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.

The amount of calories you burn doing jumping jacks can vary based on how long or how fast do you them, as well as on personal factors that affect your metabolism. Jumping jacks might seem like a ...

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 ...