Trail Running 141

Kevin, who is a new grad student under Dr. Kolar, has been going out to Lake Thunderbird and running trails recently. This is something he likes to do, and he used to do in South Carolina. So, we arranged to go out and hit the trails yesterday afternoon. It was a perfect day for running. It was sunny, in the 50's, breezy (but you didn't notice in the woods), and there weren't many people out there.

The run started out pretty well, with 9.5-minute miles. However, we quickly left the easy trails and hit the expert-rated gold trail, which consists of about 10 miles of nasty terrain, which I can't imagine anyone actually riding a mountain bike on. The pace stayed pretty solid for the first hour. And, by solid, I mean sub 10-minute miles, on average. The second hour of the run was slightly slower, both due to fatigue and due to the nature of the trails, which involved a lot of ridiculously steep down and up small ravine cross, tight, slalom switchbacks, etc. It really slows you down when you constantly have to be redirecting your energy, braking, etc., as well as propelling yourself forward.

Aside: After I got back, I looked on-line to see if there was a general adjustment for calculating calories burned doing trail running vs. road running. Much to my shock and horror, many of the posts on message boards were saying that you burn less per mile on trails because you don't run as fast. And, even though you go up and down more, the downs balance out the ups. Some people were on the right track. Then, I saw an article that suggested 10% more for trail running. I think that's not unreasonable for running on regular trails, which decrease your efficiency because of the surface, less straight, level terrain, etc. I don't think the expert trails at Thunderbird come with a 10% escalator. I think it's significantly higher. I'd love to get the thoughts of others ... maybe I'll have to take people out there when they come to visit.

Things were still going okay when we finished the gold loop. We were nearing the 2 hour mark and had finished more than 11 miles. Kevin had run through a side cramp. My right ankle was starting to get sore, but that was my main issue. So, we charged on. We started part of the blue loop, which I quickly admitted was a mistake. Things went downhill quick, at least for me, after the 2 hour mark. The issues were two-fold. First, my ankle was hurting more and more. Second, we hit some nasty, muddy terrain that I didn't want to run through in my running shoes, I had to tread lightly.

After finishing the horn of the blue loop, we decided to bail. We were somewhere around 13.5 miles into the run at that point, and we were nearing the 2.5 hour mark. Fortunately, it was mostly downhill from where we were, so I gritted out 3 minutes or so running at my normal road running pace, then I just had to hobble up one final hill to the parking lot. I arrived at the car and stopped my watch right at the 2.5 hour mark.



My watch registered 13.29 miles for the run. However, this was not the actual mileage. Kevin has the same watch as me, and he consistently was closer to the trail mile markers than I was, although he was a little on the low side, too. We think his watch is set to record more often than mine, so it does a better job of being accurate on all the sharp turns and switchbacks. After 10 miles, his watch was just over a quarter mile off, whereas mine was more than a half mile off. We lost the mile markers somewhere after 10, but we used the correction from the first 10 miles to estimate the total run distance: 14.1 miles.

My watch gives 2,219 calories for 13.29 mi. Correcting for the mileage, I'm over 2,350 calories. However, I'm horrified by the per mile calorie burn rate of 167, which is less than I register doing the road running. I don't think it's even close! Plus, my watch registered almost 2600 feet of ascent and descent, which I'm guessing is low, too. I need to ask Kevin what his registered. I'm guessing mine is low for the same reason as the mileage is low, that it wasn't registering enough to track all the quick downs and ups, which were plentiful!

My ankle is sore today. Otherwise, I feel pretty good. I took the dogs for a walk this morning (almost 2 miles) and Jenn and I redid their kennel enclosure to limit their potential digging. I'll need to hit the elliptical tonight, after dinner at mom's, in order to hit my 500 calories today.