More Hadd Context

Here's the best write-up I've seen this morning providing context for my current training thinking:
Interpreting Lactate Curves for Ironman Athletes by Alan Couzens

I bring to that write-up the thought that I have a low proportion of type I and high proportion of type IIa muscle fibers when compared to the mythical ideal endurance sports physique, or even to the front third of the actual pack.

I could do a lot of zone 1 (under Aerobic Threshold) training to work on maximally training type I fibers. First, when one considers the examples of elites who've clearly come close to maximizing the potential of their type I fibers, one gets context for "a lot" such as Mr. Couzens' line, "That inch and a bit difference of the graph, represents a difference of ~7000 hours of steady state aerobic training in the real world!" Second, even if my type I muscle fibers were maximally trained and I carried little extra body fat they'd still be required to drive a relatively high mass (skeletal frame and other types of muscle fibers).

Couzens writes: "A secondary objective for the sub-elite Ironman, and perhaps a primary objective for the elite Ironman is to improve the oxidative capacity of the athlete’s type II fibers."

For me, definitely a sub-elite Ironman, I think that's my primary objective, and almost certainly my best return on resources required. That applies not just to Ironman but to all of my endurance sports activities.