intensity question

I'm sure this is an old question, but maybe it's an evergreen topic,as they say.

Just how hard should each exercise be? I mean, I have done sets of pushups where I'm grunting and gasping as I do the last few reps-- struggling not to break form. These are not fun btw!

But more importantly --  I find that work outs like that are usually related to a plateau. I'm feel like I'm trying to push myself through to the next level with grit, rather than letting physiological changes pull me through.

What I've been doing lately is that when I find myself at that point is I regress a little bit, and work back to that level at a slowish rate of increase.

Does that make sense? Or should I be screaming at the end of each set with a no pain no gain attitude? 

Hey Paul,

There's a time for really hard work, super easy sessions, and everything in between. It sounds to me like you've been pushing too hard for too many sessions, hence the backward progress. What you need now is a period of backing off, so select the "Too Hard" smiley face and regress. 

In other cases, pushing hard can help you bust through a plateau. There is no one answer to this; adapting to training is a constantly changing process. Give my suggestion a go and let's keep an eye on how you feel over the next couple of weeks. You may need to take a week off to let your body recover, but let's try simply backing off first using the smiley faces. 

that's more or less what I've been doing, but I've actually been regressing within a step.

For example,on pushups, I'm currently at 5x9. I've been doing extra in every work out to try to get to 5x12 before clicking easy on 5x9. 

(Otherwise, if I click easy on 5x9... well, there's no way I can do 5x12 the next night.)

So I've been doing 1x10, 4x9; and then 2x10, 3x9; and then 3x10, 2x9. etc.

That was working fine for a while, but each session was just a bit harder.When I got to 2x11, 3x10, well, I was dying.

So I regressed back to 5x9 last night. It was easy, but i think I needed an easy night. so, I'll work my way up again, see how it goes.