How to measure volume: per SRA cycle or per time period?

[Marenghi]

@marenghi the cycles are not arbitrary, I'm coming to the opinion that the length of SRA cycle can be controlled by dosing the stress. TM and HLM for example both force a longer SRA cycle with their heavy/volume day, then the rest of the week is dialed in towards timing the recovery for the next heavy day. If your schedule / motivation permits higher frequency, then you can take advantage of shorter SRA's triggered by small doses of stress. I guess the high frequency approach would stall out at some point for the exact same reason(s) that the SS novice LP does. (And I'm not completely sure why that is, but I guess it must be some combination of overtaxed recovery and insufficient stress).
If we're constrained to a maximum of four sessions per week, programming for a longer SRA cycle might be our only option.

Yes, I agree; my point is there is no *exact* overload event that leads to a binary 0/1 adaptation of a certain fixed amount in a fixed timeframe. Thats only what the way of training and displaying performance ("try a new 5RM PR on day X") leads us to suggest: If we get the new PR - then we´re led to believe we have adaptation exactly within that timeframe (not the day before, because we didnt try a new 5RM PR). We also dont know if fatigue just masked a new PR if we fail. There is also no open-end measurment of the quantitiy of the improvement - it only can be "getting the 5reps in with the new weight or not". And thats why a time-dependend measure of volume makes more sense than a cycle-dependend when comparing programs. Because thats what drives adaptations.

For hypertrophy at least, its well researched that the session threshold is pretty low for MPS. Even in trained lifters it was shown as little as one set @70% 1RM triggers it. I dont know of any pure strength studies - but strength is built indirectly by a good deal of hypertrophy anyway.

Volume-matched programs of high session volume/low freq, and low session vol/high freq are both similar and doable long-term (see Mike Tuchscherers reactive training system). For strength, high frequency (>= 2x/w/muscle or movement) even seems to work very well. For hypertrophy, higher frequency seems to allow more volume, while frequency itself is not that important (the effects probably plateuing beyond >2/week).

[George Christiansen]

Of course we cannot necessarily narrow down the exact length of an SRA cycle, but that doesn't mean that it is somehow an arbitrary length of time.

The SRA cycle length is fixed (within a range maybe, but still fixed at that range) based upon training "age", which is why you cannot just take what would constitute an overload event for someone with a week long SRA curve and expect spreading it out to two weeks or condensing it to a week to work.

[Marenghi]

Sure. Of course you take training age into consideration when measuring with absolute timeframes. As you said yourself, advancement is a range. So absolute time gives you a better view of assessing different speeds of advancement, overall work capacity and are more apt to compare different programs for similar training levels.

Thats why I prefer absolute timeframes, but for a single person´s training, it doesnt matter much anyway. The points Austin and Jordan mentioned in their posts have more impact than that and are what show slight differences in programming for intermediates.