This…INOL is a pretty good gauge of stress from strength training. The problem that I’ve found with it is that it doesn’t differentiate between 5 sets of 2 with 90% and 2 sets of 5 with 90%.
I have taken an approach where I set a max tss achievable per set (arbitrarily set at 10), then estimate the percent of a rep max at that percent of my 1rm. I then treat this like an IF.
So a set of 5 at 80% 1rm is 80/85 = .94IF, given that a 5rm is roughly estimated at 85% of 1rm.
Then tss for a set is just 10 * IF * IF.
The insight for treating the set as the atomic unit of stress came from the stuff that Greg Nuckols has written, which says that “number of hard sets” seems to be the most predictive of hypertrophy and strength outcomes.