Stretching before a run has always been a little iffy in our playbook. It’s hard to lengthen muscle fibers before they’re warm and trying to do so can lead to injury. But warming up is still a good thing, so try an active warm-up. A dynamic warm-up raises your heart rate a bit while

priming your joints for action. We created this video of five moves to do before you hit the ground running. Check it out! And be sure to enter to win running shoes for a year from Asics to help jump-start your January.

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Running 101: The Active Warmup