I'm struggling right now with achilles tendinitis in both feet. I've been doing basically all my runs on the treadmill due to the brutal winter. I read that using the treadmill can actually make you more susceptible to injury due to the possibility of it changing your gait, the repetitive pattern of the exact same foot strike, and the incline of 0 that is like running slightly downhill. Even though the treadmill is a softer material than concrete, do you think doing almost all of my runs on it contributed to my tendinitis?