A replicate crossover trial on the interindividual variability of sleep indices in response to acute exercise undertaken by healthy men

Yang, Yuting, Thackray, Alice E ORCID: https://orcid.org/0000-0002-7800-3207, Shen, Tonghui, Alotaibi, Tareq F, Alanazi, Turki M, Clifford, Tom, Hartescu, Iuliana ORCID: https://orcid.org/0000-0001-5125-9096, King, James A, Roberts, Matthew J ORCID: https://orcid.org/0000-0003-2952-103X, Willis, Scott A ORCID: https://orcid.org/0000-0001-8624-1427, Lolli, Lorenzo, Atkinson, Greg and Stensel, David J (2024) A replicate crossover trial on the interindividual variability of sleep indices in response to acute exercise undertaken by healthy men. SLEEP. zsae250. ISSN 1550-9109

Preview

Published Version Available under License Creative Commons Attribution Non-commercial. Download (2MB) | Preview

Abstract

Study Objectives: Using the necessary replicate-crossover design, we investigated whether there is interindividual variability in home-assessed sleep in response to acute exercise. Methods: Eighteen healthy men (mean [SD]: 26[6] years) completed two identical control (8 hour laboratory rest, 08:45–16:45) and two identical exercise (7 hour laboratory rest; 1 hour laboratory treadmill run [62(7)% peak oxygen uptake], 15:15–16:15) trials in randomized sequences. Wrist-worn actigraphy (MotionWatch 8) measured home-based sleep (total sleep time, actual wake time, sleep latency, and sleep efficiency) two nights before (nights 1 and 2) and three nights after (nights 3–5) the exercise/control day. Pearson’s correlation coefficients quantified the consistency of individual differences between the replicates of control-adjusted exercise responses to explore: (1) immediate (night 3 minus night 2); (2) delayed (night 5 minus night 2); and (3) overall (average post-intervention minus average pre-intervention) exercise-related effects. Within-participant linear mixed models and a random-effects between-participant meta-analysis estimated participant-by-trial response heterogeneity. Results: For all comparisons and sleep outcomes, the between-replicate correlations were nonsignificant, ranging from trivial to moderate (r range = −0.44 to 0.41, p ≥ .065). Participant-by-trial interactions were trivial. Individual differences SDs were small, prone to uncertainty around the estimates indicated by wide 95% confidence intervals, and did not provide support for true individual response heterogeneity. Meta-analyses of the between-participant, replicate-averaged condition effect revealed that, again, heterogeneity (τ) was negligible for most sleep outcomes. Conclusions: Control-adjusted sleep in response to acute exercise was inconsistent when measured on repeated occasions. Interindividual differences in sleep in response to exercise were small compared with the natural (trial-to-trial) within-subject variability in sleep outcomes. Clinical trials information: https://clinicaltrials.gov/study/NCT05022498. Registration number: NCT05022498.