The hamstrings and glutes play an unsung role in protecting your knees. That was the major lesson I took away from my physiotherapist after tearing both anterior cruciate ligaments on the soccer field—in separate incidents in my late 20s and early 30s. Running down the back of the thighs, from the hips to the knees, the hamstrings help to stabilize the back of the knee joint to prevent hyperextension. Article continues below You may like At the same time, they work as shock absorbers to protect the ligaments and cartilage, and they also help you decelerate at high speed. Meanwhile, the glutes, which form a major part of the posterior chain system connected along the back of your body, help to stabilize the pelvis and keep your hips aligned to stop your knee caving inward under strain. I’ve tried countless ways to strengthen these two muscle groups over the years, but there is one exercise that has stuck with me: gym ball hamstring curls. Now, whenever I have a few minutes spare at the end …