Originally Posted by
DrWJODonnell
here is a basic explanation for why to ride low intensity. as long as you are in the aerobic realm, you skew your body to believe it is resting when it is not. That is to say, if you're doing 150 watts of work at 120 BPM HR, your body will adapt quickly and you will be able to do the same workload at less, say 110 or 105BPM. In this way, you essentially raise the ceiling of where aerobic becomes anaerobic. Why is this important? Lactate threshold is VERY important.
After watching this type of discussion on several boards/posts, at least here is a reason. And it makes sense (not that I'm a Dr. or anything). But it doesn't answer the question completely (or maybe I'm dense--a distinct possibility).
But if a person's body adapts to 150w at 120bpm, won't it do the same at 200w at 140bpm? or 300w at 160bpm? What makes the lower intensity stuff magical? And because these workloads are higher, won't the adjustment be even higher than lower intensity stuff? (And of course, a person has to do recovery rides for this adjustment to occur.)