Physiological and Perceptual Responses to Incremental Exercise After Acute Sleep Deprivation

Abstract

Chronic sleep disruption has known consequences for health, but our understanding of the effects of acute total sleep deprivation on exercise capacity is limited. Previous studies, conducted mostly in highly fit males, report elevated ratings of perceived exertion after acute sleep deprivation, despite either unaltered or impaired exercise performance, but the physiologic mechanisms governing these elevated perceptual responses during exercise after acute sleep deprivation are yet to be elucidated. Moreover, it is unknown if specific exercise-related symptoms (dyspnea, leg discomfort) are elevated after sleep deprivation. The impact of one night of total sleep deprivation (DEP; 30-34h awake) on physiologic and specific perceptual responses to incremental 20 Watts x 2 min exercise on a cycle ergometer was assessed in 20 (10 male:10 female) healthy individuals after a night of DEP and a night of regular sleep (REG; visits randomized). Standard cardiopulmonary exercise measurements were recorded, along with diaphragmatic electromyography (inspiratory neural drive; IND), respiratory mechanics, dyspnea, and leg discomfort via modified Borg CR10 scale. DEP did not impact most physiological parameters throughout exercise or at peak, with minimal reduction in maximal work rate (REG: 179 ± 49 vs DEP: 173 ± 46 W; p=0.055) and consistently reduced end-tidal carbon dioxide production (REG: 41.0 ± 7.0 vs DEP: 39.7 ± 5.3 mmHg; p=0.02). DEP did not alter IND or respiratory mechanics. While DEP did not alter the intensity (Borg) of perceptual responses, trends towards sex-specific alterations in the quality of dyspnea experienced during DEP (increased selection of greater “work/effort” in females) were evident but did not reach significance. (p=0.057). Participant baseline characteristics largely did not explain susceptibility to increased symptom perception after DEP; however, baseline Emotional Intelligence scores were negatively correlated with the difference in peak dyspnea intensity between REG and DEP (r=- 0.558; p = 0.013). These findings suggest that one night of wakefulness is insufficient to meaningfully alter exercise capacity or perceptual responses in young healthy adults regardless of sex. However, participant-specific characteristics may influence the nature of individual susceptibility to the perceptual effects of sleep deprivation.