The Wall Street Journal reports that weighted bats don’t quicken a batter’s swing — but we’ve known that for decades:
“With 20 college baseball players from one university, I found no difference,” said Dr. Szymanski, who referred to the number of players he studied with 10 differently weighted bats. “Their performance was statistically unchanged.”
Other studies, notably those by Dr. DeRenne, have found that warming up with an overloaded bat, especially with a doughnut, slowed down batters.
“The doughnut is the worst,” said Dr. DeRenne, who tested one weighing 28 ounces. “It changes the balance point in the bat.”
The weight may alter the batter’s swing, especially in younger players who are still developing strength and mechanics.
Sport Science, a television series where athletes and scientists explore the biomechanics of different sports activities, tested the effect with a college player in 2008. Without any added weight, the batter averaged 69 mph on 10 swings and routinely connected with the bat’s sweet spot on balls pitched from a machine. After warming up with a doughnut, the batter’s speed decreased to 68.3 mph on average, and on each swing, the ball missed the bat’s sweet spot by several inches.
The experience of a lone batter in a single test can’t be generalized to others, but the results resembled other studies.