I recently increased my number of workouts per week and I am experiencing pain. I am 25 years old, and I'm in good shape. For the last 2-3 years I have been running on average 1-2 times a week. Last summer I increased this to 2-3 times a week, without experiencing any discomfort or sideeffects. This March however, I decided to step it up, and started running/working out 5 times a week. I run about 3 miles on treadmill each session. For the first month or so, everything was fine. I then started to feel pain in my legs. I figured this was just my body adjusting to the increased amount of pressure I put on it, so I kept going. A couple of weeks later a started feeling pain on the backside of my left knee. I figured the same thing, that it was probably my body adjusting, and kept going. A couple of weeks or so later it got worse, and I started limping down stairs. I kept running another week, to see if it got better, but it didn't. During this last week the first part of the run I would limp a little until my leg got warm, and then I would run normally. After the workout things would feel better, but then it would get worse the day after. Any idea what this could be?
I've cut down on the running and started doing other cardio exercises instead which has helped.
Any input would be greatly appreciated.