Appreciate the thoughts. Maybe we're talking about degrees (both temperature and effort). Training at 6000 feet or 70 degrees, and backing off a little bit to accommodate for heart rate/effort is one thing. Training at 9000 feet or 80 degrees (with 90% humidity - typical July morning), may require too much backing off.
Also, the elevation is a joy compared to the heat. At 9000 feet, for a long run, I back off to perceived effort level, find whatever the sweet spot for a long run should be (let's say 160 HR), and head off indefinitely at whatever pace that dictates. Running the same goal, roughly at 95 degree real feel, I'll find roughly the same sweet spot for pace and HR. Everything seems about the same, except the elevation run will keep going for 10+ miles, but the heat run will be over after 6 miles because of water loss and exposure. I'm probably "blessed" with being an efficient sweat-producer too
I suspect that even fantastic runners like yourself, Pilot, or K-Bo even begin to fall off the curve for performance predictability right at the edge of typical Houston mornings. That is, right around 90F real feel, God determines whether you crater, excel, or somewhere in between.
Anyway, there were so many stinking days like that around here; I had to use indoor speed work in the summer so I could run faster in the fall.
94chem,
That, sir, was the greatest post in the history of TexAgs. I salute you. -- Dough