Participants ingested either ammonium chloride (0.15 g.kg^-1, ACID) or placebo (0.15 g.kg^-1, PLA) in four doses during the 24 h prior to the trial day.

<p>An 8 min warm-up (5 min at 40% of peak power output, 3 min at 60% of peak power output) was followed by 10 x 2 min intervals at 80% of peak power output, interspersed with 1 min of active rest at 40% of peak power output, performed on a cycle ergometer. Timings of additional supplementation, venous blood and muscle biopsy samples and a post-exercise meal are shown prior to and following the high-intensity interval session.