Optimising a baseball's dimensions for improved throwing patterns in youth players

The baseball remains unchanged across age groups. This study investigated how ball size impacts throwing patterns to establish if youth players might benefit from using more appropriately sized balls. Throwing patterns for 79 participants (11 ± 2 years; 1.48 ± 0.18 m; 44.1 ± 16.2 kg) were video recorded for three different ball conditions: standard (ST), scaled (SC), and preferred (PR). Each ball was thrown three times into a target net set at 3 m, and a composite score for each was determined. 82.3% of participants preferred a ball smaller than ST, however, their preferred ball choice was not influenced by hand size (-2 Log likelihood = 233.676, χ²₍₁₎ = 2.44, p = .118). Total score was significantly higher for the PR compared to the ST ball (p = .015), and there was a notable main effect of ball size on the throw's stride component (p = .026). Ball size influenced throwing pattern, with the PR ball scoring highest amongst all three conditions. Since 82.3% of participants preferred a ball smaller than ST, there appears to be a strong case for using smaller balls for youth baseball. Doing so could prove advantageous to performance, and reduce the incidence of overuse injuries.