Caffeine and dietary nitrate supplementation have both been shown to enhance performance in a single bout of endurance exercise. Caffeine acts at a central level to increase arousal and reduce the perception of effort during exercise, while nitrate supplementation acts at a peripheral level to enhance the efficiency of energy use during exercise. Both supplements enable individuals to exercise for longer periods and/or exercise at a higher intensity, which ultimately enhances performance in endurance exercise tasks. The respective research groups from Queenland Univ. (caffeine) and Exeter (nitrate) have conducted extensive investigations to explore and understand the effects of these supplements on acute exercise capacity and performance. 

High-intensity exercise training results in superior physiological adaptation, performance and health outcomes compared to moderate intensity training. Having inexpensive, safe and readily accessible nutrition interventions that could potentially facilitate individuals training at a higher intensity in each session is likely to have significant benefits in both clinical and athletic populations. Now novel and key understanding of the physiological mechanisms associated with any improved adaptation allow future nutrition and exercise training interventions to be designed to elicit the greater improvement in both health and performance.