A warm-up strategy with or without voluntary contraction on athletic performance, lower-leg temperature, and blood lactate concentration.

It is unclear whether temperature-related warm-up effects can be accomplished by passive warm-up (e.g., by external heat). Therefore, this study compared the effects of two different warm-up protocols with and without voluntary contraction on subsequent sprinting and jumping performance. Eighteen healthy male collegiate students (23.3 ± 2.4 years, 173.8 ± 7.2 cm, 70.5 ± 9.3 kg) randomly experienced 10 min of active (jogging on a treadmill; belt speed: 9.0 km/h at a 1% incline) and passive warm-up (lying down in the warm-up chamber; inner ambient temperature set at 35°C) protocols, followed by ten sets of intermittent exercises in two separate sessions. Athletic performance, lower-leg muscle temperature, and blood lactate concentration were statistically compared using analysis of variance with Tukey-Kramer post-hoc comparisons. Cohen's d effect sizes (ES) were also calculated. There was no warm-up protocol effect over time on 20 m sprint times (condition × time: F9,323 = 1.26, p = 0.25). Maximal vertical jump heights were different (condition × time: F9,323 = 2.0, p = 0.04) such that subjects who performed the active warm-up protocol jumped higher (51.4 cm) than those who did the passive warm-up (49.2 cm, p = 0.04). There was a warm-up protocol effect over time on lower-leg muscle temperature (condition × time: F12,425 = 13.99, p<0.0001) in that there was a 5.5% and 5.8% increase after active (32.8 to 34.6°C, ES = 2.91) and passive (32.9 to 34.9°C, ES = 3.28) warm-up protocols, respectively. Blood lactate concentration was different (condition × time: F2,85 = 3.61, p = 0.03) since the values at the post-warm-up measurements were different between warm-up conditions (active: 4.1 mmol/L; passive: 1.5 mmol/L, p = 0.004, ES = 1.69). Subsequent sprint and jump performance did not differ between the duration- and muscle temperature-matched active and passive warm-up protocols. Non-thermal effects from the warm-up activity may be minimal for sprinting and jumping performance in recreationally active males.

Competing Interests: The author(s) have declared that no competing interests exist.

(Copyright: © 2024 Lee et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)