Due to travel's disruptive effect on the body's normal circadian rhythm (24 hour biological clock), the effect of travel on athletic team performance is a topic of great interest to schedule-makers in professional sports.
The rule-of-thumb among sleep experts and neurologists is that for every time zone crossed, synchronization requires 1 day.
Conventional NFL wisdom says: 1) teams in the Pacific time zone are at a disadvantage when they play a game in the Eastern time zone; 2) Eastern time zone teams do not experience the same disadvantage when they travel to the Pacific time zone.
Do data support this conventional wisdom? Regular-season games from 5 recent NFL seasons (1280 games) were classified according to 2 variables: i) number of time zone changes and direction of travel experienced by visiting team, ii) whether the home team won or lost.
The number of time zone changes traveling West to East is indicated by a positive number; the number of time zone changes traveling East to West is indicated by a negative number.
For example, if the Seattle Seahawks (Pacific time zone) play the New York Giants (Eastern time zone) in New York, the game is assigned the value of +3; if the same teams play in Seattle, the game is assigned the value -3.
If the Denver Broncos (Mountain time zone) play the Chicago Bears (Central time zone) in Chicago, the game is assigned the value +1; if the same teams play in Denver the game is assigned the value -1.
Since 1966 the home team has won 57.3% of regular season NFL games.