Abstract
Background/Objectives: Characterizing compensatory and adaptive responses to exercise assists in understanding changes in energy balance and health outcomes with exercise interventions. This study investigated the effects of a short-term exercise intervention (combining high intensity interval (HII) and continuous exercise) on (1) gastric emptying, appetite and energy intake; and (2) other adaptive responses including cardiorespiratory fitness, in inactive men with overweight/obesity.Methods: Fifteen men (BMI: 29.7 ± 3.3 kg/m−2) completed a 4-wk supervised exercise intervention, consisting of 5 exercise sessions per week alternating between HII (30 s at 100% VO2max followed by 30 s recovery) and continuous (at 50% VO2max) training on a cycle ergometer, progressing from 30 to 45 min session duration. Gastric emptying (13C-octanoic acid breath test), appetite (visual analog scale), energy intake (ad libitum lunch meal), body composition (air displacement plethysmography), non-exercise activity (accelerometery) VO2max, blood pressure, and fasting concentrations of glucose, insulin, and ghrelin were measured before and after (≥48 h) the intervention.Results: Gastric emptying, glucose, insulin and ghrelin were unchanged, but energy intake at the ad libitum lunch test meal significantly increased at post-intervention (+171 ± 116 kcal, p < 0.01). Body weight (−0.9 ± 1.1 kg), waist circumference (−2.3 ± 3.5 cm) and percent body fat (−0.9 ± 1.1%) were modestly reduced (P < 0.05). VO2max increased (+4.4 ± 2.1 ml.kg.min−1) by 13% and systolic (−6.2 ± 8.4 mmHg) and diastolic (−5.8 ± 2.2 mmHg) blood pressure were significantly reduced (P ≤ 0.01 for all).Conclusions: Four weeks of exercise training did not alter gastric emptying, indicating gastric emptying may only adapt to a higher volume/longer duration of exercise or changes in other characteristics associated with regular exercise. The combination of HII and continuous exercise training had beneficial effects on body composition, cardiorespiratory fitness, and blood pressure and warrants further investigation in larger randomized controlled trials.
Highlights
Exercise has many health benefits, including weight maintenance, and should be an effective weight loss strategy by increasing energy expenditure
We have previously hypothesized that faster gastric emptying with chronic exercise could be one mechanism contributing to an overall increase in meal frequency and energy intake by reducing gastric distension and fullness, but improved ability to match daily energy intake to expenditure in active individuals through enhanced intestinal satiety signaling [15]
Results are presented for 15 men (BMI: 29.7 ± 3.3, Age: 31.1 ± 8.4 yr) who completed all parts of the study
Summary
Exercise has many health benefits, including weight maintenance, and should be an effective weight loss strategy by increasing energy expenditure. We have previously hypothesized that faster gastric emptying with chronic exercise could be one mechanism contributing to an overall increase in meal frequency and energy intake by reducing gastric distension and fullness, but improved ability to match daily energy intake to expenditure in active individuals through enhanced intestinal satiety signaling [15]. Such relationships have yet to be investigated. While cross-sectional studies can provide important information, they do not allow for a causal relationship between changes in gastric emptying with repeated exercise training to be determined
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
