Jumping jacks in all variations—FITBOOK author Nina Ponath did at least 200 of them every day for 10 days. Here, she shares how it made her heart leap and why she almost gave up. Most of us remember ...

Add Yahoo as a preferred source to see more of our stories on Google. Person doing jumping jacks workout Look, I’m gonna be straight with you – those online calculators that tell you exactly how many ...

Look, I used to think those “100 jumping jacks = 10 calories” calculators were gospel. Then I started paying attention to real people doing real workouts, and wow – was I wrong. Those generic formulas ...

Whether you’re a jumping jack fanatic or you haven’t done a jumping jack since middle school gym class, there’s one thing (okay, two things) most of us can agree on: jumping jacks are fun (they make ...