Rizzi
April 23, 2026, 3:43pm
1980
I wish all readers here would expand and read these 2 posts from Coggan himself:
Whose “zone 2”?
Sorry, but you seem to be laboring under the common misconception that “zones” are discreet, and everyone agrees on them.
The reality is that they are defined.by rather arbitrary, disputable cut points, because all physiological responses (and resultant adaptations) reside on a continuum, such that any such divisions are largely a mental convenience.
TL,DR: Fatmax, LT1, LT2, etc., are really all just different measures of the same thing.
I don’t think that the literature allows you to draw that conclusion. In fact, quite the opposite, i.e., the largest increases in mitochondrial respiratory capacity have been found in studies with the most intense training programs.
Because (seriously!) there is no such thing as “zone 2” (or zone 4, etc.). Such distinctions, while sometimes useful, are almost completely arbitrary. In point of fact, exercise responses and adaptations reside on a continuum, and you have to go well up the intens…
Maybe ISM has nice new cellular measures now but the point he makes was known training principle long ago…just pick the right source. I get a feeling why Coggan was frustrated…