Abstract
Purpose
The aim of the study was to examine the effects of a post-prandial 20 min nap on a short-term physical exercise and subsequent sleep in athletes keeping their usual sleep schedules and in 5-h phase-advance condition.
Methods
Sixteen healthy young male athletes (age 22.2 ± 1.7 years, non-habitual nappers) participated in the study. After a baseline 8-h time in bed in normal and 5-h advanced sleep schedules, a standardized morning and lunch in a laboratory environment, subjects underwent either a nap (20 min of sleep elapsed from 3 epochs of stage 1 or 1 epoch of stage 2), or a rest without sleep by lying in a bed, between 13:00 and 14:00 hours in non-shifted condition or 08:00 and 09:00 hours in shifted condition, after which anaerobic exercises were performed twice 2 h apart. Core body temperature was recorded throughout the study period.
Results
The nap extended sleep onset latency from 6.72 ± 3.83 to 11.84 ± 13.44 min, after shifted condition but did not modify sleep architecture of the post-trial night among athletes, whether shifted or not. Moreover, napping did not improve physical performance but it delayed acrophase and batyphase of core body temperature rhythm parameters.
Conclusion
Napping showed no reliable benefit on short-term performances of athletes exercising at local time or after a simulated jet lag.
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Abbreviations
- AASM:
-
American Academy of Sleep Medicine
- CBT:
-
Core body temperature
- EEG:
-
Electroencephalogram
- P mean :
-
Mean power
- P peak :
-
Peak power
- % N1:
-
Percentage in sleep stage 1
- % N2:
-
Percentage in sleep stage 2
- % N3:
-
Percentage in sleep stage 3
- % REM:
-
Percentage in rapid eye movement
- PSG:
-
Polysomnography
- PTN1:
-
Post-tests night 1
- PTN2:
-
Post-tests night 2
- PTPAN1:
-
Post-tests night with phase advance 1
- PTPAN2:
-
Post-tests night with phase advance 2
- SE:
-
Sleep efficiency
- SOL:
-
Sleep onset latency
- TST:
-
Total sleep time
- TTN1:
-
Total time in stage 1
- TTN2:
-
Total time in stage 2
- TTN3:
-
Total time in stage 3
- TTREM:
-
Total time in stage REM
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Acknowledgments
The authors are grateful to the athletes who participated in this study. We also thank Gaëlle Brunotte for editorial assistance.
Conflict of interest
The authors declare that they have no conflict of interest.
Ethical standards
The experiments comply with the current laws of the country in which they were performed.
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Communicated by Michael Lindinger.
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Petit, E., Mougin, F., Bourdin, H. et al. A 20-min nap in athletes changes subsequent sleep architecture but does not alter physical performances after normal sleep or 5-h phase-advance conditions. Eur J Appl Physiol 114, 305–315 (2014). https://doi.org/10.1007/s00421-013-2776-7
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DOI: https://doi.org/10.1007/s00421-013-2776-7