Jumping jacks give a quick cardio boost and improve stamina, but they do put sudden strain on the knees and ankles,” added Dr ...

"Hearst Magazines and Yahoo may earn commission or revenue on some items through these links." YOU MIGHT THINK back to your childhood gym class and remember learning the basics of physical fitness, ...

The jumping jack is an effective way to stimulate all the vital muscles of your body. It is a full-body exercise used in cardio and warm-up sessions. Jumping jacks include resistance and aerobic ...

Look, I’m gonna be straight with you – those online calculators that tell you exactly how many jumping jacks you need to burn 500 calories? They’re basically making educated guesses about your body.

Real talk: The thought of doing jumping jacks may be only slightly more enticing than burpees. It may bring back memories of pre-dodgeball warm-ups back when dodgeball was part of gym class. Yet, ...

FITBOOK author Nina Ponath loves challenges—this time: 10 days of jumping jacks. Photo: Getty Images / Antonio_Diaz; Collage: FITBOOK Jumping jacks in all variations–FITBOOK author Nina Ponath did at ...