Forget the floor—this high-efficiency standing workout uses light resistance to target your upper abs, lower abs, and obliques in a fraction of the usual time.

I don't think I'm alone in saying sit-ups aren't fun. I don't know if it's because I need to have someone or something there to make sure my feet stay put on the ground during the full movement or ...

Beth Skwarecki is Lifehacker’s Senior Health Editor, and holds certifications as a personal trainer and weightlifting coach. She has been writing about health for over 10 years. Sprint interval ...

Workouts I’m a personal trainer who works with seniors: These are the 4 core exercises I wish everyone would do before they turn 60 Fitness ‘I’m a Pilates teacher and these are the 5 core exercises I ...