Effect of vegetable consumption with chewing on postprandial glucose metabolism in healthy young men: a randomised controlled study.

Although thorough chewing lowers postprandial glucose concentrations, research on the effectiveness of chewing vegetables in different forms on postprandial glucose metabolism remains limited. This study examined the effects of vegetables consumed in solid versus puree forms on postprandial glucose metabolism. Nineteen healthy young men completed two 180-min trials on separate days in a random order: the chewing trial involved the consumption of shredded cabbage with chewing and the non-chewing trial involved the consumption of pureed cabbage without chewing. Energy jelly was consumed immediately after the consumption of shredded or puree cabbage. Blood samples were collected at 0, 30, 45, 60, 90, 120 and 180 min. Circulating concentrations of glucose, insulin, total glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic peptide (GIP) concentrations were measured from the plasma. Although plasma glucose concentrations did not differ between the trials, the plasma insulin and GIP incremental area under the curve values were higher in the chewing than in the non-chewing trial. Postprandial total GLP-1 concentrations were higher in the chewing than in the non-chewing trial at 45, 60 and 90 min. This study demonstrates that consuming shredded cabbage while chewing enhances postprandial incretin secretion but has no effect on postprandial glucose concentration.Trial registration: Clinical trial registration ID.: UMIN000052662, registered 31 October 2023.

Habitual Physical Activity and Dietary Profiles in Older Japanese Males with Normal-Weight Obesity.

Normal-weight obesity is defined as having high body fat but a normal body mass index (BMI). This study examined whether there are differences in habitual physical activity and diet between individuals with normal-weight obesity and obese or non-obesity. This study included 143 males aged 65-75 years, and they were classified into the following three groups according to BMI and visceral fat area (VFA): obese group (n = 27 (BMI: ≥25 kg/m2 and VFA: ≥100 cm2)), normal-weight obese group (n = 35 (BMI: <25 kg/m2 and VFA: ≥100 cm2)) and non-obese group (n = 81 (BMI: <25 kg/m2 and VFA < 100 cm2)). Lowered high-density lipoprotein cholesterol and elevated triglyceride and alanine transaminase were observed in the normal-weight obese group than in the non-obese group (all for p ≤ 0.04, effect size ≥ 0.50). No differences were found in physical activity and dietary habits between non-obese and normal-weight obese groups (all for p > 0.05). Although impaired lipid and liver function parameters were observed in older males with normal-weight obesity compared with older males with non-obesity, physical activity and dietary profiles in themselves were not shown these differences in the present study.

Does butyrylcholinesterase mediate exercise-induced and meal-induced suppression in acylated ghrelin?

Ample evidence supports the notion that an acute bout of aerobic exercise and meal consumption reduces acylated ghrelin concentration. However, the mechanisms by which this exercise- and meal-induced suppression of acylated ghrelin occurs in humans is unknown. This study aimed to examine the concentration of butyrylcholinesterase (BChE), an enzyme responsible for hydrolysing ghrelin and other appetite-related hormones in response to a single bout of running and a standardised meal in young, healthy men. Thirty-three men (aged 23 ± 2 years, mean ± standard deviation) underwent two (exercise and meal conditions) 2-h laboratory-based experiments. In the exercise condition, all participants ran for 30 min at 70% of the maximum oxygen uptake (0930-1000) and rested until 1130. In the meal condition, participants reported to the laboratory at 0930 and rested until 1000. Subsequently, they consumed a standardised meal (1000-1015) and rested until 1130. Blood samples were collected at baseline (0930), 1000, 1030, 1100 and 1130. BChE concentration was not altered in both the exercise and meal conditions (p > 0.05). However, acylated ghrelin was suppressed after exercise (p < 0.05) and meal consumption (p < 0.05). There was no association between the change in BChE concentration and the change in acylated ghrelin before and after exercise (p = 0.571). Although des-acylated ghrelin concentration did not change during exercise (p > 0.05), it decreased after meal consumption (p < 0.05). These findings suggest that BChE may not be involved in the suppression of acylated ghrelin after exercise and meal consumption.

The effects of acute and chronic oral l-arginine supplementation on exercise-induced ammonia accumulation and exercise performance in healthy young men: A randomised, double-blind, cross-over, placebo-controlled trial.

Objective: This study examined the effects of a single and chronic oral intake of l-arginine supplementation on blood ammonia concentration and exercise performance. Methods: Sixteen healthy young men (mean ± standard deviation, 23 ± 3 years) participated in a randomised, double-blind, cross-over, placebo-controlled study. For the acute trials, the participants consumed 200 mL of water containing either l-arginine (5 g) or placebo (dextrin; 5.5 g) and performed cycling exercise at 75% of heart rate reserve for 60 min, followed by a 15-min cycling performance test. For the chronic trials, the participants continued to consume each designated supplement twice a day for another 13 days, and then repeated the same protocol as the acute trials at day 15. After a 14-day washout period, the participants changed the supplement and repeated the same protocol as above. Results: Plasma ammonia concentrations were lower in the chronic arginine trial than those in both acute placebo (mean difference - 4.5 µmol/L) and acute arginine (mean difference - 5.1 µmol/L) trials (p < 0.05). There was no difference in plasma ammonia concentration between the chronic arginine and chronic placebo trials (mean difference - 1.2 µmol/L). No differences were found in mean power output during the performance test between the chronic arginine and chronic placebo trials (mean difference 0.5 W) or between the acute arginine and acute placebo trials (mean difference 0.0 W). Conclusions: An acute and chronic oral intake of l-arginine supplementation did not attenuate exercise-induced increases in ammonia accumulation or had no significant impact on cycling performance.

Postprandial Metabolism and Physical Activity in Asians: A Narrative Review.

The widespread benefits of physical activity in enhancing health and lowering the risk of non-communicable chronic diseases are well established across populations globally. Nevertheless, the prevalence of several lifestyle-related chronic diseases, including cardiovascular disease, varies markedly across countries and ethnicities. Direct ethnic comparative studies on the health benefits of physical activity are sparse and evidence-based physical activity guidelines are not ethnicity-specific. Indeed, physical activity guidelines in some Asian countries were developed primarily based on data from Western populations even though the magnitude of potential benefit may not be the same among different ethnic groups. Unfavorable diurnal perturbations in postprandial triglycerides and glucose are risk factors for cardiovascular disease. This narrative review summarizes differences in these risk factors primarily between individuals of Asian and white European descent but also within different Asian groups. Moreover, the variable effects of physical activity on mitigating risk factors among these ethnic groups are highlighted along with the underlying metabolic and hormonal factors that potentially account for these differences. Future ethnic comparative studies should include investigations in understudied ethnic groups, such as those of East Asian origin, given that the effectiveness of physical activity for ameliorating cardiovascular disease varies even among Asian groups.

Gum chewing while walking increases walking distance and energy expenditure: A randomized, single-blind, controlled, cross-over study.

BACKGROUND/OBJECTIVE: Gum chewing while walking increases walking distance and energy expenditure in middle-aged male and female individuals. This study aimed to examine the effects of gum chewing while walking on walking distance and energy metabolism in male and female individuals of various age groups. METHODS: Fifty participants (25 male and 25 female individuals) aged 22-69 years completed two trials in a random order. In the gum trial, participants walked at a natural pace for 15 min while chewing two gum pellets (1.5 g, 3 kcal per pellet) following a 50-min rest period. In the tablet trial, participants rested for 50 min before walking, and the participants then walked at a natural pace for 15 min after ingesting two pellets of tablet containing the same ingredients with the exception of the gum base. The walking distance, step count, walking speed, stride, heart rate, energy expenditure, and respiratory exchange ratio were measured. RESULTS: Walking distance, step count, walking speed, heart rate, and energy expenditure during walking were significantly higher in the gum trial than in the tablet trial. In participants aged ≥40 years, walking distance, walking speed, stride, heart rate, and energy expenditure during walking were significantly increased during the gum trial compared with those during the tablet trial. CONCLUSION: The study findings demonstrated that gum chewing while walking increased walking distance and energy expenditure in both male and female individuals.

The chronic effect of physical activity on postprandial triglycerides in postmenopausal women: A randomized controlled study.

OBJECTIVE: This study examined the chronic effect of increased physical activity on postprandial triglycerides in older women. METHODS: Twenty-six women, aged 72 ± 5 years (mean ± SD), participated in this study. Participants in the physical activity group (n = 11) were asked to increase their activities above their usual lifestyle levels for 12 weeks. Participants in the control group (n = 15) maintained their usual lifestyle for 12 weeks. All participants rested and consumed a standardized breakfast after a 24-h period of physical activity avoidance at baseline, 4 weeks, and 12 weeks. Blood samples were collected in the fasted state (0 h) and at 2, 4, and 6 h after breakfast. RESULTS: The average increased time spent in self-selected activities per day was 1.1 ± 19.3 min over the 12 weeks compared with the baseline in the physical activity group. There was no difference in the postprandial time-averaged triglyceride area under the curve at baseline (1.59 ± 0.81 vs. 1.39 ± 0.67 mmol/L, p = 0.515) or over the 12-week intervention (1.78 ± 1.00 vs. 1.31 ± 0.67 mmol/L, p = 0.212) between the physical activity and control groups. CONCLUSION: Postprandial triglyceride concentrations were not reduced after performing self-selected activities under free-living conditions in older women when these responses were determined 24 h after the last physical activity bout. (Trial registration ID: UMIN000037420).

Effects of a single bout of walking on postprandial triglycerides in men of Chinese, European and Japanese descent: a multisite randomised crossover trial.

INTRODUCTION: Elevated non-fasting triglyceride (TG) concentrations are a risk factor for cardiovascular diseases but can be reduced after acute exercise. Ethnic-based differences in the magnitude of postprandial lipaemia and the extent that acute exercise reduces postprandial TG are poorly characterised across some ethnicities including those of East Asian origin. This paper describes the protocol of a multisite randomised crossover study comparing the effect of acute walking on postprandial TG in two groups of East Asian men with European men. METHODS AND ANALYSIS: Twenty Japanese, 20 Singaporean Chinese and 20 white British healthy men (21-39 years) recruited from Japan, Singapore and the UK, respectively, will complete two, 2-day trials. Fasted and postprandial venous blood samples and arterial blood pressure measurements will be taken over 6 hours the day after either: (1) 60-min treadmill walking; or (2) a rest day of normal living. The primary outcome is the difference in postprandial TG among ethnic groups after rest and walking. Secondary outcomes include cholesterol, glucose, insulin, ketone bodies, preheparin lipoprotein lipase, C-reactive protein and systolic/diastolic blood pressure. ETHICS AND DISSEMINATION: The study was approved by the Ethics Review Committee on Research with Human Subjects of Waseda University and the Nanyang Technological University Institutional Review Board. Relevant approval will be obtained from the UK site. Research findings will be disseminated through peer-reviewed journal publication and health conferences. TRIAL REGISTRATION NUMBER: UMIN000038625.

Correction to: Energy replacement diminishes the postprandial triglyceride­lowering effect from accumulated walking in older women.

The original version of this article unfortunately contained a mistake. The error of NEFA AUC values in first (mean and 95% CI) and the main text (effect size and 95% CI).

Energy replacement diminishes the postprandial triglyceride-lowering effect from accumulated walking in older women.

PURPOSE: Dietary replacement of an acute exercise-induced energy deficit offsets the postprandial triglyceride (TG)-lowering effect of exercise in young boys and middle-aged men. It is unclear whether these findings are observed when exercise is accumulated in older adults. This study examined the effect of accumulating short bouts of exercise, with and without dietary replacement of an exercise-induced energy deficit, on postprandial TG in older women. METHODS: Seventeen older women (≥ 65 years) underwent three, 8-h trials: (1) control, (2) accumulated walking and (3) accumulated walking with energy replacement. During the control trial, participants rested for 8 h. The accumulated walking trials comprised twenty 1.5 min brisk walking bouts performed at a pre-determined self-selected pace separated by 15 min seated rest. In each trial, participants consumed a standardised breakfast and lunch. The breakfast in the accumulated walking with energy replacement trial included replacement of the energy deficit (0.62 MJ, 149 kcal) induced by exercise. Venous blood samples were collected fasted and at 2, 4, 6 and 8 h after breakfast. RESULTS: Time-averaged postprandial serum TG concentrations over 8 h were lower after accumulated walking than control and accumulated walking with energy replacement (mean ± SD: 1.46 ± 0.93 vs 1.71 ± 1.01 vs 1.60 ± 0.98 mmol/L, respectively: main effect of trial p = 0.017). There was little difference between control and accumulated walking with energy replacement. CONCLUSIONS: Replacing the energy expenditure induced by accumulating 30 min of brisk walking in short (1.5 min) bouts diminishes the postprandial TG-lowering effect in older women.