Your knee is just a joint, and it needs all of the surrounding muscles for it to work properly (and not hurt), Summers explains. "The muscles around any joint can either cause or inhibit pain, and having strong glutes and a proper quad-to-hamstring ratio will help to keep the knee happy and healthy," she says. Strong, functioning glutes also keep everything in proper alignment, because they work with your hips to keep everything in neutral rotation, Burmaster says. Weaker glutes, on the other hand, could cause your knee to accidentally rotate when you walk, in a way that could easily cause torn ligaments, she says. "Knee injuries are the absolute worst to recover from, and having strong glutes is an easy way to prevent them."