Caffeine ingestion increases endurance performance of trained male cyclists when riding against a virtual opponent without altering muscle fatigue.

Purpose: Caffeine improves cycling time trial (TT) performance; however, it is unknown whether caffeine is ergogenic when competing against other riders. The aim of this study was to investigate whether caffeine improves performance during a 4-km cycling TT when riding against a virtual opponent, and whether it is associated with increased muscle activation and at the expense of greater end-exercise central and peripheral fatigue.

Methods: Using a randomized, crossover, and double-blind design, eleven well-trained cyclists completed a 4-km cycling TT alone without supplementation (CON), or against a virtual opponent after ingestion of placebo (OP-PLA) or caffeine (5 mgkg, OP-CAF).

Physiological, Perceptual, and Affective Responses to Six High-Intensity Interval Training Protocols.

This study examined the extent to which different high-intensity interval training (HIIT) and sprint interval training (SIT) protocols could influence psychophysiological responses in moderately active young men. Fourteen participants completed, in a randomized order, three cycling protocols (SIT: 4 × 30-second all-out sprints; Tabata: 7 × 20 seconds at 170% ⋮O; and HIIT: 10 × 60 seconds at 90% HR) and three running HIIT protocols (4 × 4 minutes at 90%-95% HR, 5 × at v⋮O, and 4 × 1,000 meters at a rating of perceived exertion (RPE) of 8, from the OMNI-Walk/Run scale). Oxygen uptake (⋮O), heart rate, and RPE were recorded during each interval.