After the San Francisco 50-Miler, my tendon wasn't so happy. Well, it was actually OK later that day. And the next day, when I went for a bike ride. But Monday morning, when I put running shoes on? Nuh-uh.
So I think I've figured out that the real problem isn't so much the lower heel-toe drop, but merely the shape of the shoe. When I walk around barefoot, usually there's no pain at all. And if barefoot were a shoe, that would be a zero-drop shoe, which should hurt even more if that were the cause. What I've noticed is that the biggest cause of pain is when something puts pressure on the back of my heel, something like, say, a running shoe.
Those new shoes that started this whole mess, not only are they not broken-in, but they have an unusually aggressive heel cup. Yep, that was probably it. So as much as I want to like the shoe, and how I like everything else about it; the low weight, the natural motion, the adequate cushion, the traction, the speed, I'm probably going to have to send them back. And with a rapidly-dwindling number of good miles left on my current trail racers, I'm going to have to find a new pair of good trail racers, and soon.
Speaking of which, if you can recommend a good pair of trail racers, I'd love to hear it! Leave a suggestion in comments. If you want to know more about what I'm looking for, look here.
Tuesday I ran in my road shoes, which have a 4 mm heel-toe drop. My tendon complained a little throughout, making me fairly slow for a flat, paved training run. I need to get used to that surface and those shoes again though, considering I have a paved race coming up.
Wednesday and Thursday, I did mostly-normal training runs. What I noticed was that my tendon hurts pretty bad for the first mile or so, but the pain goes away almost entirely after that. So until the "injury" is gone for good, I'm going to intentionally start slow in all my races.
In the meantime, I'm trying to do a good amount of strengthening exercises to get my tendon back up to par. Apparently, tendons don't stretch. At all. Or at least, they're not supposed to. So doing a stretch where you're really targeting a tendon area is a bad idea. Just stretch the muscles involved, and do low-impact strengthening exercises in between.
Now at the end of the week, my tendon's feeling stronger every day, to the point that I had no pain at all today. Bodes well for the race tomorrow.