Despite not being a newbie i've been hit with calf pain on one(!) leg (right) again. Haven't had that in a while. Since I never really thought about the motion of the leg and a potential cause for the pain in a calf, here are a couple thoughts - maybe some of you have better ideas. Calf pain came 48 hours after a 10k asphalt BF training run. Speed was not too slow, at approx. 5 min/km. The aftermath: The 10k asphalt was on a (closed for vehicle traffic but heavy trafficed by bikers, skaters and runners) and since we drive on the right here I stayed on the right side of the road on both halfs of the run (I just turned around after 5k). In order to keep water from staying on roads they are a little bit "falling" to the right and left surface wise. When running on the right hand side of the road, the right leg always had to do a little more work in order to keep me up (the left just bent more?). That would be an explanation. The left leg is fine, no calf pain there. So a trick in order to avoid that would likely be to either stay in the middle (if possible) or alternate between sides if possible. Any other ideas why it would just be one leg ? I did not have any calf pain on a 14k competition at same speed the week before, that was no asphalt though. I do have an upcoming 10 competition on Saturday, hope that calf gets quiet by then. Couldn't run today and walking a stairway down triggers that calf pain pretty effective (as does bending the knee forward and holding the body weight).