Originally Posted by
tadawdy
Not so much the stress of running itself, as having flawed running mechanics. Landing on the heel rather than the fore/midfoot, either because of overstriding or inexperience (we walk with a heel strike, and beginners often see running as fast walking) leads to a higher rate of force development and higher peak forces. Not to mention giving you a nice eccentric contraction of the tibialis anterior with each stride.
For me it was getting back into running after a long time of no running. My heel strike is not a problem, it was just the return.