The good news for athletes is that circadian clocks can be tweaked. Dr. Brandstaetter says he deliberately alters his depending on what he plans to do, adjusting factors like light, activity and meal times. He normally does not get up early or late, but somewhere in between. But he makes himself an early riser for work and becomes a late riser when he is on vacation. He is now working with athletes, doing what he calls “circadian coaching.” The idea is to change the natural biological clocks of those who are naturally late risers when their sporting events — like marathons — start early in the day.
Of course, there is more to athletic performance than physiology, exercise researchers noted. “One of the biggest problems in athletic performance research is that we cannot replicate the highly motivated and competitive situations in the laboratory,” said Hirofumi Tanaka, an exercise researcher at the University of Texas in Austin.
Yet, he adds, “there is no question that circadian rhythms affect sports performance.” That is one reason athletes worry about jet lag, which can disrupt circadian rhythms “and become a performance killer.”
As for coaches and team owners, Dr. Smith said, “It would be handy to know the phenotype of all of your team members. You could predict who would be playing well at various times of day.”
“Chronomoneyball,” he quipped.