The Effect of Water Loading for Acute Weight Loss Following Fluid Restriction on Sleep Quality and Quantity in Combat Sports Athletes

Main Article Content

Ian C Dunican
Peter R Eastwood
Kevin Murray
John A Caldwell
Reid Reale


Weight-Cutting, Body Composition, Athlete Monitoring


Introduction: Combat sport athletes commonly engage in established and novel acute weight-loss strategies to achieve weight division targets. The effect of such practices on sleep is unknown.

Methods: Twenty-two combat sports athletes wore wrist actigraphy devices for nine nights during a training camp and completed questionnaires assessing daytime sleepiness, insomnia, sleep apnoea and chronotype. Athletes were assigned to a control (CG) or water loading group (WLG). Both followed a low residue diet for 96h, and restricted fluid for 24h before weigh-in. Prior to restriction, the CG consumed 40ml/kg and WLG consumed 100ml/kg fluid daily.

Results: Four athletes responded positively for the potential prevalence of sleep apnoea (2 CG/WLG), reporting subthreshold insomnia 8±4, athletes were assessed as having an “intermediate chronotype”. Sleep latency estimates in CG were longer on days 4/6 relative to 3 (p<0.05). There was a between-group difference for sleep latency on day 6, with CG taking 35 mins longer (95% CI 5-64mins, p=0.022) to fall asleep.

Conclusion: Acute weight loss by means of a low residue diet, both with and without water loading before the fluid restriction is a safe and effective means of manipulating body mass to in the context of sleep.

Abstract 83 | PDF Downloads 115


1. Reale R, Cox GR, Slater G, Burke LM. Regain in Body Mass After Weigh-In is Linked to Success in Real Life Judo Competition. International journal of sport nutrition and exercise metabolism. 2016.

2. Reale R, Slater G, Cox GR, Dunican IC, Burke LM. The Effect of Water Loading on Acute Weight Loss Following Fluid Restriction in Combat Sports Athletes. International journal of sport nutrition and exercise metabolism. 2018:1-9.

3. Reale R, Slater G, Burke LM. Acute Weight Loss Strategies for Combat Sports and Applications to Olympic Success. International Journal ofSports Physiology and Performance. 2016:1-30.

4. Fullagar HH, Skorski S, Duffield R, Hammes D, Coutts AJ, Meyer T. Sleep and athletic performance: the effects of sleep loss on exercise performance, and physiological and cognitive responses to exercise. Sports medicine (Auckland, NZ). 2015;45(2):161-186.

5. Erlacher D, Ehrlenspiel F, Adegbesan OA, El-Din HG. Sleep habits in German athletes before important competitions or games. Journal of sports sciences. 2011;29(8):859-866.

6. Juliff LE, Halson SL, Pfeiffer JJ. Understanding sleep disturbance in athletes prior to important competitions. Journal of science and medicine in sport / Sports Medicine Australia. 2015;18(1):13-18.

7. Bastien CH, Vallieres A, Morin CM. Validation of the Insomnia Severity Index as an outcome measure for insomnia research. Sleep medicine. 2001;2(4):297-307.

8. Chervin RD, Aldrich MS, Pickett R, Guilleminault C. Comparison of the results of the Epworth Sleepiness Scale and the Multiple Sleep Latency Test. Journal of Psychosomatic Research. 1997;42(2):145-155. 9. Enciso R, Clark GT. Comparing the Berlin and the ARES questionnaire to identify patients with obstructive sleep apnea in a dental setting. Sleep & breathing = Schlaf & Atmung. 2011;15(1):83-89.

10. Horne JA, Östberg O. A self-assessment questionnaire to determine morningness-eveningness in human circadian rhythms. International Journal of Chronobiology. 1976; 4:97-110.

11. Dunican IC, Murray K, Slater JA, et al. Laboratory and home comparison of wrist-activity monitors and polysomnography in middle-aged adults. Sleep and Biological Rhythms. 2018;16(1):85-97.

12. Russell CA CJ, Arand D, Myers LJ, Wubbels P, Downs H. Controlling fatigue risk with the Fatigue Science ReadiBand actigraph and associated sleep/wake classification algorithms: use case and validation. Fatigue Science: Fatigue Science;2006.

13. Dunican IC, Martin DT, Halson SL, et al. The Effects of the Removal of Electronic Devices for 48 hours on Sleep in Elite Judo Athletes. Journal of strength and conditioning research / National Strength & Conditioning Association. 2017.

14. Dunican IC, Higgins CC, Jones MJ, et al. Caffeine use in a Super Rugby game and its relationship to post-game sleep. European journal of sport science. 2018:1-11.

15. Readiband FDA Approval FS. FDA Approval for Readiband-K111514 -SBV2. In. Federal Drug Administration Federal Drug Administration 2011:6.

16. Robert Adams, S.A., Anne Taylor, Doug McEvoy, and Nick Antic, Report to the Sleep Health Foundation 2016 Sleep Health Survey of Australian Adults. 2016, The University of Adelaide: The Adelaide Institute for Sleep Health: Sleep Health Foundation.

17. St-Onge MP, Roberts A, Shechter A, Choudhury AR. Fiber and Saturated Fat Are Associated with Sleep Arousals and Slow Wave Sleep. Journal of clinical sleep medicine: JCSM: official publication of the American Academy of Sleep Medicine. 2016;12(1):19-24.

18. Ancoli-Israel, S., D.L. Bliwise, and J.P. Nørgaard, The effect of nocturia on sleep. Sleep medicine reviews, 2011. 15(2): p. 91-97.

19. Aristotelous, P., et al., Effects of controlled dehydration on sleep quality and quantity: A polysomnographic study in healthy young adults. J Sleep Res, 2018.