The purpose of this study was to determine the effects of weighted bat training on bat swing velocity. Sixty male university baseball players volunteered to participate and were randomly assigned to one of three equal-sized training groups: batting practice (BP), dry swing (DS), and control. The BP hit live pitched baseballs with alternated overweighted, underweighted, and standard 30-oz bats for 12 weeks. The DS dry-swung with alternated overweighted, underweighted, and standard bats. The control group dry-swung with a standard bat during the 12 weeks. All three groups showed significant increase in bat swing velocity during the study (p < 0.05). Furthermore, the differences between pre- and posttest scores (delta scores) were significant between BP and control, between DS and control, and between BP and DS (p < 0.05). It is suggested that training with variable weighted implements will significantly increase bat swing velocity, and that the use of loads specific to the target activity but with sufficient variation about the standard load will induce further training adaptations.
(C) 1995 National Strength and Conditioning Association