Running doesn't get old, but we do! Maintain your stride length and pick up speed by incorporating more leg workouts, namely calf exercises, into your routine
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Aging comes with some unpleasant updates to the body (there should be an actual panic button for finding your first gray hair). One of the hardest on your ego? Not hitting that same PR you set in your 30s despite still being an avid runner. In fact, a new study in Medicine and Science In Sports and Exercise found, not surprisingly, that runners significantly slowed down with age. But the finishing times had nothing to do with how fit the older folks were; the older runners actually took the same number of strides as their younger counter parts (about 165 per minute). What changed-and caused their slower time-was the length of their step.

The study authors aren't definitively sure why our stride length shortens as we age, but all of the correlations between speed, stride, and muscle mass pointed them to the muscle strength of the calves specifically. In the experimental group of runners, stride length-and therefore running speed-decreased by about 20 percent between the ages of 20 and 59, while ankle power dropped by about 48 percent in that same time frame. (Learn How to Overcome Age Obsession.)

And, even though the solution to longer steps may seem obvious, researchers say your best bet to increasing your speed is actually to hit the lower body exercises more: The stronger your calves and ankles, the longer your stride will naturally become and the faster you will run. (Try these Two Powerful Calf Exercises.)

"If we can maintain calf muscle strength as we age, perhaps we better maintain our stride length and velocity," says Paul DeVita, Ph.D., an author on the study and director of the biomechanics lab at East Carolina University. And while more research needs to be done to confirm this, DeVita's team didn't see this same correlation with hip or knee strength, indicating that that the calves really are key.