Maintaining adequate hydration is critical to perform optimally and adapt to training. Exercising in hot and/or humid conditions puts athletes at risk of becoming dehydrated, which can impair performance even with small water losses. There may be additional benefits to hyper-hydrating, which may provide for a more anabolic environment for muscle cells. Beside water ingestion, there are few dietary strategies to augment water retention. Creatine
accumulates in muscle cells and thereby causes retention of water inside cells. Glycerol also has been shown to augment water retention primarily in the plasma. The combination of creatine
and glycerol therefore has the potential to hyper-hydrate more than each supplement alone. A recent study compared the individual and combined effects of creatine
and glycerol supplementation on total body water. Creatine
supplementation (22.8 g/day) and glycerol (1 g per kilogram body weight) each increased total body water, but the combination resulted in the greatest hyper-hydrating effect. The effects of this water-loading combination on long-term adaptations to training was not addressed, but would be interesting to examine in future studies.
Easton C, Turner S, Pitsiladis YP. Effects of Combined Creatine and Glycerol Supplementation on Physiological Responses During Exercise in the Heat: 1117: 9:00 AM - 9:15 AM. Med Sci Sports Exerc. 2006 May;38(5 Suppl):S125.