Whether you're switching up your typical strength training routine or rehabbing after injury, introducing instability into your workouts will have you shaking and aching like never before. There are a ...

The Bosu ball, whose name stands for "Both Sides Up," is a unique training tool that lets you work on both stability and instability. Its clever design forces you to engage muscles you might not even ...

Nikki Metzger is Women's Health's Next Fitness Star winner and the creator of the heart-pumping, cal-torching fitness method you'll find in her Ignite routine. I'm obsessed with training with the BOSU ...