I have jumpers knee in both of knees so unfortunately when it comes to training my legs it can be tricky. Idealy i want to be proportional when it comes to bodybuilding but with my knees im stuck. Any kind of squatting kills my knees. Right now im able to do leg extensions, reverse hamstring curls ( never get pain on that ) , leg presses are normally good. I have recently read you can increase your leg size by doing intervals on a treadmill. Any advice that could help?