Effectiveness of Glycerol as a Rehydrating Agent
Human Performance and Recreation
On two occasions, 8 male subjects completed a dehydration protocol, immediately followed by a 180-min rehydration protocol, then a subsequent exercise bout. During each dehydration session, subjects lost 3.1 +/- 0.4% body weight (BW)following discontinuous exercise in the heat (40 degreesC, 33% rh). During the first 30 min of rehydration, subjects ingested either 1.0-g glycerol . kg body weight(-1) + 30% of the total rehydration water volume (GLY), or 30% of the total rehydration water volume without glycerol (CON). The five remaining ingestions (every 30 min) were equal to 14% of the remaining fluid volume and were identical in nature. Fluid volume ingested equaled fluid volume lost during dehydration. Following the 180 min rehydration period, subjects cycled (similar to 50% (V) over dot (2peak)) in the heat (40 degreesC, 33% rh) until volitional exhaustion. Three observations were made: (a) Following glycerol-induced rehydration, time to volitional exhaustion was greater during the subsequent exercise bout in the heat (CON: 38.0 +/- 2.0, GLY 42.8 +/- 1.0 min, p < .05); (b) glycerol-induced rehydration significantly increased plasma volume restoration within 60 min and at the end of the 180-min rehydration period; and (c) total urine volume was lower and percent rehydration was greater following GLY, but neither was significantly different.
International Journal of Sport Nutrition and Exercise Metabolism
Scheett, T. P.,
Webster, M. J.,
(2001). Effectiveness of Glycerol as a Rehydrating Agent. International Journal of Sport Nutrition and Exercise Metabolism, 11(1), 63-71.
Available at: http://aquila.usm.edu/fac_pubs/3943