I was diagnosed with chondromalacia in my left leg 4 years back. Doctor advised to take precautions like not to jump, run, jogg, fold knees, climb stairs, told me to do exercise and gave some medications. Sometimes I didn't followed the precautions he told me. Now, whenever I give stress on my knees, it pains for few days and if I take rest, it gets back to normal. Now, I have joined karate classes, where I have to jump, run, hop etc, so it pains. Kindly recommend some solution.