Influence of different amounts of carbohydrate on endurance running capacity following short term recovery

This study examined the effect of ingesting different amounts of carbohydrate (CHO) during 4 h recovery (REC) from prolonged running, on subsequent endurance running capacity when subjects were fully rehydrated. Nine men ran at 70% (V)over dot O(2)max on a treadmill for 90 min (T1), followed by the REC and a run to exhaustion at the same speed (T2) on two occasions. Thirty minutes into REC, subjects ingested 50 g of CHO from a 6.5% CHO-electrolyte solution (CE) on both occasions. Thereafter, subjects ingested either the same CE or a placebo (PL) every 30 min for the first 3 h of REC. The total volume ingested was equal to 150% of the body mass lost during T1 which achieved rehydration during REC in both trials. Higher blood glucose and serum insulin concentrations (P<0.05) were observed during REC in the CE trial. Nevertheless, similar run times were achieved during T2 in both trials (CE: 56.9+/-8.1 min and PL: 65.4+/-7.8 min) (+/- S.E.M) (NS). Therefore, these results suggest that ingestion of 50 g of CHO immediately after prolonged exercise, and rehydration with a placebo solution, results in a similar endurance capacity, after a 4 h recovery, as ingesting 3 times more CHO (similar to 167 g CHO) over the same period.