Peeps! it's been way too quiet in here so I will try to spur some serious or not so serious debate about the mythical 20 mile training run. Lots of training programs have peak miles ending at 20 or 22 miles with the argument that you are supposed to run them slow so that the your approximate race time and 20 mile time would be close enough for you to cruise past the dreaded wall. I just ran my first ever 20 mile training run. I've run 6 marathons when I was in my 30's, but I peaked out at 18 or so for long training runs. I even PR'd at 3:24 with my long run at 17 miles. So...I've read the literature about glycogen reserves and the 20 mile mark, I've also read about the psychological effect of running for 3+ hours and that the only way to prepare for that feeling is to run 3+ hours. Does anyone feel that the 20 mile mark is more physiological in that your bodies becomes better at storing glycogen and metabolizing fat or are you like me and feel that the power of the mind can propel you further than science can explain? My Sunday run was horrible...I hit the wall at mile 2 with flat legs, breathing hard despite the slow pace and it just got worse and worse after that. At mile 6 of an out and back 12 mile course I was just going to call it quits at mile 12. Even my arms felt tired and sore. The week's speed work out and higher than normal mileage had left me with nothing but that soggy white stick after the tootsie pop. Much like the Grinch I had a wonderfully horrible Idea. If I could run 20 miles feeling like this I could easily run 26 when I was rested and had fresh legs. Armed with stupidity (momma says stupid is as stupid does) at mile 12 I turned around and headed back out. The last 4 miles were at a fast jog. When I saw my truck...at last...I knew that I had done something significant. I know that I can run 26.2! the BQ that I am shooting for remains to be seen, but ....I have that edge now. I know!!! So which is the more important aspect knowing that you can do it or having the ability to do it? And don’t be a wuss and say both you can't be like the Swiss and remain neutral!!! Karl

My Sunday run was horrible...I hit the wall at mile 2 with flat legs, breathing hard despite the slow pace and it just got worse and worse after that.

Not sure what you felt at mile 2 but I'm fairly certain it wasn't "the wall". I think 20 is a good distance that someone arrived at because it gets you out on the road for nearly as long as marathon distance but at a slower pace. Nothing magical in 20 except that it won't beat your body up as long as longer distances unless you run it at race pace. Long runs at easy pace will help your body burn more fat and less glycogen helping your body conserve the glycogen it has further into your run on race day. Once you run out of that glycogen, you hit he wall. I don't think long faster efforts have the same training effect. You ran a great race time with nothing over 17 miles. Physiologically 17 was plenty for you then. Mentally can obviously be a different story. I ran my first marathon at 41 years old on a long run of 14 and I never hit the wall. I wouldn't recommend it though.

Nothing magical in 20 except that it won't beat your body up as long as longer distances unless you run it at race pace.

This made me think of something Jeff and Jscovill said to me the night before my first marathon... "something magical will happen at 7"... clearly I have nothing to add, but that made me giggle...