Association of morning and evening physical exercise with sleep quality and insomnia: differences between chronotypes

Abstract

Objective: to investigate the association of morning and evening physical exercise with sleep quality (duration, latency, awakenings, and self-perceived sleep quality) and insomnia, depending on the chronotype. Methods: Participants (n=2,050; 18-65y) were part of a population-based research, with virtual data collection. Multiple logistic regression models were conducted to analyze the association of physical exercise (yes/no; frequency; morning/evening) with sleep variables (outcome), among all participants and according to chronotype. Linear regression analysis assessed differences in sleep duration, latency, and nocturnal awakenings (outcomes) associated with physical exercise variables. Multiple analyzes were adjusted for age, sex, diet quality, BMI, smoking, and evening alcohol consumption. Results: Participants who performed physical exercise had better sleep parameters and its practice in the morning was associated with shorter sleep latency among early (OR=-0.49; 95%CI=0.25;0.94; p<0.05) and late chronotypes (β=-15.10; 95%CI=-28.39;-1.81; p<0.05). There was no effect of exercising in the evening among intermediate and late chronotypes, however, among early types, it was associated with a higher frequency of awakenings (OR=1.78; 95%CI=1.06;2.96; p<0.05) and insomnia (OR=1.91; 95%CI=1.04;3.53; p<0.05). Conclusions: Such findings suggest the need to consider chronotypes, along with existing recommendations for sleep hygiene and circadian hygiene, in clinical-epidemiological physical activity strategies focused on promoting sleep quality and circadian health.