Haha - and I will give you the exact opposite advice (as I like to do):
Train well for downhill running - get plenty of long, sustained downhill training runs in. Do not let the
crowd hold you back and try to bank as much as you can for as long as you can, as long as you keep your
heart rate under control. As long as you can avoid the crowds (which is a huge challenge), it can be
one of the easiest courses around if the weather is cooperative.
I'm just going by what I've seen lots of my club members do, none of who are ultrarunners. Every single one of them that does the first 5k too fast, crash and burn in the end. Many of them are almost running a 5k-5mile race pace in the beginning. Best to either go by your HR plan or you pace plan. Both equating to a slower first half marathon with a faster half, or even splits (give or take a minute).
Take it or leave it always, of course. If anyone wants to run the first 10k of Boston at 10k pace, by all means go for it.
Max McMaffelow Esq.
Aerobigal! (thx Jimmy!)
Shiksa..Congrats on maf graduation..you deserve at least a PHD in Maf with all the effort you've shown. Your half should be an awesome experience.
Just running for the fun of it!
Pace isn't important if you use a HR monitor and follow a HR plan. I can see that. But if you don't use one in races, then it is very important. It is important not only to know a proper pace, but then to make a pace plan that doesn't sabotage the race. Usually the only way to do that is to go out too fast. Even with a HR plan, if you planned to keep at 65% for the first 6 miles, and you run 70%, you can't get it back at the end.
Here's a quick study of last years Boston winner Robert K Cheruiyot, The pace in the parenthesis is for each 5k). Notice how he started at a pace 8 seconds slower than his ultimate race pace of 5:07. His first half was run 15 seconds slower per mile than his second half.
Cheruiyot, Robert K
5k (5:15)....10K(5:14)...15k (5:11)...20K(5:24) Half
0:16:20.......0:32:34.....0:48:40.......1:05:27 1:08:45 1:21:02 1:37:11 1:52:39 2:07:25
half marathon time: 1:08:45 pace: 5:15
2nd half: 1:05:28 pace: 5:00
Most of the guys that I see in the top twenty, save a few, ran slower in the first half, and took it easy that first 5k.