FEMALES DO NOT BENEFIT FROM INGESTING SOLID FIBER AND CHO FOOD
Kirwan, J. P., O'Gorman, D., Campbell, D., Yarasheski, K. E., & Evans, W. J. (1997). Effects of a pre-exercise breakfast cereal on exercise performance and glucose production. Medicine and Science in Sports and Exercise, 29(5), Supplement abstract 726.
Whether a breakfast cereal with high soluble fiber content and moderate glycemic index could facilitate a glucose sparing effect on muscle and liver and enhance exercise performance was investigated.
Active females (N = 6) ate 75 gm of available carbohydrate in the form of regular whole grain rolled oats mixed with 300 ml of water, or water alone 45 min prior to exercise. Semi-recumbent cycling was performed (60% VO2max) to exhaustion.
Performance and physiological factors were similar between both trials. The breakfast cereal did not yield any advantage. This finding may be an artifact of gender since females do not respond to CHO supplementation to the same magnitude or in a manner similar to males.
Implication. Females do not benefit from ingesting solid CHO-fiber foods (cereals) 45 min prior to performing endurance exercise.