Using Your Inner Clock to Up Your Batting Score New research suggests that sports players competing more in sync with their internal clocks might have a competitive, or circadian, advantage. W. Christopher Winter of the Sleep Medicine Center talks about how players can improve their odds of winning.
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Using Your Inner Clock to Up Your Batting Score

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Using Your Inner Clock to Up Your Batting Score

Using Your Inner Clock to Up Your Batting Score

Using Your Inner Clock to Up Your Batting Score

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  • <iframe src="" width="100%" height="290" frameborder="0" scrolling="no" title="NPR embedded audio player">
  • Transcript

New research suggests that sports players competing more in sync with their internal clocks might have a competitive, or circadian, advantage. W. Christopher Winter of the Sleep Medicine Center talks about how players can improve their odds of winning.

JOE PALCA, host:

This is Talk of the Nation: Science Friday from NPR News. I'm Joe Palca, sitting in for Ira Flatow. Later in the hour, we'll be talking about the ongoing battle to keep creationism out of public-school class, but first, sports and the circadian advantage. If you've ever traveled across a few time zones, and you know it takes a little while for your body to get in sync with the new schedule. And that jetlag could affect your performance, especially if you're an athlete, according to my first guest.

Chris Winter, medical director at the Martha Jefferson Hospital Sleep Medicine Center, and his colleagues, look back at nearly 20,000 Major League Baseball games, to see whether a time zone change for the players affected the outcome of the game. They found the teams playing in a time zone, they were in sync with, had a circadian advantage, and that made them more likely to win. The researchers - the research was presented this week at a meeting of the Associated Professional Sleep Societies.

Dr. Winter joins me now from Charlottesville, Virginia, to talk about the study. Welcome to Science Friday, Dr. Winter.

Dr. CHRIS WINTER (Medical Director, Sleep Medicine Center, Martha Jefferson Hospital): Thank you very much for having me.

PALCA: If you'd like to talk about this study, or maybe ask Dr. Winter a question about jetlag, or baseball, or we'll see what else, you're welcome to give us a call. The number is 800-989-8255. That's 800-989-TALK. And if you want more information about what we'll be talking about this hour, go to our website at - sorry,, where you'll find links to our topic. So, Dr. Winter, I mean, what is this? What is this thing about - what are we talking about, about a circadian advantage? What were you looking at?

Dr. WINTER: Well, I think that in the same way that individuals refer to a home-field advantage, we were - our question was, is there a circadian advantage that you can apply to games, in the same way you would in what's - you would a home-field advantage that would help predict one team's chances of winning versus another?

PALCA: I see. And so this is - so, we're talking about, is it either direction? I mean, if the Mets go to the Dodgers, is that just as bad as if the Dodgers would go to the Mets? Because I seem to remember a little ditty that's goes "east to west at your best, west to east do the least."

Dr. WINTER: That's - you asked two important questions there.

PALCA: OK, sorry. One at a time. Does it...

Dr. WINTER: First is that the circadian advantage does apply east-west , and west to east, and that was one thing that we looked at. One important difference our research - one important feature that our research used that had not been used previously was looking at teams throughout a season, and once a team started moving within the country, east to west, or west to east, really, their home-field affiliation goes out the window. For instance, once the Orioles leave the East Coast and travel out to the West Coast, after a period of acclimation, they become a West Coast team.

And the standard rule in sleep medicine is that for every time zone you change, either west to east, or east to west, it takes about 24 hours or a day to adjust. So, looking at these seasons, we were able to follow each individual team day by day, and track how far away they were from acclimation to their current time zone, or if they were acclimated, so we could look at some very interesting questions, once that data was accumulated. And one of them you alluded to was, what's the difference between east to west, and west to east?

What's very interesting about that is that we initially did this research as a pilot study, looking at only the 2004 baseball season. And when you look at that, there was clearly - it seemed to us at that time - an advantage for a team to be on the East Coast receiving a team having recently traveled from the West Coast. And it's important to realize that that could be the Orioles at home in Baltimore receiving a team traveling from the West Coast, or it could even be a West Coast team that had been on the East Coast for a period of time and had acclimated, and now is receiving a team - and now were - they were playing a team as an away team, but they were more acclimated to their time zone.

PALCA: I got it.

Dr. WINTER: So in 2004, we found that it was more difficult to travel west to east and play at your best. But when we looked at it over the last 10 years, which we were able to do through funding from Major League baseball, we actually found the opposite that it seemed to be more advantageous to be on the West Coast, receiving a team playing from the East Coast. So it would look to be harder traveling east to west versus west to east. And this probably has to do with a team performing closer to their circadian peak in these specific games.

PALCA: Got it. Now, how big in effect are we talking about? I mean, are they, you know - is this going to be a 50-percent increase in likelihood of winning, or a few percent, or what?

Dr. WINTER: It- the - that answer really depends on the magnitude of the advantage, and so, a home field advantage is just that. It's a static advantage. The differences between a home-field advantage and circadian advantage, every game played in the Major League baseball season, there is a home-field advantage. Somebody's playing at home. Somebody's away. When you look at circadian advantage of the 20 - of the 24,000 games that we looked, at give or take, about 19,000 of them featured teams at an equal circadian advantage.

So, only about a fifth of the season is there actually an appreciable circadian advantage. Now, of those 5,046 games during the ten years that we studied in which one team held an advantage over the other, the interesting thing about circadian advantage is there's magnitude of it. You can have a three-hour, two-hour or one-hour advantage over another team, because there are four time zones within the continental United States that we play within.

PALCA: Uh-huh.

Dr. WINTER: So the answer to your question is, it's probably a small advantage overall, particularly when you're comparing it to home-field advantage, but it is significant, particularly when you start getting into two- and especially three-hour advantages. And when you look through the season, you can find examples of a team perfectly acclimated to their time zone, whether this is a home team or the away team, playing against another team that have recently traveled across the country and now are three hours off.

PALCA: Uh-huh.

Dr. WINTER: So in that case, it can be as much as a 60-percent advantage.

PALCA: Right.

Dr. WINTER: And back in the 2004 season, there were 11 instances of that kind of advantage being present during that season, and of those 11 games, 10 of them were won by the team with the circadian advantage, irrespective of their home-field advantage.

PALCA: So again, the Lakers, if I can just use my NBA analogy, and the first game of the playoffs, where at the double disadvantage of having been disadvantaged circadian rhythm and playing in an away stadium...

Dr. WINTER: Exactly. And every day that goes by, the - a team like the Lakers are going to get a little bit more acclimated to the point where they're perfectly acclimated. So, you see trends in this as teams play one another for three- or potentially four-game stretches, that circadian advantage tends to dissipate as time passes, and perhaps the team with the better talent prevails.

PALCA: OK. We have time for one quick question, and let's go to Judith in Chico, California. Judith, welcome to Science Friday.

JUDITH (Caller): Yes. I'd like to know what advantage or disadvantage this may have for Olympian athletes, depending how early they can arrive at the Games or...

PALCA: Yeah, good question, because that's a long - yeah. Go ahead.

Dr. WINTER: That's a fantastic question. Now, we're dealing with circadian time-zone travel that's beyond just the four time zones in the continental United States. So, this is a lot of the research that we do, and a lot of the assistance we provide to teams, in terms of how can they overcome these travel disadvantages?

And the Olympics are really a unique situation, A, because they're being played in China, which is a tremendous circadian adjustment that these athletes are going to have to make. And one way, the color (unintelligible) was to simply get there early, for the Olympians to actually travel to Beijing, and actually adopt their schedule, and try to get acclimated before they start their competition. Some more wealthy countries are able to do this.

Other times, travel's more restricted, and so teams have to adjust to the new time zone while still within their old. So this is the law, the assistance we can help provide athletic teams or individual athletes, by coming up with strategies where they can adjust to a time zone they're going to play in in the future, while still in their current time zone. But these are very sought after strategies that the teams look for, because in the Olympics, as in baseball and these other sports, the smallest advantage can pay big dividends.

PALCA: OK, well, Dr. Winter, we have to leave it there. Thanks very much for speaking with us.

Dr. WINTER: You're welcome. Thank you for having me.

PALCA: Chris Winter is Medical Director at the Martha Jefferson Hospital Sleep Medicine Center in Charlottesville, Virginia. And he was - we were talking with him on his new study on baseball and circadian rhythms.

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