Why tired athletes can't sleep well
High cortisol levels as a risk factor for athletes poor sleep quality in training centers
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
Surprising Findings
Neither age nor gender independently affected sleep quality—only cortisol levels did.
We assume younger athletes or women are more vulnerable to sleep issues, but this study shows stress hormone levels trump demographics entirely.
Practical Takeaways
Coaches and athletes should consider a morning cortisol blood test if sleep quality drops—especially if PSQI scores exceed 5.
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
Surprising Findings
Neither age nor gender independently affected sleep quality—only cortisol levels did.
We assume younger athletes or women are more vulnerable to sleep issues, but this study shows stress hormone levels trump demographics entirely.
Practical Takeaways
Coaches and athletes should consider a morning cortisol blood test if sleep quality drops—especially if PSQI scores exceed 5.
Publication
Journal
International Journal of Research in Medical Sciences
Year
2025
Authors
Ni Nyoman Mestri Agustini, A. A. B. N. Nuartha, A. Laksmidewi
Related Content
Claims (6)
In athletes with high levels of the stress hormone cortisol, there is a measurable link to worse sleep quality, as determined by a standard sleep questionnaire.
In elite athletes training for national competitions, a blood cortisol level of 208.05 nmol/L or higher is associated with a 75% chance of correctly identifying poor sleep quality and a 71.9% chance of correctly identifying good sleep quality, suggesting it could be used as a biological indicator to detect sleep disruption.
Athletes who sleep poorly are more likely to have elevated cortisol levels than those who sleep well, even when accounting for differences in sport, gender, and age. This suggests cortisol levels may be a stronger indicator of stress-related physiology than these demographic factors.
Among athletes with intense training schedules, differences in sleep quality are not reliably linked to whether someone is male or female, or to their age, once cortisol levels are taken into account.
In athletes undergoing intense training, differences in sleep quality are not clearly linked to whether they compete in athletics or other sports once you account for their cortisol levels, suggesting that overall training stress may matter more than the specific sport.