Proximity to Failure

Training Q&A [Moderated]
1

Hey Drs,

I recently listened to podcast 205 about strength vs hypertrophy and it raised a question about proximity to failure. To my understanding, the intensity determines the type of adaptation and the volume determines the magnitude of that, so what purpose does proximity to failure serve? I know there has to be some fatigue present, but you mentioned there being a range (4-5 RIR or less) where this occurs, so why would someone pick an average RPE 7-8 over 5-6? Is it that once in this range, a rep is a rep from a fatigue and stimulus standpoint, therefore it doesn’t really matter what someone picks?

Thanks & Happy New Year!

CT

2

Determines fatigue (intraset and overall), velocity loss, and subsequent unique adaptations relative to those.

[/quote]
so why would someone pick an average RPE 7-8 over 5-6? [/quote]

For maximal strength development, it’d be hard to load a single heavy enough to drive the relevant adaptations at < 90% 1RM or < RPE 7-8.

For hypertrophy, I don’t think there’s much difference in a multi-rep set outside of maybe isolation work.

For strength endurance, there’s likely a benefit from slightly higher RPE sets.

For conditioning efforts, higher RPE conditioning efforts tend to improve speed, though these need to be balanced with a good conditioning base.

3

Hi Jordan,

What role does fatigue play in driving both strength and hypertrophy adaptations?

I’m trying to move away from the effective reps model, whereby previously if given a 10RM, I’d say the first 5 reps were useless and only the final 5 brought gainz to the table. I now think, based on the information you put out, that every rep is effective, to some degree.

Let’s consider one exercise prescription in isolation, say 1@8 followed by 5x5 70% 1RM, a fairly typical protocol. My assumption is that, for most, the first few sets if not all of the back-off work would be greater than 4-5 RIR. Most people in the industry would consider this ‘junk volume’, however, despite exceeding the maximum RIR threshold, there is obviously some stress generated from that. Whether that stress is enough comes down to the individual, their training history, etc.

So, could it be said that reaching 4-5 RIR on every set is highly likely to maximize gainzz (assuming tolerable volume, of course), and anything less might not be as good but still isn’t ‘useless’.

I know it’s difficult to talk in absolutes about programming variables, but I feel like I’m missing the forest for the trees and giving an exact proximity to failure greater priority than is necessary.

Thanks

CT