AUTHOR=Romdhani Mohamed , Fullagar Hugh H. K. , Vitale Jacopo A. , Nédélec Mathieu , Rae Dale E. , Ammar Achraf , Chtourou Hamdi , Al Horani Ramzi A. , Ben Saad Helmi , Bragazzi Nicola Luigi , Dönmez Gürhan , Dergaa Ismail , Driss Tarak , Farooq Abdulaziz , Hammouda Omar , Harroum Nesrine , Hassanmirzaei Bahar , Khalladi Karim , Khemila Syrine , Mataruna-Dos-Santos Leonardo Jose , Moussa-Chamari Imen , Mujika Iñigo , Muñoz Helú Hussein , Norouzi Fashkhami Amin , Paineiras-Domingos Laisa Liane , Khaneghah Mehrshad Rahbari , Saita Yoshitomo , Souissi Nizar , Trabelsi Khaled , Washif Jad Adrian , Weber Johanna , Zmijewski Piotr , Taylor Lee , Garbarino Sergio , Chamari Karim
TITLE=Lockdown Duration and Training Intensity Affect Sleep Behavior in an International Sample of 1,454 Elite Athletes
JOURNAL=Frontiers in Physiology
VOLUME=13
YEAR=2022
URL=https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2022.904778
DOI=10.3389/fphys.2022.904778
ISSN=1664-042X
ABSTRACT=Objective: To investigate the effect of 1) lockdown duration and 2) training intensity on sleep quality and insomnia symptoms in elite athletes.
Methods: 1,454 elite athletes (24.1 ± 6.7 years; 42% female; 41% individual sports) from 40 countries answered a retrospective, cross-sectional, web-based questionnaire relating to their behavioral habits pre- and during- COVID-19 lockdown, including: 1) Pittsburgh sleep quality index (PSQI); 2) Insomnia severity index (ISI); bespoke questions about 3) napping; and 4) training behaviors. The association between dependent (PSQI and ISI) and independent variables (sleep, napping and training behaviors) was determined with multiple regression and is reported as semi-partial correlation coefficient squared (in percentage).
Results: 15% of the sample spent < 1 month, 27% spent 1–2 months and 58% spent > 2 months in lockdown. 29% self-reported maintaining the same training intensity during-lockdown whilst 71% reduced training intensity. PSQI (4.1 ± 2.4 to 5.8 ± 3.1; mean difference (MD): 1.7; 95% confidence interval of the difference (95% CI): 1.6–1.9) and ISI (5.1 ± 4.7 to 7.7 ± 6.4; MD: 2.6; 95% CI: 2.3–2.9) scores were higher during-compared to pre-lockdown, associated (all p < 0.001) with longer sleep onset latency (PSQI: 28%; ISI: 23%), later bedtime (PSQI: 13%; ISI: 14%) and later preferred time of day to train (PSQI: 9%; ISI: 5%) during-lockdown. Those who reduced training intensity during-lockdown showed higher PSQI (p < 0.001; MD: 1.25; 95% CI: 0.87–1.63) and ISI (p < 0.001; MD: 2.5; 95% CI: 1.72–3.27) scores compared to those who maintained training intensity. Although PSQI score was not affected by the lockdown duration, ISI score was higher in athletes who spent > 2 months confined compared to those who spent < 1 month (p < 0.001; MD: 1.28; 95% CI: 0.26–2.3).
Conclusion: Reducing training intensity during the COVID-19-induced lockdown was associated with lower sleep quality and higher insomnia severity in elite athletes. Lockdown duration had further disrupting effects on elite athletes’ sleep behavior. These findings could be of relevance in future lockdown or lockdown-like situations (e.g., prolonged illness, injury, and quarantine after international travel).