1. Physical Activity & Sleep EPHE 348

2. Sleep – What is it good for?  Insomnia is a major public health issue (20-40%)  Results in mood and psychiatric issues, reduced efficiency, and accidents  Drugs have their own health risks…(tolerance) need behavioural sleep management strategies

3. Sleep Characteristics  Onset  Wake after onset  Stages of Sleep (NREM & REM)  Total Time

4. Sleep  Stage 1 – NREM 5% of sleep 5% of sleep Transition from wakefulness Transition from wakefulness  Stage 2 NREM 50% of sleep 50% of sleep Intermediate sleep Intermediate sleep  Stage 3&4 NREM 20% of sleep 20% of sleep Slow wave typical in first third of sleep Slow wave typical in first third of sleep  REM 25% of sleep 25% of sleep 90 min cycles and mostly in last third of sleep 90 min cycles and mostly in last third of sleep

5. PA & Sleep  Ranked a salient factor in surveys  Almost accepted as a universal truth  Parents & Kids  But…..is it really important?

6. Youngstedt et al. 1997, 2000  Meta-analyses of 38 laboratory studies Sleep onset (ES = -.05) Sleep onset (ES = -.05) Wake after sleep (ES =.07) Wake after sleep (ES =.07) NONREM stage 2 (ES =.18) NONREM stage 2 (ES =.18) NONREM stage 3-4 (ES =.19) NONREM stage 3-4 (ES =.19) REM sleep (ES = -.49; 7 min) REM sleep (ES = -.49; 7 min) Total sleep time (ES =.42; 10 min) Total sleep time (ES =.42; 10 min)

7. Summary of Meta-analysis  Clinical significance is dubious  Note that most participants were good sleepers (ceiling effect)  Proximity to bedtime PA and wakefulness was not supported (myth)

8. Youngstedt & Kline, 2006  Sleep lab studies perhaps limited by ecological validity and non-representative samples….  Review of survey studies Exercise ranks as most important to sleep practices Exercise ranks as most important to sleep practices Bedtime PA and sleep also not supported by surveys Bedtime PA and sleep also not supported by surveys Consistent association between sleep quality and exercise (though it lags behind stress & Depression) Consistent association between sleep quality and exercise (though it lags behind stress & Depression)