Total Sleep Duration
hours
Total sleep obtained, used as the sleep quantity input to the Recovery Score.
Typical optimal range 7 hr - 9 hr
Population median 6.6 hr
Key factors
- Work schedule and shift length
- Intentional sleep prioritization
- Napping behavior
What affects this metric
- Shift work and early alarms are the most common causes of short duration.
- Bedtime and alarm time set duration more than anything else.
- Late caffeine and screens shorten it by delaying onset.
- No amount of sleep quality compensates fully for too little of it.
References
Peer-reviewed sources supporting the key factors, contributing factors, and typical optimal range shown above.
- Hirshkowitz M, Whiton K, Albert SM, et al.. National Sleep Foundation's sleep time duration recommendations: methodology and results summary. Sleep Health. 2015;1(1):40–43. doi.org/10.1016/j.sleh.2014.12.010
- Van Dongen HPA, Maislin G, Mullington JM, Dinges DF. The cumulative cost of additional wakefulness: dose-response effects on neurobehavioral functions and sleep physiology from chronic sleep restriction and total sleep deprivation. Sleep. 2003;26(2):117–126. doi.org/10.1093/sleep/26.2.117
- Boivin DB, Boudreau P, Kosmadopoulos A. Disturbance of the circadian system in shift work and its health impact. Journal of Biological Rhythms. 2022;37(1):3–28. doi.org/10.1177/07487304211064218
This guide is general information, not medical advice. Talk to your clinician about your own results.