The current study investigated the effect of caffeine on the breathing pattern during a high-intensity whole-body exercise.Using a randomized, crossover, counterbalanced, and double-blind design, twelve healthy men ingested either 5 mg.kgCaffeine 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 0.05). Compared to task failure with placebo, task failure with caffeine intake was marked by higher (p 0.05) minute ventilation (134.8 ± 16.4 vs. 147.6 ± 18.2 L.minIn conclusion, ingestion of caffeine alters the breathing pattern by increasing tidal volume and lengthening the inspiratory phase of the respiratory cycle. These findings suggest that caffeine affects the ventilatory system, which may account, in part, for its ergogenic effects during high-intensity whole-body exercises.