Reducing muscle temperature drop post warm-up improves sprint cycling performance

PURPOSE: This study aimed to determine the effect of passive insulation versus external heating during recovery following a sprint specific warm up on thigh muscle temperature and subsequent maximal sprint performance. METHODS: On three separate occasions, 11 male cyclists (age 24.7 ± 4.2 years, height 1.82 ± 0.72m, body mass 77.9 ± 9.8 kg; mean ± S.D.) completed a standardized 15 min intermittent warm up on a cycle ergometer, followed by a 30 min passive recovery period before completing a 30 sec maximal sprint test. Muscle temperature was measured in the vastus lateralis at 1, 2 and 3 cm depth prior to and following the warm up and immediately before the sprint test. Absolute and relative peak power output was determined and blood lactate concentration was measured immediately post-exercise. During the recovery period participants wore a tracksuit top and either i) standard tracksuit pants (CONT); ii) insulated athletic pants (INS) or; iii) insulated athletic pants with integrated electric heating elements (HEAT). RESULTS: Warm up increased Tm by approximately 2.5°C at all depths, with no differences between conditions. During recovery, Tm remained elevated in HEAT compared to INS and CONT at all depths (p<0.001). Both peak and relative power output were elevated by 9.6% and 9.1% respectively in HEAT compared to CONT (both p<0.05). The increase in blood lactate concentration was greater (p<0.05) post sprint in HEAT (6.3 ± 1.8 mmol/L) but not INS (4.0 ± 1.8 mmol/L) vs. CONT (4.1 ± 1.9 mmol/L). CONCLUSION: Passive heating of the thighs between warm up completion and performance execution using pants incorporating electrically heated pads can attenuate the decline in Tm and improve sprint cycling performance.