Strengthen and stabilize weak knees with this trainer's go-to lower-body workout

A man performs a lateral lunge outside on grass. His right knee is bent and his left leg is extended, his torso low to the ground. He wears headphones and clasps his hands in front.

A common gripe among people when performing exercises like squats is that it hurts their knees, or that their knees are too weak. Often the issue is not the knee joint itself but the interconnected muscles, ligaments and tendons that enable it to function.

Squats alone won't remedy this, because they typically only target the quads muscles on the front of the thighs and, unless performed with exceptional form, rarely fully activate the hamstrings and glutes.