Two weeks of watermelon juice supplementation improves nitric oxide bioavailability but not endurance exercise performance in humans

This 2016 randomized, double-blind, placebo-controlled crossover study investigated the effects of 16 days of watermelon juice supplementation on nitric oxide (NO) bioavailability and endurance exercise performance in eight healthy, recreationally active adult males. Participants consumed 300 mL/day of watermelon juice concentrate, providing approximately 3.4 g/day of L-citrulline, or an apple