Cycling-based repeat sprint training in the heat enhances running performance in team sport players.

Applying heat training interventions in a team sports setting remains challenging. This study investigated the effects of integrating short-term, repeat sprint heat training with passive heat exposure on running performance and general conditioning in team sport players. Thirty male club-level Australian Football players were assigned randomly to: Passive + Active Heat (PAH; n=10), Active Heat (AH; n=10) or Control (CON; n=10) to complete 6 x 40 min high-intensity cycling training sessions over 12 days in 35 degrees C (PAH and AH) or 18 degrees C (CON), 50% RH in parallel with mid-season sports-specific training and games. Players in PAH were exposed to 20 min pre-exercise passive heat. Physiological adaptation and running capacity were assessed via a treadmill submaximal heat stress test followed by a time-to-exhaustion run in 35 degrees C, 50% RH. Running capacity increased by 26 +/- 8% PAH (0.88, +/-0.23; standardised mean, +/- 90% confidence limits), 29 +/- 12% AH (1.23, +/-0.45) and 10 +/- 11% CON (0.45, +/-0.48) compared with baseline. Both PAH (0.52, +/-0.42; standardised mean, +/- 90% confidence limits) and AH (0.35, +/-0.57) conditions yielded a greater improvement in running capacity than CON. Physiological and perceptual measures remained relatively unchanged between baseline and post-intervention heat stress tests, within and between conditions. Where thermal adaptation is not a direct priority, short-term, repeat effort high-intensity cycling in hot conditions combined with sports-specific training can further enhance running performance in team sport players. Six heat exposures across 12-days should improve running performance while minimising lower limb load and cumulative fatigue for team sports players.