I wonder if anyone has heard of this idea. Basically as you work on speed your endurance suffers a loss and if you do a lot of endurance work your speed suffers.
So my question is what effect does endurance work have on the cns? I see in the vertical intergration Charlie uses low intensity work has little or no effect on the cns which would lead me to believe that there would still be reserves to work on speed. But from a practical side I do not normally have the reserves to work on speed during high volume cycling training.