Abstract
BACKGROUND: Warm-up intensity is considered a key factor influencing acute physical performance, yet its specific effects on explosive power and agility in university football players remain unclear. This study compared the acute effects of low-, moderate-, and high-intensity warm-up on lower-limb explosive power and agility. METHODS: Twenty male university football athletes completed three 15-min warm-up protocols differing in intensity. Performance was assessed using the standing triple jump (STJ), 10 m sprint, 505 test, and T-test at pre-, post-, and post-10. Generalized mixed linear models were applied to evaluate the effects of intensity and time, with results reported as standardized effect sizes (ES) and 90% confidence limits (CL). RESULTS: The 10 m sprint performance was substantially better after the low-intensity warm-up than the moderate-intensity (ES; ± 90% CL: Post: 1.93; ± 0.64; Post-10: 3.31; ± 0.45) and high-intensity (Post: 1.90; ± 0.64; Post-10: 3.56; ± 0.65) warm-ups. The 505 test also showed superior performance after the low-intensity warm-up (vs. moderate: 1.55; ± 0.74, 1.16; ± 0.44; vs. high: 3.15; ± 0.72, 1.24; ± 0.44). Notably, in the 505 test (post: 1.6; ± 0.7; post-10: trivial), performance following the moderate-intensity warm-up at post was also substantially superior to that following the high-intensity warm-up. The T-test demonstrated a similar advantage (vs. moderate: 0.95; ± 0.23, 0.78; ± 0.22; vs. high: 0.86; ± 0.23, 0.73; ± 0.22). In contrast, the STJ (vs. low, post: 0.66; ± 0.31; post-10: 0.51; ± 0.31) improved only immediately after the moderate- and high-intensity warm-ups. CONCLUSION: Low-intensity warm-up produced the most consistent and sustained improvements in sprint and agility performance. Moderate-intensity warm-up showed only a brief advantage in the 505 test, whereas high-intensity warm-up generally impaired speed and change-of-direction performance, with any explosive power gains being short-lived. These findings identify warm-up intensity as a key determinant of pre-competition readiness in male university football athletes.