Maltodextrin Ingestion Combined with Dietary Nitrate has No Additional Effects on Running Economy and Muscle Oxygenation during Prolonged Running.

The acute effects of maltodextrin (MD) ingestion combined with dietary nitrate (NO_3-) on running economy (RE), substrate oxidation, and muscle oxygenation during running were investigated. Ten male marathon runners participated in a double-blind crossover design, receiving either 1.5 g MD·kg^-1 BM (MD) or an isocaloric co-ingestion of 1.5 g MD·kg^-1 BM and 500 mg NO3-beverage (MDNO). Measurements were taken at various stages to assess RE, followed by a 60-minute run at 70% of VO₂ peak. The results showed no significant differences in RE, substrate oxidation, or muscle oxygenation between MD and MDNO. However, the respiratory exchange ratio (RER) was significantly lower during high-intensity prolonged running following MDNO compared to MD. In conclusion, acute co-ingestion of MD with dietary NO_3- may impact aerobic energy production but does not significantly affect RE or muscle oxygenation during high-intensity prolonged running. [ABSTRACT FROM AUTHOR]