Dietary nitrate improves sprint performance and cognitive function during prolonged intermittent exercise

It is possible that dietary nitrate (NO 3 − ) supplementation may improve both physical and cognitive performance via its influence on blood flow and cellular energetics. Purpose To investigate the effects of dietary NO 3 − supplementation on exercise performance and cognitive function during a prolonged intermittent sprint test (IST) protocol, which was designed to reflect typical work patterns during team sports. Methods In a double-blind randomised crossover study, 16 male team-sport players received NO 3 − -rich (BR; 140 mL day −1 ; 12.8 mmol of NO 3 − ), and NO 3 − -depleted (PL; 140 mL day −1 ; 0.08 mmol NO 3 − ) beetroot juice for 7 days. On day 7 of supplementation, subjects completed the IST (two 40-min “halves” of repeated 2-min blocks consisting of a 6-s “all-out” sprint, 100-s active recovery and 20 s of rest), on a cycle ergometer during which cognitive tasks were simultaneously performed. Results Total work done during the sprints of the IST was greater in BR (123 ± 19 kJ) compared to PL (119 ± 17 kJ; P