Tight hip flexors, especially a deep muscle called the psoas, can silently stress your spine. Here's why this muscle deserves more attention—and how to strengthen it. Lower back pain is often blamed ...

You’ve probably seen it all over your feeds: Fitness pros and physical therapists talking about “training the deep core.” But unlike crunches or Russian twists, these exercises don’t come with a pump ...

“Back day” has become a staple of fitness social media, often framed through aesthetics alone.

If you can get past its misleading and off-putting name, the ‘stomach vacuum’ exercise can be a welcome addition to your training routine for its ability to target the deep muscles in the core. Unlike ...

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 ...