Single-leg glute bridge

Lie on your back with one foot planted and the other leg lifted, then drive through the heel to raise your hips until your body forms a straight line from shoulder to knee. The glutes help guide and direct your skis, and getting them to share the work with the hamstrings takes strain off the knees that the thighs would otherwise carry alone. Working one side at a time stops the stronger leg covering for the weaker. Pause for a second at the top of each rep and lower slowly.