Will's Hills 22 -- Toughest Workout I've Ever Done

Bike ride there
Warm Up and Hard Mile to Elanor Tinsley Park, 6:18, no HR info
10x100M sprints all out, hills, hard mile back to YWCA, bike ride back home

Recap:
Hard Mile out -- hit this too hard for the beginning of a workout
10x100 -- shouldn't have hit these all-out
12 minutes? of hills -- absolutely died, and ended up walking portions
Hard Mile back -- absolutely exhausted and forgot to start watch, but I'm pretty sure I didn't break 9:30 for this mile

I think I red lined too early and hit the point of no return. I think this is a valuable lesson for beginning, intermediate and advanced runners alike. If you go out too hard, something physically happens to your body and you can't recuperate despite taking rest intervals. That's why some people claim negative splits on marathons lead to PRs and world records. The theory is that the high level of exertion makes your body switch over to burning fat as an alternative to carbohydrates. Since it's less efficient to burn fat, you fatigue faster. But once you start the fat burning cycle, you can't easily switch back to burning carbs for fuel. So you're stuck in this fatigue mode.

To be honest, I don't necessarily believe it. I think it's a theory that hasn't been proven, so I'm unwilling to believe it until there is more empirical evidence. But I can't dispute the feeling of continued fatigue once you red line, even if you do slow down and take it easy. I was just as exhausted after this hour workout as I was when I finished the Houston Marathon.

I'm just glad I didn't have to go to work afterwards.

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This Day Last Year (TDLY) - 6/27/07 - Kenyan Way Progressives, 2.72 Miles, 5x.55M with rest, 7:19 pace, Max HR = 179, Avg HR = 156, Blog Entry.