This story was written by Raisa Bruner and originally appeared on Travel + Leisure.
A new study out in the Proceedings of the National Academy of Sciences takes stock of 20 years of travel data from Major League Baseball teams with an intriguing conclusion: Jet lag effects were “largely evident after eastward travel with very limited effects after westward travel.”
So those L.A. to New York red-eyes really could take a toll, as it turns out.
The study considered 46,535 games, from 1992 to 2011, narrowing it down to games in which instances of east-west jet lag of at least two hours would be present for one of the teams—so about 5,000 games qualified.