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.

Objectives The objectives of the present study were to translate the English version of the Pregnancy Physical Activity Questionnaire into Chinese (PPAQ-C) and to determine its reliability and validity for use by pregnant Chinese women. Methods The study included 224 pregnant women during their first, second, or third trimesters of pregnancy who completed the PPAQ-C on their first visit and wore a uniaxial accelerometer (Lifecorder; Suzuken Co. Ltd) for 7 days. One week after the first visit, we collected the data from the uniaxial accelerometer records, and the women were asked to complete the PPAQ-C again. Results We used intraclass correlation coefficients to determine the reliability of the PPAQ-C. The intraclass correlation coefficients were 0.77 for total activity (light and above), 0.76 for sedentary activity, 0.75 for light activity, 0.59 for moderate activity, and 0.28 for vigorous activity. The intraclass correlation coefficients were 0.74 for "household and caregiving", 0.75 for "occupational" activities, and 0.34 for "sports/exercise". Validity between the PPAQ-C and accelerometer data was determined by Spearman correlation coefficients. Although there were no significant correlations for moderate activity (r = 0.19, P > 0.05) or vigorous activity (r = 0.15, P > 0.05), there were significant correlations for total activity [light and above; r = 0.35, P < 0.01)] and for light activity (r = 0.33, P < 0.01). Conclusions for Practice The PPAQ-C is reliable and moderately accurate for measuring physical activity in pregnant Chinese women.

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...

Background Physical activity (PA) and dietary intake are important modifiable factors associated with health outcomes. However, Chinese pregnant women’s PA and dietary intake are only vaguely understood. The aim of this study was to reveal the characteristics of PA and dietary intake of Chinese women in different trimesters as well as the associations between PA and dietary intake. Methods This is a cross-sectional observational study. PA, dietary intake, and demographics of 1077 Chinese pregnant women were measured. The Chi-square test, Kruskal-Wallis test, multiple logistic regression, and multiple linear regression were used for data analysis. Results About 57.1% of the participants met the international guideline for PA. Household activity and occupational activity contributed the most to the total PA, while sports/exercise contributed little. The mean energy intake of the participants was 2008 ± 748.0 kcal. Most participants had normal energy intake, but they obtained excessive energy from fat (mean = 41.7 ± 8.7%). PA was not found to be significantly associated with dietary intake. Further, the participants who were unemployed during pregnancy (OR = 0.72, 95% CI: 0.55–0.95; p < 0.05) or had no exercise habits before pregnancy (OR = 0.62, 95% CI: 0.47–0.80; p < 0.01) were less likely to meet the PA guideline. The participants in the third trimester (OR = 1.43, 95% CI: 1.03–1.99; p < 0.05) were more likely to meet the PA guideline compared to those in the first trimester. The older participants (> 30 years) showed higher dietary intake than the younger (< 25 years) participants ( p < 0.01). Conclusions The total PA of Chinese women during pregnancy mostly consists of household and occupational activities, but little sports/exercise. Starting exercise before pregnancy may help women achieve adequate PA during pregnancy. Moreover, these women consumed an excessive amount of fat and their diet intake varies by age.

Maximal fat oxidation (MFO) rate and the exercise intensity that elicits MFO (FATmax-intensity) were designed to evaluate fat metabolism capacity and to provide individuals with a target exercise intensity during prolonged exercise. However, the previous methods of determining FATmax-intensity were time-consuming. The purpose of this study was to examine the validity of FATmax-intensity determined by short-time testing. Nine healthy young men performed ramp exercise, in a short-time test, until exhaustion and 5 constant-load exercises of 60 min each at individual FATmax-intensity determined by ramp protocol (FATmax-intensity(R)), FATmax-intensity(R) ± 5% of peak oxygen uptake (VO₂peak) and FATmax-intensity(R) ± 10%VO₂peak. FATmax-intensity was determined among 5 trials at points of early exercise (10 min) and prolonged exercise (60 min) to evaluate the validity of FATmax-intensity(R). Ten minutes after starting constant-load exercise, FATmax-intensity(R) showed the highest fat oxidation among 5 trials, even though MFO by ramp protocol was overestimated. Therefore, it may be useful for evaluation of fat metabolism to include the measurement of the FATmax-intensity in a routine ramp test. However, because FATmax-intensity(R) did not elicit the highest fat oxidation among 5 trials of 60 min each after starting constant-load exercise, FATmax-intensity(R) may not be effective for prolonged exercise training.

No abstract

The effects of Chios mastic gum () and exercise on physical characteristics, blood lipid markers, insulin resistance, and hepatic function were investigated in healthy, non-smoking Japanese men aged ≥ 40 years. Participants were allocated to control (C, 5 g/day placebo powder, n = 7), mastic (M, 5 g/day mastic powder, n = 7), or mastic plus physical activity groups (M + PA, 5 g/day mastic powder and 30-min exercise three times/week, n = 7), and measurements were taken at baseline, 3 and 6 months. Serum triglycerides were significantly reduced at 3 months in M and M + PA compared with C ( < 0.05). Serum insulin and homeostatic model assessment of insulin resistance values were significantly reduced at 3 and 6 months in M + PA, and at 6 months in M, compared with C ( < 0.05). These results indicate that Chios mastic gum intake for 6 months reduced serum triglyceride and insulin concentrations, and additional exercise enhanced the effect on insulin.

The aim of this study was to investigate the effects of sleep deprivation on autonomic and endocrine functions during the day and on exercise tolerance in the evening. Ten healthy young males completed two, 2-day control and sleep deprivation trials. For the control trial, participants were allowed normal sleep from 23:00 to 07:00 h. For the sleep deprivation trial, participants did not sleep for 34 h. Autonomic activity was measured from 19:00 h on day 1 to 16:00 h on day 2 by frequency-domain measures of heart rate variability. Endocrine function was examined by measuring adrenocorticotropic hormone and cortisol from venous blood samples collected on day 2 at 09:00, 13:00, and 17:00 h and immediately after an exercise tolerance testing. Autonomic regulation, particularly parasympathetic regulation estimated from the high-frequency component of heart rate variability analysis, was significantly higher in the sleep deprivation trial than in the control trial in the morning and afternoon of day 2. Plasma adrenocorticotropic hormone concentrations were significantly higher at 09:00 and 13:00 h of day 2 under sleep deprivation. Heart rate during exercise was significantly lower following sleep deprivation. Therefore, the effects of sleep deprivation on autonomic regulation depend on the time of the day.