Partington, S., Stupka, N., Rennie, C., Ridell, M., Armstrong, D., & Tarnopolsky, M. A. (2000). Exogenous carbohydrate supplementation suppresses endogenous carbohydrate and protein oxidation in males and females. Medicine and Science in Sports and Exercise, 32(5), Supplement abstract 1063.

"We have previously demonstrated that females oxidized proportionately more liquid during endurance exercise and did not increase muscle glycogen in response to an increased dietary carbohydrate intake as compared to males" (p. S225). This study assessed whether there were gender differences in exogenous carbohydrate oxidation during exercise. Healthy males (N = 7) and females (N = 7) served as Ss. Two trials (90 minutes at 60% VO2max) were performed. One was with CHO supplementation and the other with a placebo.

CHO supplementation resulted in a significant reduction in both endogenous CHO and protein oxidation. Females displayed a higher rate of exogenous CHO oxidation late in the supplementation trial than did males, although total exogenous oxidation was similar between genders. Respiratory exchange ratio was lower for females at 30 minutes than for males.

Implication. Both genders oxidize similar amounts of exogenous CHO in endurance performance, but females do so with a different pattern of use than males.

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