My Right leg (femur) had broken in 1996. And after some year my left leg bone got cracked on knee. Now its all right. But a metal plate had been placed in my leg to join broken femur bone in 1996, I have not removed it yet and doctor said 'it need not to be removed now, you should have removed that plate before" Now I am not feeling pain on my leg, I do regular exercise, I usually walk for 1 hour, and do exercise like sitting up and down (utthak betthak in hindi) for 50 times in morning, and everyday I increase the count of sitting up and down by 3, is it harmful for my leg to sitting up and down as my one leg was broken and one leg cracked. And plate has not been removed from my leg.