But, let's be honest, how much attention do you give to the back part? That small yet mighty section known as the posterior deltoid. If your answer is "not much" or "almost none," don't worry, it's a ...

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. It’s easy to almost ...

Leoni Jesner is a fitness, health, and lifestyle writer who has contributed to Byrdie and LIVESTRONG.com, among other publications. She is also a personal trainer, mat Pilates instructor, and ...