Major League Baseball concluded that reduced aerodynamic drag of the baseballs has contributed to a league-wide spike in home runs since the second half of the 2015 season. In other words, the physical properties of the balls themselves appear to have changed, reducing air resistance and allowing a ball to “carry” farther.
A team of 10 academics with expertise in engineering, physics and statistics conducted the analysis using Statcast data and high-tech testing of the balls themselves. The 84-page report released on Thursday determined that the change in drag was a key factor in the home run increase, although physical testing could not pinpoint a specific manufacturing alteration driving that change.