ISTANBUL, Turkey — Who’s going to win the NBA championship? The answer may have more to do with jet lag than the stars on the court!
Although basketball fans typically look at injury history, team performance, and other statistics before placing a bet on the NBA playoffs, one crucial factor that is often overlooked is time zone changes. Scientists have found that playing a game in a different time zone can disrupt an athlete’s biological clock, leading to increased fatigue and potentially affecting their chances of winning. Moreover, the impact appears to give teams in the Western Conference an advantage in the NBA Finals.
“One of the most important results of this research for the home games of the NBA teams is that while traveling to the west increases the performance, traveling to the east decreases the performance,” says Firat Özdalyan, a sports physiology expert from Dokuz Eylül University in Turkey in a media release.
During the regular season, basketball players often travel across the five U.S. time zones for road games, an action that can be physically and mentally taxing. The study authors analyzed 25,016 NBA games across 21 seasons. They found a nearly 10-percent higher winning percentage among home teams in the Western time zone when they played against teams from the Eastern time zone (63.5%) compared to when Eastern Conference teams hosted western NBA teams (55%).
The findings, published in Chronobiology International, also give a more scientific explanation for why traveling across certain time zones makes a difference when it comes to winning and losing. Teams tend to win more home games when their circadian rhythm — the biological clock that regulates sleep-wake cycles — is ahead of local times.
For example, let’s look at what happens if the Los Angeles Lakers played an away game at Miami, sitting three hours ahead in the Eastern time zone, and then returned to Los Angeles for a home game. Researchers found that the player’s circadian rhythm would be ahead of the local time zone, making the Lakers sharper and more alert during their next home game.
Conversely, basketball teams often played worse when their circadian rhythms were behind the local time of their home arena. With all this in mind, study authors say the results could help basketball coaches prepare for the effects of time zone travel as they prepare for road games.
“Home teams who will be exposed to such a [circadian rhythm] phase shift (traveling from west to east) should be mindful of these potential performance detriments when constructing game plans,” adds Özdalyan. “It can be suggested that coaches (of away teams) should bear this (the low shooting success) in mind during the game preparation period.”
Circadian rhythms tell the body when it’s time to be awake and when it’s time to rest. Moving your regular bedtime and wake-up times, known as a circadian rhythm phase shift, can cause your body clock to be out of sync with the environment. Since your circadian rhythm needs 24 hours to adapt to every one-hour time zone change, people with out-of-sync internal clocks experience sleeplessness, daytime fatigue, and mental fogginess.
The study calculated the circadian rhythm phase shifts of teams who played in NBA games from 2000 to 2021. The review included data on the date of games, the final score, location, and which team was home or away. Additionally, researchers recorded the time zones of cities to calculate circadian phase shifts for each team.
In addition to the findings, the authors note that anaerobic performance (breaking down glucose for energy) could influence why home teams who travel from east to west do better. What’s more, the body clock adapts more easily to a longer rather than shorter day. The day is longer when traveling east to west and since the circadian rhythm is slightly longer than 24 hours, this means basketball players are traveling in the direction their bodies want to go.
