Sunday, January 18, 2015

Dolphin South End Runner's Club 10 miler

Today was my first running road race in quite awhile. First since CIM? Maybe. Time really flies.

Anyway, I did the Dolphin Southend Running Club's 10 miler at Sierra Point, running out and back along the Bay Trail, past Genentech. The run was in the morning fog, reducing visibility to only a few hundred meters. The trail would appear ahead without long-range context. We started at the Marina, but the boats were only visible on the water well within the final kilometer.

The race was a certified 10-mile course. That means if you run the trail, hitting all the tangents, running the minimum distance consistent with remaining on the trail (which was mostly paved, the sole exception being a very short dirt section), you went 10 miles to measurement precision. This was a bit of a fiction, however, since with the out-and-back course, near the turn-around point there were oncoming runners, so basic courtesy required staying to the right of the path. This added a small bit of distance: 2π times the half-width of the trail times the number of full circles of turning. The path was frequently turning as it followed the shoreline, so if it turned for example 10 full circles, which seems a reasonable estimate, and if I had to run half of the time 2 meter from the inside radius, that would be an extra 62 meters run. I recorded 16.2 km on my iPhone, which was 100 meters over 10 miles.

The run went okay for me. I let the first group go, then tried to latch onto a second group, since my rough target was to finish around 10th and this put me close to that position. But that projected placing was optimistic, and I had to let that group go as well when a glance at the phone display showed that I was on the fast side of 4 minutes per km, which is way too fast. My goal was 70 minutes which is 4:21 per km.

After the fast start, I had to slow down a bit to get into something closer to a pace which would get me to the second half intact. This was payback time for the quick start. But that's okay -- as long as the payback wasn't bigger than the original loan. I've got the cyclist's view of the importance of staying in a good group. The drafting advantage, especially in still air like we had here (the water was like glass) in running is small, but still non-negligible. With my 70 minute target time, that's 4.2 seconds for every 0.1% saved in running power over the course of the full race. With running taking place in a full upright position, although speeds are relatively low, wind resistance is still not to be dismissed.

But the draft benefit didn't last long before I had to crack back the pace. I hit the first mile at 6:35 on my timer, which 4:07 per km. This is pretty much the point beyond which I lost the group.

The water stop was at mile 3.4, meaning we hit it again at mile 6.6. Both times I got Gatorade, both times I did my typical 6 step stop, walk 2 steps before the water, grab the water, drink for 4 steps, drop the cup and run again. This seems to serve me fairly well, and is much less hassle than trying to grab and drink in a running stride. The Gatorade was a bit strong for my taste, and there was less in the cup than I'd prefer, but I think the drinks were beneficial even in the cool (mid-50F's) conditions.

At the turn-around the lead man was followed very closely by Molly, the lead woman. She'd end up falling back a bit off his pace, or else he pulled away from her. In either case she ended up second overall. I was close to 20th at the turn-around, which was further back than I'd expected from my observation of the first mile.

There was a junior runner not far ahead of me, and ahead of him a group of two. I focused first on catching the junior, who visibly slowed not too far after the turn-around. Then there were the two ahead of him. I caught one, but the other sped up when I approached him from behind. He veered to run around a puddle in the trail. I went straight through, passing him, and I thought that would be it, but perhaps it was a mistake to look back at him and smile at what had happened. He soon repassed, decisively, and put 20 seconds on my. I thought that might be it, but didn't give up. I ended up hearing someone approaching from behind. I was now worried about both chasing the guy ahead and not being caught from behind.

But then my rabbit slowed. The distance closed quickly. I passed, trying to keep the pace up: it was important to not let my success in passing him reduce my concentration and get caught from behind.

Not too long after, however, I heard footsteps rapidly approaching from behind. I assumed it was the guy who'd been chasing me, but when the runner passed, with considerable speed advantage, it was that guy I'd passed.... twice now. He just didn't give up. But I'd caught him twice, surely I could do it again.

But no luck. Although he couldn't keep up the insane speed he demonstrated repassing me, I wasn't able to close the gap. I crossed the line in 17:27.8, 18th overall out of 79 finishers, 4th in my age group.

Pace analysis is here. I clearly went out too hard. I also finished not far from my starting pace. There's a prominent dip in the pace outbound and inbound where I climbed the only significant hill in the course, once from each side. The outbound leg was 4 seconds faster than the inbound leg, Interestingly Strava has me running at a 4:18 per km average, which is 69:13 for 10 miles, although it notes I have my 2nd best "10 mile effort" at 69:52, which is 4:20 per km. Note Strava won't let me view what my best 10 mile effort is. It allows that for some distances but not for 10 miles. I'll have a suggestion to address this.

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