Sliding Reverse Lunges

I.Love.These.  Use a towel on a wood or tile floor. Use a paper plate on carpet. Or a fancy disc, if you have one. This exercise is awesome because it is easier on the knees than regular lunges. By keeping the back leg straight, it stays solid and the knee stays safe. Your front leg should be doing most of the work.  The hip flexor of your back leg will get a nice stretch too! Stay on the same leg for 10-20 reps, then switch to the other side. Hold on to something to start and eventually you may add weights.