0009 Circadian Athletic Performance Variations When Travelling in the Canadian Football League

Abstract

Abstract Introduction Previous studies have shown a circadian disadvantage in professional sports with teams traveling westward. This effect has been attributed to the circadian clock, core body temperature and associated decline in sports performance in the evening. Compared to the National Football League (NFL) teams, Canadian Football League (CFL) teams often travel longer distances and play at later times. As such, the objective of the present study was to investigate the circadian disadvantage in the CFL. Methods Data from 5 years of CFL regular season games were extracted from online databases (2016-2021). Wins, score differentials, first downs, average total, passing, penalty, and kickoff yards, pass completion percentages, interceptions, fumbles, sacks, and time of possession were extracted for both the offense (made) and defense (allowed) for every away evening game (after 6pm; n=387) as well as the direction of the travel (eastward, same time-zone, westward). Two-way ANOVAs of Direction of Travel (eastwards, same time-zone, westwards) on each performance variable were computed to study the circadian effect. Linear regression analyses were done to investigate the effect of the distance travelled by the away team (longitude travelled) on each performance variable. Results Significant effects of travel were found for team variables: score differentials (F[2,386]=3.86, p=.02) and time of possession (F[2,386]=5.42, p=.005). Significant results were also found for offensive variables: first downs (F(2,386)=2.91, p=.06), average kickoff return yards (F[2,386]=3.54, p=.03), fumbles (F[2,386]=2.38, p=.09), and for defensive variables: first downs allowed (F[2,386]=2.79, p=.06), average yards per play (F[2,386]=4.83, p=.008), average passing yards allowed (F[2,386]=3.14, p=.04), average kickoff yards allowed (F[2,386]=3.37, p=.04). Each significant post-hoc t-test revealed a circadian disadvantage to teams travelling westwards and a circadian advantage for teams travelling eastwards. Linear regression analyses showed that traveling westward predicts worst performances on some variables, with an increasing effect with distance travelled. Conclusion These results are consistent with previous findings showing that professional sports teams travelling westward show important challenges in evening games. In addition, our results highlight the fact that this disadvantage may affect not only the result of the games, but also the performance of players at a more individual level. Support (if any)