Ever feel like you're giving it your all at the gym, sticking to your routine religiously, but there's that one muscle... yes ...

In other words, that sharp exhale helps you brace your core and generate more power—without the drawbacks of breath-holding.

Glute corrective exercises—such as couch stretch, frog stretch, which Brockman demos in the video—help with hip mobility. And "better hip mobility equals better glute gains," she says. Why? Tight hip ...