Caffeine alters the breathing pattern during high-intensity whole-body exercise in healthy men

Purpose The current study investigated the effect of caffeine on the breathing pattern during a high-intensity whole-body exercise. Methods Using a randomized, crossover, counterbalanced, and double-blind design, twelve healthy men ingested either 5 mg.kg −1 of caffeine or cellulose (placebo) one hour before performing a high-intensity whole-body exercise (i.e., work rate corresponding to 80% of the difference between the gas exchange threshold and maximal oxygen uptake) until the limit of tolerance. Ventilatory and metabolic responses were recorded throughout the trial and at task failure. Results Caffeine ingestion increased time to task failure in relation to the placebo (368.1 ± 49.6 s vs. 328.5 ± 56.6 s, p = 0.005). Caffeine also increased tidal volume and inspiratory time throughout the exercise ( p