To find out, I went to Dorney Lake and did the VOTWO event. It was two laps around “return” lake rather than the main lake. At the start, they apologised for having to change the course, apparently something somewhere was flooded. They did promise that it was still an accurately measured course.
It was quite cold, a bit sunny and most of first 2.5k with running with a strong tail wind. The next 2k or so has a strong headwind, and had a slight up hill in places. The last bit had a side wind.
For each 1k segment, my times were:
1k: 3:41, HR=168bpm (last 2 mins)
2k: 3:49, HR=169bpm
3k: 3:53, HR=171bpm
4k: 4:20, HR=174bpm
5k: 4:09, HR=173bpm
6k: 4:04, HR=170bpm (23s slower than first lap, HR shows I eased off a bit)
7k: 3:55, HR=172bpm (6s slower than first lap)
8k: 3:57, HR=173bpm (4s slower than first lap)
9k: 4:12, HR=175bpm (8s quicker than first lap)
10k: 3:59, HR=175bpm (10s quicker than first lap)
I thought that my pacing was quite good. The first 100m involved dancing around some of the slower runners, including running on the grass a bit. The rest of the first 1k did feel a bit easy. I knew I was going quicker than the 4:06 per k I was aiming for but I knew I had the wind with me. Looking at my times/HR, I did ease off a bit at the start of the second lap.
Another thing about pacing is to see how I compared to others. Ignoring the 1st k, two people overtook me at around 2.5k, and one person overtook me at 8k. Two other people tried to overtake me at 8k but they didn’t manage it and fell back quite quickly. I did catch one person at about 8.5k and I made that stick quite easily. So that again suggests that my pacing was quite good.
Actual time was 40:01. Oh, for those two seconds. In terms of VDot, it’s just about 52.
Update 3 Feb 2013: Official results are now out. I did 40:06 per the chip. But I started back from the front and the chip was one of those finger dab-ing ones that was after the finish line. Ignoring the lady who smashed the world record for 10k (or just did one lap), I came 12th out of 211 people. I was also first vet. If I had known that, I would have stayed and got my prize.