抄録
This study examined the effects of two tag-up start techniques in collegiate baseball by comparing baserunning times for a normal start and a rolling start. Twenty-two male collegiate baseball players participated. Running time from third base to home plate was measured with a wireless photoelectric timing system for two techniques: a conventional normal start and a rolling start adapted from softball. Mean running time was 3.74±0.14 s for the normal start (95% CI: 3.68－3.80 s) and 3.63±0.14 s for the rolling start (95% CI: 3.57－3.69 s). The rolling start was significantly faster than the normal start (t (21) =6.34, p < 0.01, Cohen’s d=1.35). The mean difference between techniques was 0.11±0.08 s (95% CI: 0.07－0.15 s), corresponding to a distance of 0.84±0.61m. These findings suggest that the rolling start is a viable option in tag up situations, as even the lower bound of the confidence interval (0.07s) represents a difference that could determine whether a run scores in a close play at home plate. However, the measurements were conducted under controlled conditions in which participants determined their own timing, and thus did not include the element of timing the departure to match the fielder's catch. Further research under game-like conditions is needed to determine whether the observed time reduction can be replicated in actual competition.
