Posted: 01/03/2015 at 23:12
Golfer - yes it's a balancing act. Good run at similar speed to a few others,
You can't do all your long runs very slowly or you won't prepare for the race effort but the 20 at 7s should just about be ok if running with the pacer makes it a lot easier than running by yourself.
a flat out 20 (faster than marathon pace) potentially might take three weeks for you to recover from and the benefit from a great 20 could be lost as you could have three rubbish weeks training afterwards as you struggle to recover.
I think you get an idea if it was too fast in the 3-4 days afterwards and if you still feel tired and have a rubbish session on Wednesday, it was too fast!
I used to do 20 mile races but have decided against it recently as it potentially takes too much out of you. My best recent marathon came the year my planned 20 mile race got cancelled but psychologically I previously felt a 20 mile race at marathon pace helped me but I wasn't convinced I ran as well in the marathon 4-6 weeks later past 18 miles as I did during the 20 si it might have taken more out than put in.