All I know is now I am afraid to go out and run for fear of tearing or snapping the Achilles tendon or doing some type of other damage. I do warm up
for 5 or more minutes before I run and cool down
for about the same. I do stretch, although maybe not as much as I should. I really want to be a runner, though, and have been dreaming of becoming one for many years. I do have new, much better shoes now. I'm thinking of maybe just taking this week off and seeing if it gets better.