Today I ran my third. and in my current plan, final 20+ miler before the marathon, which is four weeks today - a run of 22.1 miles.
I didn't find the middle miles as thoroughly dull as last time; I don't know if this is down to experience or just the mood I wake up in!
The course was 5 miles round the hilly circuit, then 5 miles up the A6, 5 miles back, round the hilly circuit again, then into the next village and back. On the one hand, the final hilly circuit didn't feel quite as painful as last time, but on the other in the last couple of miles I felt like I'd only got one speed available whereas last time I was able to speed up a touch.
Split timings were approximately like so (going from memory):
First 5 miles: 40:39 (8:08 per mile)
10 miles: 1:22:55, hence 42:16 for the section (8:27 per mile)
15 miles: 2:05:37,42:42 for the section (8:32 per mile)
20 miles: 2:47:55, 42:18 for the section (8:28 per mile)
22.1 miles: 3:05:49, 17:56 for the section (8:32 per mile)
That's pretty consistent; I used to check my watch every mile but that was unhelpful in terms of relaxing mentally - I would spend half the time doing unnecessary calculations and worrying whether I was going too slowly! Today I just looked every 5 miles, apart from at mile 1. I didn't consciously slow down after the first 5 miles; I just went at the speed that felt comfortable, though with an effort to slightly increase the pace in the final 5-mile section. The last couple of miles were physically tough - the tank was just about empty.
I was hoping for 3 hours, but I didn't have the reserves to speed up to make that. I'd guess that's probably because of the half-marathon "race" I ran 6 days ago. Still, according to http://www.runnersworld.ltd.uk/3hr.htm I ought to aim for a training run of 20 miles in 2:55 a week after a raced half marathon of 1:36 at about this stage if I want to beat 3:30 in the marathon itself, and that's pretty much where I am. I'm meant to have about 7 days more of full training, and then gradually wind it down over the last 3 weeks. Not long now!
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