Major League Baseball has seen a serious uptick in home runs over the past two seasons. In 2015, the league saw just over one home run hit on average per game. Last season, that jumped up significantly to 1.16 and it stands at 1.18 so far this season -- before summer, when more homers are typically hit. During the “steroid era,” the average peaked at 1.17 in 2000 but was mostly in the 1.10-1.14 area.
We’re not seeing outliers like Barry Bonds hitting 73 home runs anymore, but we are seeing the types of players who used to hit 10 home runs now hitting 20 homers (see: Freddy Galvis). For example, in 1999 and 2000, the league saw 100-plus players cross the 20-homer time for the first times in history at 103 and 102, respectively. Last season, 111 players did it for the third triple-digit season league-wide. We’re probably going to see it again this year, too.
With drug-testing as stringent as ever and penalties for testing positive stronger than ever, it’s unreasonable to think that the surge in power is due to players continuing to use performance-enhancing drugs. The most popular theory these days to explain the power surge is a juiced baseball.
Ben Lindbergh of The Ringer asked Major League Baseball about it and they shared their research on the matter. Lindbergh received an 11-page document which detailed the league’s testing methodology and the results. The tests measured the baseballs’ weight, circumference, and coefficient of restitution (elasticity). The results showed that current era baseballs are not noticeably different than baseballs in the past. The league also asked physics professor and baseball physics expert Alan Nathan to independently review their research. Nathan said, “I saw nothing in the data that was presented that suggests that the ball has been altered at all.”
So, that’s that. Both Lindbergh and Nathan are still stumped about the explanation for the power surge, but the data shows that it’s not due to juiced baseballs.