Time Is On Your Side

If you run 10Ks or swim competitively, you're used to racing
against the clock. But you may be overlooking another timekeeper that
plays a key role in athletic performance: your body's circadian rhythms.
Nearly every physical attribute, from strength to flexibility, grows more
potent over the course of a day, with most peaking between 3 and 6 P.M.,
says sleep expert and athletic consultant Roger Smith, D.O., of Palo
Alto, California. For example, anaerobic capacity—the bursts of power we
use to sprint short distances or bench press weights—is 8 percent higher
around dinnertime than it is at breakfast. For the competitive-minded, an
improvement of this sort could easily mean the difference between a
personal best and just another sweaty workout.

Not convinced? Smith looked back at 25 years of Monday Night
Football games and found that West Coast teams beat their eastern rivals
63 percent of the time. His interpretation: Since Monday night games
always begin at 9 P.M. Eastern time, East Coast teams are playing well
after their late afternoon prime. But West Coast players—whose body
clocks read 6 P.M. at the opening kickoff—are still at their biological
best.

Of course, you probably don't cross time zones for your weekly
tennis match. But what if it's scheduled for early morning, when strength
and quickness are at their daily lows? One study suggests that regularly
training at the same time of day you'll be competing—whether morning,
noon, or night—may enhance performance.