Szymanski, D. J., Boyce, D. C., Beam, J. R., & Greenwood, M. (2014). Effect of warm-up devices on bat velocity, and perception of heaviness and speed of swing. Medicine & Science in Sports & Exercise, 46(5), Supplement abstract number 923.

This study examined the effect of various warm-up devices on bat velocity and the perception of heaviness and speed of swing of Division I collegiate softball players (N = 16). Ss were randomly placed into one of six groups to swing six different warm-up devices ranging from 425.2 to 1814.4 g over six days. On-deck-circle warm-up device velocity was recorded. Immediately after the warm-up swings, Ss subjectively rated the heaviness of the warm-up device relative to the standard softball bat (83.8 cm, 652.0 g). Once in the batter’s box, standard softball bat velocity was recorded. Immediately after each swing, Ss subjectively rated how fast they swung the standard softball bat. The testing order of the warm-up devices was randomly assigned to each group. Each S was tested over six days, using a different device each day.

There was a significant difference between all devices’ warm-up swing velocities compared to the standard softball bat warm-up swing velocity. There was a significant within-subjects main effect for the warm-up opinion of “heaviness of bat”. After comparing each value to the standard softball bat heaviness rating, all warm-up devices had significantly different ratings than the standard bat’s heaviness rating. There was no significant difference between the mean standard softball bat velocities after using any of the six warm-up devices. The only significant within-subjects main effect for the “speed of swing” rating compared to the standard bat was the 77.5 cm, 1814.4 g device.

Implication. Although all warm-up devices’ warm-up swing velocities were different when compared to that of the standard softball bat in the on-deck circle, Ss also felt different than the standard bat. Warm-up devices varying from 425.2 to 1814.4 g did not significantly change mean standard softball bat velocity for collegiate softball players. Based on bat velocity, players can use any six warm-up devices in the on-deck circle and maintain their bat velocity while swinging a standard softball bat. Any advantage of the warm-up with a weighted device was thus psychological and not physiological. Warm-up devices appeared to have no effect on standard softball bat velocity.

[Editor’s note: It would have been better to have a no-warm-up device control as a seventh group.]

Return to Table of Contents for this issue.