The effect of on-deck warm-up routines in baseball on bat velocity, muscular activity and intensity in time-frequency space

Abstract

The purpose of this study was to determine how using warm-up implements of di_erent weight a_ects post warm-up baseball bat velocity. Furthermore muscular timing (on-o_) and intensity in time-frequency space and thus fatigue were investigated in order to find relations to bat velocity. Four male amateur baseball players participated in this study. On three separate days each subject completed one of three on-deck warmup conditions (standard (SC), heavy (HC), light (LC)). After each warm-up routine the subjects hit at least five balls with a wood-composite bat (SC). Bat velocity and muscular activity of 16 muscles (8 bilateral) of the upper and lower body were measured. All sEMG data were analyzed for muscular timing using on-o_ calculations and for intensity in time-frequency space using wavelet analysis. Bat velocity was significantly highest after LC 31:58_6:78ms_1. Lowest bat velocity was recorded after SC 22:66_4:72ms_1. A muscular recruitment pattern from the lower to the upper extremity according to the kinetic link principle was not retraced. Analysis of the time-frequency domain showed no significant changes in the power spectra after the three warm-up conditions. Hence any indication of muscular fatigue was not detected.