Speedwork and Distance Running

Perhaps the biggest fallacy in distance training is that you have to do lots of speedwork to be successful.There is no denying you need to do work at the appropriate time that is harder and faster, but,the benefits of grinding out multiple reps and sets of 200's--400's--800's etc. are grossly overrrated.I recall in high school that it was a rite of passage to do all out 200 and 400 meter reps in track practice.Now,I am not saying that some runners will not do well if they go heavy on the intervals,I'm simply stating that they are not a necessity to achieve distance running success.
Joe Henderson,who know running as well as most anyone says this:
"At the risk of sounding like a heretic,I'll state right off that speed is the most overrated commodity in distance running.Speed doesn't come in appreciable amounts,no matter how many dashes a young runner puts in.Speed is there,inborn.Some have it,some don't. Training can only alter the maximum level by a few scanty tenths of a second,yet hours of effort are poured into the search for it.The paradox is obvious:the average four minute miler(or even five minute miler) does 10 times as much speed training as a 9:1 sprinter.Speed,the speed needed to race adequately at distances longer than a mile,anyway,is quickly sharpened down to the limits of our ingrained abilities.After reaching that point,additional speed training is of dubious value.And worse,it hurts.It hurries the inevitable rush of fatigue producing lactic acid through the muscles.And,it raises the risk of stress injuries."
Don't buy into the, 'if the training doesn't hurt, you're not going to get better' fallacy.