Cycles and timing
Through the night you move through light, deep and REM sleep in cycles of roughly 90 minutes. Deep sleep dominates early in the night, REM later. Waking at the end of a cycle often feels easier.
Why it matters for training
7–9 hrecommended for adults
90 minis the average length of one sleep cycle
2 hbefore bed: aim to finish heavy meals by then
Short sleep lowers motivation, raises perceived effort and makes recovery slower. Over time it nudges appetite up, which works against fat loss.
Habits that help
Do
- Keep the same wake time every day
- Dark, cool, quiet room
- Daylight soon after waking
- A short wind-down routine
Avoid
- Caffeine late in the afternoon
- Alcohol as a sleep aid
- Bright screens in bed
- Big catch-up lie-ins
Key takeaways
- Aim for 7–9 hours, at regular times
- Wake at the end of a cycle when you can
- Protect the last hour before bed
General information, not medical advice. If you have a health condition, are pregnant, or take medication, check with a professional first. See the medical disclaimer.
Sources
- Watson NF et al. Recommended amount of sleep for a healthy adult. AASM and SRS consensus. Sleep, 2015.
- Fullagar HHK et al. Sleep and athletic performance. Sports Med, 2015.