Whenever I jog these days, which I do regularly, I'm always right on the verge of pulling a hamstring. I've had several bad pulls in the past, usually resulting from sudden activity without warm-ups or stretching. (I don't do that anymore.) I haven't pulled a hamstring in a long time, but for about a month now the back of both of my thighs tighten up like springs whenever I run, and I'm sure that one wrong step will have me limping for home. Question: What KIND of a doctor should I see about this? Orthopedist? Rheumatologist? Neurologist? Other? Also, what might cause a condition like this? I always warm-up and stretch before exercising, and I eat very healthfully and stay well-hydrated. Does this sound like a vitamin deficiency? Background: I'm 51 and work out 3x/week, lifting weights and jogging. I often do intervals in place of jogging, but instead of exploding into my sprints, I ramp up gradually to reduce the chances of another strained hammy.