Do different warm-up protocols affect isometric explosive muscular contraction?

BACKGROUND: There is a general agreement in the physical education and coaching communities on the importance of warm-up (WU) prior to any physical performance. Nevertheless, the value of WU remains controversial among researchers. OBJECTIVE: The purpose of the study was to assess the effect of direct, indirect, and combined direct and indirect WU protocols (DWU, IDWU, and CWU, respectively) on knee extension rate of torque development (RTD). METHODS: Twenty-nine physical education students were tested for maximal isometric knee extension tests on an isokinetic machine following each of the WU protocols, as well as following a control condition of no WU. RTD index was calculated for 50, 100, 150, and 200 ms from the initiation of knee extension for each trial. RTD values following the four protocols were compared by repeated measures ANOVA for each of the temporal indices. RESULTS: None of the differences between the protocols' means was statistically significant at any of the temporal indices. Nevertheless, individual responses demonstrated that certain participants exhibited a non-uniform response profile, thus suggesting differential responses to alternate protocols. CONCLUSIONS: Within the limitations of the current protocol and outcome measures, it is recommended that practitioners experiment with different WU routines and adjust them on an individual basis.