Sir, I was very fat boy I lost 30 kg weight by skipping and running on hard surface, that's why My both knees have been paining now badly for 8 months ,I can't stand for 5 minutes continuously ,I can't run ,can't walk fast, I took medicines, calcium ,tablets, vitamin D tablet, There is not any injury found in X-ray. I am very sad for this problem. How do I get rid of this problem please plz suggest Thank you.