You may be right, but I’m not convinced that total stress on your body is what you want to measure. I don’t know this, but I find it hard to believe that the stress on your rowing related cardiovascular system—the stress that causes training effect adaptation—is appreciably affected by how recently I’ve eaten.

Like... if I’ve eaten three hours ago, I can put out faster splits compared to if I’ve eaten thirty minutes ago at the same heart rate. Do I really have to work harder if my last meal was longer ago to get the same training effect?

It makes far more sense to me that a given wattage output on the erg corresponds directly with a given wattage input from me, and that that input intensity is what determines training effect.

Being sick or struggling in intense heat is one thing, but I can’t accept (without seeing more convincing evidence) that I have to knock two split seconds off my steady state pace just because I moved my erg outside into the cold.