations were observed in weight loss (r ¼ 0.57) and decreased total energy intake (r ¼ 0.54) between wives and husbands. Conclusions: Indirect LSI in abdominally obese men whose wives were undergoing LSI led to loss of weight and a decreased incidence of MetS, suggesting that indirect LSI may be an effective program for eliciting beneficial change in health status. one spouse has a significant impact on weight loss in the untreated spouse. They clearly showed 'a ripple effect' on weight loss through spouses. However, the studies did not include examinations of MetS components, which can be greatly affected by changes in body adiposity. To the best of our knowledge, the study by Sexton et al. 17 is the only one to show that a health behavior intervention for one spouse has a ripple effect on cardiovascular risk factors in the other, untreated spouse. Although the study focused on three cardiovascular risk factors (blood pressure, cigarette smoking and serum cholesterol) it did not examine subjects' weight loss and MetS components. Thus, none of the earlier studies focused on the effects of an indirect LSI on weight loss and improved MetS components in the untreated spouse. Therefore, in this study, we examined the effects on weight loss and MetS components in abdominally obese Japanese men of an indirect LSI through their wives. The primary hypothesis of our study was that the indirect LSI through wives would affect weight loss and improve the MetS components of the husbands who did not receive the direct LSI. We also had a secondary hypothesis that the weight loss and lifestyle changes of wives would correlate with those of their husbands.

Introduction: The purpose of this study was to investigate the effects of 12-week exercise training on circulating retinol-binding protein 4 (RBP4) concentration and cardiovascular disease (CVD) risk factors in obese men. Methods: 29 obese men (age 48 ± 2 years; BMI 29.6 ± 0.7 kg/m²) participated in a 12-week exercise program (50–70% maximal heart rates; 3 times/week) without calorie restriction. Anthropometric parameters, CVD risk factors (total cholesterol, high-density lipoprotein cholesterol (HDLC), low-density lipoprotein cholesterol, triglycerides (TG), and quantitative insulin sensitivity check index), and circulating RBP4 and adipokine (adiponectin, leptin, and interleukin-6 (IL-6)) concentrations were measured. Results: Exercise training significantly improved in absolute peak oxygen consumption (p < 0.05), and CVD risk factors (p < 0.05), with the exception of HDLC. There was a significant decrease in circulating RBP4, leptin, and IL-6 concentrations (p < 0.05). Stepwise regression analysis revealed that changes in RBP4 concentration were independently related to the changes in TG concentration (β = 0.46, p < 0.05). Conclusion: These results demonstrate that exercise training without calorie restriction improves several CVD risk factors and circulating RBP4 and adipokine concentrations. Moreover, the change in circulating RBP4 may be more associated with the improvements in TG concentration in obese men.

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