Using Glycerol For Pre-Exercise Fluid Loading

Glycerol is a natural compound that is similar in chemical structure to alcohol. It is present in the body in stored fat and in fluids and can also be purchased as a supplement to promote water retention. One effect of ingesting glycerol is an increase in blood plasma volume, which is potentially beneficial to athletes because it could slow the dehydration process during exercise. The journal Sports Medicine has published a new review on the use of glycerol for pre-exercise “hyperhydration” by researchers at the University of Queensland, Australia. In analyzing the results of numerous previous studies they conclude that glycerol is effective in hyperhydrating athletes before exercise, delaying dehydration during exercise, and improving thermoregulation during exercise and endurance performance. As for the proper protocol for glycerol use in pre-exercise fluid loading, the authors of this review report that “endurance athletes intending to hyperhydrate with glycerol should ingest glycerol 1.2 g/kg BW in 26 mL/kg BW of fluid over a period of 60 minutes, 30 minutes prior to exercise.”