Using a lighter baseball would not significantly increase batted-ball impact injuries to position players in youth baseball, but would likely increase such injuries to pitchers, suggests a first-of-its-kind study.

Studying reaction time among youth baseball players ages 9 to 13 in laboratory tests intended to mimic game conditions, researchers reported that the 10% reduction in time to respond to a batted ball expected from reducing ball weight by 20% would lead to less than a 5% increase in impact probability to nonpitchers, but increase impact probability for pitchers by more than 25%.

Previous research indicated that either reducing the weight of a baseball or its stiffness could result in a decrease in injuries or injury severity, but the effect of reducing ball weight on the speed at which a ball comes off a bat had not been directly studied.