Years ago during a training trip out west in the Grand Tetons, our cross country team ran from Jenny Lake at 6000 feet up to Lake Solitude at 9000 feet and back down again. We did that run without water, and it was strongly advised not to bend down and drink from a stream or lake due to the presence of giardia, the microorganism that infects waterways throughout the West.

So the first nine miles were not so bad. But coming down another nine miles without a drop to drink turned into a cringefest. I was getting dehydrated in the dry mountain air. Plus the angle of the trail was steep in many places. My thighs began to ache and it was hard to put on the brakes with every step. In youthful courage I let the feet fly at some points. Finally after a solid hour of downhill running I arrived back at camp sore and thirsty.

You’d never think running downhill could hurt worst than running uphill, but it did that day.

Recently on our anniversary weekend out in Galena, Illinois, I had another downhill running experience that added up to pain. We’d cycled 50+ miles in the Ups and Downs Ride sponsored by the G.O.A.T.S club in Jo Daviess County, and it was fun.

But I was a little stiff the next morning after all that climbing in relatively cool weather. We got up to run on Sunday morning in more cool weather and started east from our hotel toward the riding stables at the bottom of a valley in the Eagle Ridge Resort complex.

We went down and down and down. At one point the degree of incline reached probably 12% for a short stretch. That’s when I felt a sharp twinge at the back of my left knee. It kept up the rest of the run. That’s never good. For days now after the trip the back of my knee has been sore enough that I have not chosen to run at all.

There’s a good reason why it might be hurting. There’s no ACL in that knee, and last year I had meniscus surgery to remove a bit of torn material on the inside front of the kneecap. But this was a new type of injury than I’d previously experienced.

I’m supposing the reason for what happened is simple: Without the forward/backward support of an ACL to stablize my knee, the back of my leg experienced a hyperextension due to the extra motion created by downhill running.

The fact that it still hurts is a bit worrying. It feels most like muscle soreness with some compensatory ligament strain. So it may take time to heal.

I’ve also biked twice with the knee since last weekend and am not certain whether that is a contributing factor to the soreness or not. Doing all that pulling with the hamstring during some long and steep climbs last weekend may well have caused a strain of the muscle at the back of the knee. Many cyclists do get knee injuries from overuse.

So I’ll have to wait and see a few more days how this scenario plays out. The ironic aspect of this injury is that we were running quite slow going downhill that morning. Yet that may be the actual cause of the injury. Rather than floating down the hill as I once might have done, every step was a brake action of sorts. Getting older is a tautology of sorts when it comes to pace. If you go fast it hurts, but if you go slow it can hurt even more.

Who knew running down hill could hurt so much? It’s just another tarsnake in the experience of this humbled triathlete.