Your core (that means both your back and abdominal muscles) is your source of power—seriously. It's also what helps stabilize your entire body, prevent low back pain, and impact your posture, helping ...

Looking for a quick ab workout to fire up your core? This seven-minute intense ab challenge targets your lower abs with no equipment. To find out for myself, I unrolled my yoga mat and gave it a go ...

Add Yahoo as a preferred source to see more of our stories on Google. "Hearst Magazines and Yahoo may earn commission or revenue on some items through these links." I love working out, and a good ...