McInerney, P., Lo Giudice, S. L., Lessard, S. J., Coffey, V. G., Southgate, R. J., Burke, L. M., & Hawley, J. A. (2004). Failure of repeated carbohydrate loading to supercompensate muscle glycogen stores. Medicine and Science in Sports and Exercise, 36(5), Supplement abstract 155.

Well-trained Ss completed a high-intensity intermittent exhaustive exercise protocol on four occasions. The first trial was for familiarization purposes. During a five day intervention period, Ss repeated the exercise on days 1, 3, and 5. Before the familiarization trial, Ss consumed a moderate CHO diet (6 gm/kg). Throughout the intervention, Ss consumed a high-CHO diet (12 gm/kg). After the exercise, a 4 gm/kg supplement was consumed. Muscle biopsies were taken before, immediately after exercise, and three hours into recovery on each occasion.

Compared to baseline, pre-exercise glycogen was significantly higher on day 3, but not on day 5. Muscle glycogen utilization was also higher on day 3 when compared to days 1 and 5. Pre-exercise levels or utilization of intramuscular triacylglycerol were not affected by the CHO supplement. Performance was elevated on days 3 and 5.

Implication. It is not possible to produce CHO supercompensation by repeated high CHO supplements, but performance remains elevated as a result of extra CHO.

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