Document Type : Review Article
Authors
1 Department of Sport Sciences, International Division, Shiraz University, Shiraz, Iran
2 Imam Ali Military University, Army of the Islamic Republic of Iran, Tehran, Iran
3 Department of Exercise Physiology, Faculty of Sport Sciences, Shiraz University, Shiraz, Iran
Abstract
Background: Sleep quality is a key determinant of physical recovery, cognitive performance, and overall health. High-intensity interval training (HIIT) has emerged as a time-efficient exercise strategy with potential benefits for sleep regulation; however, the physiological mechanisms underlying these effects remain incompletely understood.
Objective: This narrative review aimed to critically evaluate the current evidence regarding the role of HIIT in sleep quality regulation, with particular emphasis on inflammation, circadian rhythms, and the gut-brain axis.
Methods: Literature published between 2000 and 2026 was identified through searches of PubMed, Scopus, Web of Science, and Google Scholar. Peer-reviewed original studies, randomized controlled trials, observational studies, systematic reviews, meta-analyses, and mechanistic reviews relevant to HIIT, sleep quality, inflammation, circadian biology, autonomic regulation, and the gut-brain axis were synthesized narratively.
Results: The available evidence was interpreted according to direct evidence, indirect physiological associations, and emerging mechanistic hypotheses. Overall, current evidence suggests that HIIT may support sleep quality primarily through improvements in cardiometabolic health, autonomic recovery, inflammatory regulation, and circadian entrainment. Gut-brain axis mechanisms remain biologically plausible but are supported mainly by emerging evidence, and direct causal evidence linking HIIT-induced microbiome adaptations to improvements in sleep quality remains limited.
Conclusion: HIIT appears to be a promising non-pharmacological strategy for improving sleep quality. However, the strength of evidence differs across the proposed mechanisms, and further well-designed longitudinal mechanistic studies integrating objective sleep assessment, inflammatory biomarkers, autonomic monitoring, and microbiome profiling are needed to clarify causal pathways and optimize exercise prescriptions for sleep health.
Keywords
- Exercise Immunology
- Melatonin
- Cytokines
- Microbiota
- Chronobiology
- Neuroendocrine Adaptation
- Autonomic Regulation
- Short-Chain Fatty Acids
- Metabolic Health
Main Subjects
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