March 11, 2011
Exposure to Room Light before Bedtime Suppresses Melatonin Onset and Shortens Melatonin Duration

This is not an exercise or nutrition study but I felt the need to post it because sleep is a very important aspect of those participating in sports or exercise routines.  Lack of sleep can lead to delayed muscle recovery, which in turn will lead to a decrease in performance.  Therefore, researchers from the U.K. tested the hypothesis that exposure to room light in thelate evening suppresses the onset of melatonin synthesis andshortens the duration of melatonin production.  Individuals were exposed to room light or dim light in the 8h preceding bedtime.  Compared with dim light, exposure to room light before bedtimesuppressed melatonin, resulting in a later melatonin onset in99.0% of individuals and shortening melatonin duration by about 90 min. Also, exposure to room light during the usual hoursof sleep suppressed melatonin by greater than 50% in most (85%) trials.

Conclusions: These findings indicate that room light exerts a profound suppressiveeffect on melatonin levels and shortens the body’s internalrepresentation of night duration. Hence, chronically exposing oneself to electrical lighting in the late evening disrupts melatonin signaling and could therefore potentially impact sleep, thermoregulation, blood pressure, and glucose homeostasis.

The Journal of Clinical Endocrinology & Metabolism, doi:10.1210/jc.2010-2098
J Clin Endocrinol Metab, Vol. 96 (3): 463-472

  1. tharidra reblogged this from exercisescience and added:
    Turn off those lights!
  2. foods-that-boost-metabolism reblogged this from exercisescience
  3. aerobic-exercise reblogged this from exercisescience
  4. ninabina89 reblogged this from exercisescience
  5. chewingovertheissues reblogged this from ajebsary and added:
    I wonder if they looked at the effect of different colors of light, or if they were just looking at bright-vs-dim. Many...
  6. doctor-tiger-fucker reblogged this from exercisescience
  7. firiona reblogged this from exercisescience
  8. kiss-me-on-myneck reblogged this from exercisescience
  9. scarlamira reblogged this from ajebsary
  10. wornoutguitar reblogged this from exercisescience
  11. mauriciotagliari reblogged this from exercisescience
  12. abbakafka reblogged this from exercisescience and added:
    For Sophie. And me. -ak
  13. exercisescience posted this