Effect of using mechanical devices for baseball batting on warm-up decrement.

The extent to which different mechanical baseball-batting devices used during a rest affected performance immediately after rest (warm-up decrement) was examined. Difference scores between the average of prerest Trials 8, 9, and 10 and each of 10 postrest trials were used to determine the presence of warm-up decrement. It was predicted that the use of a batting-T and the Batter's Aid machine (in which a batter swings at a ball popped up within the strike zone) would result in superior performance measured as the distance (ft.) a ball was hit and frequency of contacts on postrest performance reducing or eliminating the warm-up decrement. Performance of 33 boys, aged 11 and 12 yr., indicated that only use of the Batter's Aid eliminated warm-up decrement with respect to both the distance and frequency as compared to the batting-T and control groups. In addition, the batting-T condition solicited significantly better performance than the controls on the distance measure but was statistically similar to the controls in frequency of contacts. Also, superior performance was significantly related to heightened heart rate, a physiological index of arousal. A primary explanation of the results focused on the effects of heightened physiological and psychological arousal on warm-up decrement.