Time zones and tiredness strongly influence NBA results, study of 25,000 matches shows

The body clock has a big impact on the performance of NBA players, in response to study published within the peer-reviewed journal Chronobiology International.

The authors say their findings, from greater than 25,000 matches, show elite basketball coaches and teams should consider the physical and mental effects of time zone travel when planning games and preparing for games.

A primary of its kind, the research relies on the achievements at home and away of NBA (National Basketball Association) league players across 21 consecutive seasons. Considered probably the most competitive on this planet, NBA athletes continuously travel to matches across the five US time zones utilized by NBA teams.

The findings show that there’s a near 10% higher win ratio difference for home teams from the western time zone area (PDT) when playing against a team from the eastern EDT time zone, in comparison with when an EDT team hosts a PDT team.

  • When PDT teams play at home against EDT teams the winning percentage is 63.5%.
  • When EDT teams host a PDT team, the winning percentage drops to 55.0%.

As well as, the findings also show that teams win more home games when players’ sleep-wake cycles — linked to their circadian rhythm (CR) — are ‘ahead’ of the local time. That is after they’ve returned west from competing in a city further east where the local time is earlier.

For instance, if the LA Lakers play an away match at Miami (EDT) after which return to Los Angeles (PDT) to play a house game without much CR adaptation time (CR is ahead of the local time), the Lakers play the following home game with a CR advantage against whomever their opponents are.

Teams don’t have the identical success when players’ internal body clocks are either behind or synchronized with the local time where their home arena or stadium relies, in response to the outcomes.

Experts from Dokuz Eylül University and Yildiz Technical University, in Turkey, led the study. Dr Firat Özdalyan, a Sport Physiology expert from Dokuz Eylül, explains that they found NBA teams have to develop into used to the local time once they play away games to perform well.

“One of the crucial necessary results of this research for the house games of the NBA teams is that while traveling to the west increases the performance, traveling to the east decreases the performance,” he states.

“One other notable finding is that the success of NBA teams increases once they are fully adapted to the local time for away games.

“Home teams who might be exposed to such a CR phase shift (traveling from west to east) ought to be mindful of those potential performance detriments when constructing game plans.

“It could possibly be suggested that coaches (of away teams) should bear this (the low shooting success) in mind throughout the game preparation period.”

A circadian rhythm (CR) is the body’s sleep-wake pattern over a 24-hour day. A CR phase shift means bedtime and wake-up times move earlier or later within the day.

This implies the body clock gets out of sync with the environment which may result in sleeplessness, daytime tiredness and other issues. The body clock needs 24 hours to adapt for each one-hour time zone change.

The study investigated the effect of a CR shift on the performance of skilled NBA athletes.

Data was analyzed from 25,016 regular games across 21 consecutive seasons between 2000 to 2021. Information included the date, location, game result and residential or away team. Time zones of the cities where all games were played were identified to calculate the CR phase shifts of the teams.

The expert team say teams within the Pacific time zone can have a bonus in regular season home games similar to the Los Angeles Lakers, Portland Trail Blazers, and Seattle Supersonics.

Anaerobic performance could explain why home teams who travel from east to west do higher, say the authors. This sort of activity which is crucial for scoring, defending and other feats peaks later within the day.

The authors add that the body clock adapts more easily to an extended reasonably than a brief day. The day becomes longer traveling east to west and a natural circadian rhythm is barely longer than 24 hours. So this implies basketball players are traveling within the direction their bodies wish to go.

As for away teams, the authors say that travel fatigue is more likely accountable for poor performance than phase shifts in CR.

Players who’ve rest time between games or haven’t traveled across time zones for an away match are more capable of synchronize their body with the local time. As such, they aren’t as drained and play higher.

A limitation of this research is that the traveling schedules of the teams aren’t known. Since this information was not available, it was impossible to find out how long the teams stayed wherein city/time zone; how much they adapted to the local UTC; and what extent they were exposed to a CR phase shift with real data. Subsequently, the team used a predictive model for the traveling plans and CR adaptations of the teams by following the principles determined by previous research.

One other limitation is that the games weren’t separated in response to teams’ ability differences.