Carb-Protein Supplementation Enhances Cycling Performance
Researchers from Massey University, New Zealand, recently compared the effects of a high-carbohydrate diet and a high-carbohydrate diet plus supplemental protein on recovery parameters in cyclists during a period of hard training. The results of this new study provide further evidence of the superiority of carb-protein formulations for post-exercise nutrition.
Twelve trained cyclists completed three high-intensity rides over four days. On Day 1 they completed a 2.5-hour interval workout. On Day 2 and Day 4 they completed repeated sprint performance tests, and on Day 3 they rested. All of the cyclists maintained a high-carbohydrate diet throughout the study period. After each ride, half of the cyclists consumed a carbohydrate supplement and the other half consumed a carbohydrate-protein supplement. After a washout period, the protocol was repeated, but the recovery nutrition treatments were switch. Researchers measured nitrogen balance to determine whether the cyclists were in an anabolic or catabolic state. They also measured cortisol and cytokine levels to mark inflammation, creatine kinase to mark muscle damage, and malonyl dealdehyde to mark oxidative stress.
Nitrogen balance was positive on Day 1 in the carb-protein group and negative in the carb-only group. There were no significant between-group differences in cortisol, cytokines, creatine kinase, or malonyl dealdehyde. However, sprint performance was 4.1 percent better in the carb-protein group than in the carb-only group on Day 4. The authors of the study, which was published in Applied Physiology, Nutrition, and Metabolism, concluded, "A nutritive effect of post-exercise protein content was not discernible short term (15 h), but a delayed performance benefit (60 h) was observed following protein-enriched high-carbohydrate ingestion." |
