Right-handed baseball players more successful when batting left-handed

The study, published in the New England Journal of Medicine, reanalyzed data from a similar study released in 1982, and used new data from every major league baseball player from 1871 through 2016. According to the new findings, the advantage of throwing right-handed but batting left not only increases the likelihood of players becoming professional players, but also improves a professional player's likelihood of being one of the top hitters in the Major League.

David Mann, from the Vrije Universiteit Amsterdam: "Baseball players who adopt a left-handed stance enjoy a range of potential benefits, but the players who bat left and throw right-handed have a very large and additional advantage when batting."

Only 2% of the general population throws right-handed and bats left, yet 12% of Major League players throw right and bat left. Incredibly, 32% of the best ever major league batters throw right and bat left. This suggests that right handers who adopt a left-handed stance have a greater chance of becoming a very good professional batter. The research team conjecture that players who throw right-handed and bat left enjoy a biomechanical advantage, with the dominant (throwing) hand being placed further from the hitting end of the bat, providing a longer lever with which to hit the ball.

Previous research reanalysed

In 1982, scientists John McLean and Francis Ciurczak claimed in a letter published in the New England Journal of Medicine that baseball players who bat and throw left-handed should have an advantage when batting because they possess less hemispheric lateralization than right-handed people, meaning that the functions of the right and left brain hemispheres are less likely to differ in left-handers. In baseball this would have meant that a lack of lateralization provides a relative advantage to batters who both throw and bat left-handed.

McLean and Ciurczak found an overrepresentation of players who bat left in professional baseball, relative to lesser-skilled controls, and higher batting averages among professionals who throw left-handed and bat left than among those who throw right-handed and bat left or those who throw right-handed and bat right. However, the current reanalysis by David Mann (Vrije Universiteit Amsterdam), Florian Loffing (University of Oldenburg) and Peter Allen (Anglia Ruskin University) shows an oversight that supports the opposite conclusion.