Since I started my cycle I have been having trouble running on the treadmill. At about the 5 minute mark the muscles in the front of my shins get really tight (pumped) and start to burn like crazy. So much so that I can't lift my toes up as I run. At first I thought it was shin-splints because I do have 3 bumps on my right shin, I don't have any bumps on my left shin either and it hurts just as bad but I never had this problem before I started my cycle. I could run 2-3 miles even on the track without any problems at all. I've also gained 16lbs in the last 8 weeks. Could it be that my shins aren't used to the new weight that I've added?
Anyone ever have this problem?

Thanks

Karo