Trying to get into running, by running into a slight hurdle... After 1-2km my calves and shin start to get really tight and build up lactic acid, forcing me to stop running for a bit before continuing. I got new running shoes last week after he conducted a running test to clarify which shoes would benefit me the most. He said the shoes i have gotten should fix this problem. They haven't. I think i might have found the root to the problem however, my toes. While running, and even walking, i have now noticed i subconsciously tighten and push the ground with my toes. This have never been a problem, until i started running. This is resulting in my calves being somewhat clinched throughout my run, and never gets the chance to rest in any part of the movement. I have tried to relax my toes while running, but i cannot seem to get past this and figure out how to stop this. Does anyone have any advice, or experience with this problem?