The central role of fatigue and sleep in health behaviors during the COVID-19 pandemic

Abstract

To explore the associations between perceived fatigue and various health behaviors in a Brazilian adult sample using network analysis during the COVID-19 pandemic. Data were collected via an online questionnaire between July 2020 and February 2021, including sociodemographic information, sleep quality, and validated instruments assessing physical activity, alcohol use, and stress. Perceived fatigue was assessed using two questions: (1) “Did you feel that everything you did was an effort?” and (2) “Were you unable to keep going?”. Responses were recorded on a 4-point Likert scale. The responses were summed to generate a continuous perceived fatigue score. Additionally, participants reporting both symptoms on three or more days were classified as “fatigued”. Network analysis was performed to examine the strength and direction of correlations and to evaluate node importance using centrality strength and expected influence metrics. Among 401 participants, 54% were classified as fatigued. Those experiencing fatigue were younger, reported higher stress levels, and had a greater prevalence of worsened sleep. Network analysis revealed that fatigue exhibited the highest strength centrality (1.37), sleep showed moderate strength (1.13), and physical activity demonstrated the highest positive expected influence (0.34). Sleep and perceived fatigue are central nodes shaping other health variables, suggesting that improving sleep quality and reducing fatigue, especially through physical activity, may represent promising targets for intervention.