Physiological and perceptual responses during walking at set and preferred pace in normal and overweight adults.

Abstract

This study aimed to investigate the influence of body weight, exercise modality, and pace on physiological and perceptual responses to determine the relation between perceptual and physiological responses. Aerobically untrained, normal weight, and overweight males and females participated. Participants were randomly assigned to one exercise condition for a 1-mile walk. Prescribed pace resulted in a greater physiological stress than self-selected pace (all p < 0.001) through blood lactate (1.3 ± 0.4 vs 1.7 ± 0.5 mmol), systolic blood pressure (128.9 ± 10.3 vs 139.2 ± 13.2 mmHg), heart rate recovery (2.1 ± 1.7 vs 4.5 ± 2.6 min), oxygen consumption (15.1 ± 2.6 vs 18.1 ± 3.6 ml/kg/min), heart rate (111.7 ± 16.6 vs 134.4 ± 8.3 bpm), and energy expenditure (5.5 ± 1.4 vs 6.8 ± 1.7 kcal/min). Overweight individuals exhibited higher values than normal weight for heart rate (113 ± 8.8 vs 125.5 ± 13.2 bpm, p < 0.001), percentage of max heart rate (60.7 vs 69.0%, p < 0.001), percent of VO₂peak (42.2 vs 55.6%, p < 0.001), and total energy expenditure (100.9 ± 27.4 vs 114.1 ± 33.5 kcal, p = 0.022). Greater perceived effort was seen on a treadmill (6.3 ± 0.5 vs 12.5 ± 2.0 RPE, p < 0.001) and at prescribed pace (6.5 ± 1.1 vs 8.9 ± 1.9 RPE, p < 0.001). A novel finding of this study was the increased physiological stress and perception of effort on a treadmill and at a prescribed pace, while total energy expenditure showed no significant differences. This could indicate an unfavorable perception and less affective response to the treadmill modality. These results indicate exercise at self-selected pace in preferred environments promotes enjoyable experiences with similar health benefits as those during prescribed higher intensity exercise.