Effect of carbohydrate feeding during recovery from prolonged running on muscle glycogen metabolism during subsequent exercise

This study examined the effect of carbohydrate (CHO) intake during a 4 h recovery from prolonged running on muscle glycogen metabolism during subsequent exercise. On 2 occasions, 7 male subjects ran for 90 min at 70 % maximum oxygen uptake VO(2 max) on a motorized treadmill (R1) followed by a 4 h rest period (REC) and a 15 min run (R2) consisting of 5 min at 60 % and 10 min at 70 % VO(2 max) During REC, each subject ingested a total of 2.7 l of an isotonic solution containing either 50 g of CHO (LOW) or 175 g of CHO (HIGH). Biopsy samples were obtained from the vastus lateralis immediately after R1, REC and R2. During REC, a higher muscle glycogen resynthesis was observed in HIGH when compared with LOW trial (75 +/- 20 vs. 31 +/- 11 mmol x kg dry matter (dm) -1, respectively; p < 0.01). Muscle glycogen utilization during R2 was similar between the HIGH and LOW trials (39 +/- 10 vs. 46 +/- 11 mmol x kg dm -1, respectively). These results suggest that ingestion of a large amount of CHO at frequent intervals during recovery from exercise does not affect the rate of muscle glycogen utilization during subsequent exercise.