Bisjep,
Thanks for the post. I’ll respond in order:
Intensity is defined as the percentage of maximum that a given effort is. In lifting, if you can squat 600, but do sets at 300- the intensity of those sets is 50%.
RPE is a subjective rating of exertion that can be a proxy for objective intensity. Back to our 600lb squatter example for a moment, it is likely he is unable to squat 600lbs everyday of the week. Rather, he likely has a range of performance that varies day to day. Using a percentage based program with static prescriptions on a dynamic variable can lead to issues. For example, if our 600lb squatter is told to squat 80% for 4 sets of 4 repetitions then he is banking on using 480lbs for his sets.
However, if on this particular day he would only be good for a 550lb squat (and 10% swings in performance are very common in strength/power sports per the data on such things) and he still using 480lbs - he will now be squatting at 87%- a near 4 rep maximum for 4 sets. He may be able to complete this task, but it may not produce the appropriate stress and fatigue needed to actually get better. This workout would be more of a performance display than training.
Now to your questions:
- Aside from short heavy sets to gain skill at short heavy sets, all training requires adequate volume at an appropriate intensity.
Short heavy sets are part of the training stress so we can’t really ignore them, but yes all training requires appropriate volume and appropriate intensity.
- Adequate volume means: keep adding difficult sets in any rep range until you are getting stronger, with an eye to your recoverability.
No. I take issue with “any rep range”, how you define “getting stronger”, and the recoverability piece.
- Appropriate intensity means: enough weight such that all muscle fibres are firing at the end of the set. Beyond that is just adding to your recovery burden.
No. Wouldn’t you want a bunch of motor units firing at the beginning of most sets too?
- An intensity of 60-70% (and below 85%, except to train for 1RMs) is enough to recruit all motor units within some number of reps.
Eh, that’s too complicated to really say it like that.
The question is, how many reps? (For the individual, on that day.) Can I learn what it feels like when all units are engaged? Does it correspond consistently to a particular RPE? Or at least, can I be confident that any RPE above X (7?) is above the threshold, even if I don’t know for sure that X is the threshold itself?
How many reps for what? You won’t “feel” anything that is reliable when a high amount of motor units are being recruited and there are multiple different ways to arrive at the same end point- motor unit recruitment- though the end result with respect to performance is different.
Since 10@8, 1@8, and 10x1@8 are not the same stress, it seems that, as useful as it is, RPE is only an indirect measure of training stress. Can there be a more direct scale? – maybe in the future, with enough data on how different people respond? Or have I just got very confused?
Well 10 @ 8 and 10 x 1 @ 8 are the same volume, but different intensity…so we should expect that they aren’t the same. 1 @ 8 is different than both conditions for both variables and we wouldn’t expect it to be the same either.
A more interesting comparison would be 3 sets of 10 reps @ 65% vs 10 sets x 3 reps @ 65%. I would predict no difference in strength or hypertrophy since the volume is the same and the overall fatigue generated is probably similar. Both are too low to really drive strength improvements optimally either.
Now, a more interesting discussion would be 10 sets x 3 reps @ 75% vs 6 sets x 5 reps @ 75%. I would again expect no difference in hypertrophy, but probably a node to 6x5 @ 75% for strength given the intraset and residual fatigue factors driving some additional motor unit recruitment. That difference might be mitigated by shorter rest periods on 10 x 3 reps and one could argue that more sets= more practice.
Still, I haven’t seen good data fleshing this out and haven’t been able to discern any reliable trend from my own practice.
So for now, 70-80% and 90-100% are the money ranges for most strength training IMO. 80-90% is a gray zone where you grind your way to obscurity.