What should i do if i have chondromalacia patella pain?

Gentle exercises : Chondromalacia is a softening of the cartilage between the patella (knee cap) and underlying joint. The best early treatment is to gently strengthen the quads (thigh muscle). Step up with your painful leg onto a 4" block/book and down. Repeat as many reps as comfortable and work up to doing 200/session. Then do it on a stair, which is typically 6". This is to avoid too much knee bend/strain.

Therapy: Chondromalacia patella (runners knee) is due to overload of the patellofemoral joint (knee cap against the end of the thigh bone). Running caused high forces in this portion of the joint. So does arising from a chair, going up/down stairs. Treatment consists of activity modification, ice, anti-inflammatory meds and therapy aimed at flexibility and strengthening, especially of your core.