I ran across this quote somewhere on the West Virginia Mountain Trail Runners web site, and Googled Emil Zatopek to try to find the context of the quote.
There is a great advantage in training under unfavorable conditions.
Emil Zatopek was a Czech runner--much along the lines of the later American runner, Steve Prefontaine--who kicked some serious butt at the 1952 Helsinki Olympics.
Zatopek not only won the 5,000 meters, the 10,000 meters, and the marathon, but he did this within a span of only 8 days, and set Olympic records in all three events!
Zatopke was a road runner, not a trail runner, but his passion for perfection ceratinly has parallels in Ultrarunning:
"When a person trains once, nothing happens. When a person forces himself to do a thing a hundred or a thousand times, then he certainly has developed in more ways than physical. Is it raining? That doesn't matter. Am I tired? That doesn't matter, either. Then willpower will be no problem."
We forget our bodies to the benefit of mechanical leisure. We act continuously with our brain, but we no longer use our bodies, our limbs....We have a magnificent motor at our disposal, but we no longer know how to use it."
I found more, much more. We would all do well to emulate Emil Zatopek.