The final outcome of any sporting event may come down to whether the scheduling of the game aligns -- or doesn't -- with the internal biological body clocks of the athletes taking part, a study found.
Athletes and their coaches might want to take note and consider adjusting their wake-sleep schedules to take that into account, the researchers from the University of Birmingham in England say.
The performances of competition-level athletes can vary during the passing hours of a day by as much as 26 percent, they say.
"If a one percent difference in performance can make the difference between 1st place and 4th place in a 100 meter race and actually win you the gold medal at the Olympics, then imagine what a 26 percent difference in your performance could give you," says researcher Roland Brandstaetter. "Our research takes us away from the idea of 'time of day of the race' and directs us more to internal biological time."
Some earlier studies had suggested athletes generally perform best in the evening, but they didn't take into account whether an individual athlete was a "night owl" or a "morning person," the researches say.
That matters because there are detectable physiological differences in people linked to their natural wake/sleep patterns, they say.
For the study, they looked at 20 athletes whose circadian rhythms tagged them as early, intermediate or late types, and tested and recorded their cardiovascular endurance at six different times of the day.
Considerable variations in individual performance in standard fitness tests were seen throughout the day, the researchers report in the journal Current Biology.
The best predictor of performance at any particular hour turned out to be the time elapsed since their normal and preferred wakeup time, the study found.
While an early riser might be at a peak performance level in the early afternoon, an athlete who prefers sleeping late could hit their peak much later at night, the scientists say.
Early risers tended to reach their peak around noon, intermediate type around 4 p.m., and night owls -- or late risers -- don't reach their best performances until around 8 p.m., they found.
While genetics determines what kind of body clock -- early, intermediate or late -- you possess, they can be adjusted or synchronized to the environment, the researchers say.
So noting what time a competition is to take place, and adjusting your wake-sleep cycle to put your own peak at the proper time, could make the difference between winning and losing, they suggest.
"Obtaining a personal best performance is on everyone's agenda, but how to do it, now that is a different question," says study co-author Elise Facer-Childs.
