Want to get more out of your core routine? Train your abs -- fast. The Running Man works your rectus abdominis -- also known as your six-pack muscles -- just as crunches do. "But quickly pumping your arms and legs also builds explosiveness and coordination, which is fundamental to athleticism," says Todd Durkin, C.S.C.S., author of The IMPACT! Body Plan. Ready to try it?
Watch the video below to see how to perform the running man with perfect form.
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