Originally Posted by
scottfsmith
I watched a bunch of San Milan videos and in one he explicitly said that everyone would benefit from mainly Z2 hours including people doing only 4-5 hours a week total training. My vague memory of his reasoning is if you have a bigger fat-burning engine you will have more of your total power covered by that which will give less you need to make up with the other pathways.
Yeah, he does say that; the idea being to shift the lactate curve to the right and, as you say, increase the proportion of lipolysis at higher intensities. However, that seems a bit speculative to me, since no one is checking lactates in 5 hr/wk riders or doing any controlled studies at all over the > 6 month period they say it takes to see significant improvement in metabolic fitness.
As I may have mentioned above, I’m a 10-14 hr/wk guy and I’m not sure it’s doing me much good. It’ll cost me 95 bucks to go back to the lab and find out.