Talking weights...

When to lunge and when not to lunge? This presents an interesting question. To answer, it depends. It depends on possible injuries your recovering from, ACL (anterior cruciate ligament) or PCL (posterior cruciate ligament). These two ligaments form an X inside your knee and there job is to keep the lower leg bone in position with the upper leg bone.

A study published in Medicine & Science in Sports & Exercise reported that the lunge placed little stress on the ACL but highly stressed the PCL. So to answer the question, go lunge crazy on leg day if your recovering from an ACL injury but stay away if it's a PCL injury or at least until the doctor gives you the okay.