Gastric Emptying during Walking and Running: Effects of Varied Exercise Intensity

摘要

Gastric emptying is increased during running (50-70% maximal aerobic uptake, VO2 max) as compared to rest. Whether this increase varies as a function of mode (i.e., walking vs running) and intensity of treadmill exercise is unknown. To examine the gastric emptying characteristics of water during treadmill exercise performed over a wide range of intensities relative to resting conditions, 10 males ingested 40 ml of water prior to each of six 15-min exercise bouts or 15 min of seated rest. Three bouts of walking exercise (1.57 m/sec) were performed at increasing grades eliciting approx. 28, 41 or 56% of VO2 max. On a separate day, three bouts of running (2.60 m/sec) exercise were performed at grades eliciting approx. 57, 65 or 75% VO2 max. Gastric emptying was increased during treadmill exercise at all intensities excluding 75% VO2 max as compared to rest. Gastric emptying was similar for all intensities during walking and at 57 and 65% VO2 max during running. However, running at 74% VO2 max decreased the volume of original drink emptied as compared to all lower exercise intensities. Stomach secretions were markedly less during running as compared to walking and rest. These data demonstrate that gastric emptying is similarly increased during both moderate intensity (approx. 28-65% V02 max) walking or running exercise as compared to resting conditions.