Effect of an isocaloric carbohydrate-protein-antioxidant drink on cycling performance.
OBJECTIVE
Fourteen male cyclists were studied to compare the effect of carbohydrate-protein-antioxidant beverage (CHOPA) to an isocaloric carbohydrate-only (CHO) beverage on time to fatigue and muscle damage.


METHODS
Subjects performed two sets of rides to exhaustion on a cycle ergometer. In each set, the first ride was performed at 70% VO2peak, and the second was performed 24 h later at 80%. CHO or CHOPA was consumed every 15 min during exercise and immediately afterward. Plasma CK and LDH and muscle soreness were measured pre- and postexercise.


RESULTS
Time to fatigue was not different between CHO and CHOPA at 70% VO2peak (95.8 +/- 29.7 vs 98.1 +/- 28.7 min), 80% VO2peak (42.3 +/- 18.6 vs 42.9 +/- 21.8 min), or total performance time (138.1 +/- 39.3 vs 140.9 +/- 43.7 min). Postexercise CK was increased (P < 0.05) from baseline in CHO (203 +/- 120 vs 582 +/- 475 U.L(-1)) but not with CHOPA (188 +/- 119 vs 273 +/- 169 U.L(-1)). Similarly, LDH values increased over baseline in CHO (437 +/- 46 vs 495 +/- 64 U.L(-1)) but not with CHOPA (432 +/- 40 vs 451 +/- 43 U.L(-1)). Postexercise CPK and LDH were higher after the CHO trial than after the CHOPA trial. Median postexercise muscle soreness was higher in CHO (3.0 +/- 5.0) than with CHOPA (1.0 +/- 3.0).


CONCLUSIONS
No differences in time to fatigue were observed between the beverages, despite lower total carbohydrate content in the CHOPA beverage. The CHOPA beverage attenuated postexercise muscle damage, as evidenced by CK and LDH values, compared with an isocaloric CHO beverage.
Romano-Ely
Brett C
BC
Department of Kinesiology, James Madison University, Harrisonburg, VA 22807, USA.
Todd
M Kent
MK
Saunders
Michael J
MJ
Laurent
Thomas St
TS
D000293:Adolescent; D000328:Adult; D000975:Antioxidants / Q000494:pharmacology*; D001628:Beverages; D003402:Creatine Kinase / Q000097:blood; D004040:Dietary Carbohydrates / Q000494:pharmacology*; D004044:Dietary Proteins / Q000494:pharmacology*; D019587:Dietary Supplements; D005080:Exercise Test / Q000187:drug effects; D006801:Humans; D007770:L-Lactate Dehydrogenase / Q000097:blood; D008297:Male; D018482:Muscle, Skeletal / Q000293:injuries / Q000378:metabolism; D010807:Physical Endurance / Q000187:drug effects* / Q000502:physiology; D005082:Physical Exertion / Q000187:drug effects / Q000502:physiology
D000975:Antioxidants; D004040:Dietary Carbohydrates; D004044:Dietary Proteins; D007770:L-Lactate Dehydrogenase; D003402:Creatine Kinase