General Programming question... pure curiosity

[Epictetus8540]

With a linear progression, we constantly move up in lifting weight as long as we can, at regular intervals, with the primary result of of increased strength.
As we progress, fatigue increases and rest periods must increase to compensate for that, in order to continue our strength progression.
Just out of curiosity, what is the physiological adaptation if at some point...
1) we stop adding weight, and start adding sets? For instance, 3x5 at some give weight becomes easy, and we move up to 5x5 or 6x5 or whatever? I presume we stop getting stronger, but would endurance be the primary adaptation in that scenario?
OR
2) we stop adding weight, and start reducing the rest periods between sets? Endurance as well?

And is there any conceivable scenario or sport specific training where some coach might recommend these sort of modifications?
I am not a coach, and this is not something I am planning on doing. This is purely academic curiosity.

Thanks in advance.

[Ivan Stepic]

Any of those modifications will likely work only for a very very short period of time for gaining strength.

Conditioning effect will be gained from both modifications, yes. But there are better ways to develop conditioning if that's what you want. So since it's not a good strategy for conditioning or gaining strength, I can't think of any scenario where one would use such modifications. Maybe I'm wrong.

[Mark Rippetoe]

You're not wrong.

[philibusters]

Any of those modifications will likely work only for a very very short period of time for gaining strength.

Conditioning effect will be gained from both modifications, yes. But there are better ways to develop conditioning if that's what you want. So since it's not a good strategy for conditioning or gaining strength, I can't think of any scenario where one would use such modifications. Maybe I'm wrong.

It wouldn't be an idea hypertrophy program, but it would likely also give you some additional hypertrophy benefits.

[Mark Rippetoe]

Why do you say that? Because conditioning makes you hyooge?

[bikesandcars]

I did stronglifts 5x5 2 years ago. I made quick gains on the squat after a decent back-off to 135, but as I got up to 185 I couldn't recover between days and the plateau was very frustrating. I like 3x5 much better, especially being over 40 I feel it's quicker, less annoying, and provides enough stimulus to grow without burning me out. I can only imagine this is even more true if you lift serious weight.

[Mark Rippetoe]

It's almost like we know this shit, huh? And 185 is not very strong. Our program works better than that.

[bikesandcars]

It's almost like we know this shit, huh? And 185 is not very strong. Our program works better than that.

Your program has reinvented my current training philosophy. After mucking about with so much other misdirection I finally feel confident this is going to take me somewhere if I work, eat and sleep. We'll see where it goes but yes, you know your shit