Toward a Standardized Framework for Assessing Athletes’ Sleep: Determinants, Tools, and Practical Applications

This review aims to provide a critical appraisal of the principal methods used for sleep assessment in athletic populations. Polysomnography remains the reference method for diagnosis and sleep staging, but its practical application is constrained in athletes. For season-long monitoring, actigraphy coupled with a standardized sleep diary serves as the cornerstone for assessing sleep duration and timing, with explicit reporting of means and intra-individual variability (sleep onset, mid-sleep, total sleep time). Consumer wearables broaden accessibility yet show inconsistent accuracy for sleep staging, whereas nearables are well suited for unobtrusive long-term monitoring and screening. Emerging technologies such as wearable EEG and multi-sensor patches demonstrate rapid progress toward enabling multi-night staging and the assessment of selected micro-indices in free-living settings. Method selection should be guided by macrostructure (initiation, duration, continuity, stages) and microstructure (slow waves, spindles, CAP, REM phasic activity). This review provides an evidence-informed decision algorithm to guide tool selection in both research and applied sports settings. Its application is illustrated using two real-world case scenarios.