A Healthy Mix of Rest and Motion

...But new findings suggest that for at least one workout a week it pays to be both tortoise and hare — alternating short bursts of high-intensity exercise with easy-does-it recovery.

Weight watchers, prediabetics and those who simply want to increase their fitness all stand to gain.

This alternating fast-slow technique, called interval training, is hardly new. For decades, serious athletes have used it to improve performance.

But new evidence suggests that a workout with steep peaks and valleys can dramatically improve cardiovascular fitness and raise the body’s potential to burn fat.

Best of all, the benefits become evident in a matter of weeks.
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A 2005 study published in the Journal of Applied Physiology found that after just two weeks of interval training, six of the eight college-age men and women doubled their endurance, or the amount of time they could ride a bicycle at moderate intensity before exhaustion. Eight volunteers in a control group, who did not do any interval training, showed no improvement in endurance.