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 ...
Add Yahoo as a preferred source to see more of our stories on Google. Jumping jacks, a staple of school gym classes, are not just for kids—they can also reveal much about your health. Even if you ...