What if we underestimated ourself on rpe?

[Cess]

I'm supposed to do 2x8 on RPE 8, well It (8 rpe weight) was really hard to gauge based off the initial sets, which were very hard but also primed me to move weight. So I loaded up what I thought would be rpe 8, did both sets and in reality it felt like 7-7.5. Afterward, I feel no fatigue.

Do i just wait till next workout? typically if that happens, i just do reps until it feels like rpe 8

[ropable]

Estimating RPE for a rep range is always a bit of an adventure to start with, even bearing in mind that it can vary from session to session due to factors like fatigue, etc. If I work up to a set weight that was prescribed to be RPE 8 and it felt like a 7, I'd be inclined to add some weight and repeat the set. On the other hand, if you're disinclined to repeat sets (or time is short), then just record your RPE and use it to guide your weight selections next session. I personally find estimating RPE for sets of 8+ reps more difficult anyway.

[Millzners]

When in doubt I like to work up to @9 at the specified rep range. I find @9 is much easier to feel confident about than @8. With that data point nailing down an actual @8 even weeks later is much more reliable.

You could also just do one extra rep of the initial @8 set and it should be obvious if it then became @9 or not.

[philibusters]

I'm supposed to do 2x8 on RPE 8, well It (8 rpe weight) was really hard to gauge based off the initial sets, which were very hard but also primed me to move weight. So I loaded up what I thought would be rpe 8, did both sets and in reality it felt like 7-7.5. Afterward, I feel no fatigue.

Do i just wait till next workout? typically if that happens, i just do reps until it feels like rpe 8

If there is an exercise where you really not sure if you are getting the RPE right, find a set where RPE 9 is listed and go to failure (make sure you have a spotter). As long as you do this very infrequently I don't think it will mess up your training to bad and it will teach you the feel of RPE 8, 9, and 10.