In the 10/20/Life book they talk about doing, for example RPE 7 with one top set. So would I do something like 60%, 65% and then for my last set do 70% (RPE 7)?
As far as RPE 7, it could be ballparked at 70%, but that’s going to change depending on the reps. RPE 7 for a single and RPE 7 for a set of 5 are going to be very different weights. Just like the guys above said, 7 should mean 3 in the tank left from what was going to be a top set. RPE 7 for a single is weight that would be RPE 10 for a set of 4, and for a set of 5 it would be for a set of 8
For the second part of the question, the way you build up to it is up to you. Early in the program with sets of 5 I’m not concerned about how much weight I’m pushing, I’m just trying to get work in and practice form. Warming up and then having the working sets start not too far from what the top set will be can be really helpful for that…. if your top set of 5 at RPE 7 is 315, then warm up and have your first set be 275, then 285, and make 10 lb jumps until the 5th set is 315. You can practice your form and stimulate muscle with the those kind of weights. If it’s going for a top single and I’m more concerned about putting up a good number, I would make larger jumps in the 20-30 lb per set range rather than 10lbs…. This depends on the lift of course too, squats and deads will be making bigger jumps because you can lift more vs bench.
1 top set means exactly one top set at that RPE.
As JB mentioned, the RPE indicates a level of effort, not a bar weight. RPE 7 today and RPE 7 after being sick with a cold would be different bar weights, but the same effort level. RPE 7 would mean 3 reps left in the tank, RPE 6 would mean 4. an RPE 10 would be a max. No more reps could have been done.
Your weight choices during your build up sets will have a large effect on the amount of weight you can move for that top set. Making 5lbs jumps and starting a bit heavier would accumulate more fatigue than making 50lbs jumps and starting lighter. It all depends on the day. Ideally, you’ll want to find a point in between my two examples.
70% could be a rough guide but using RPE does not involve percentages. Your goal is to have 3 reps left in the tank on that day. For example if you did 225×5 at an RPE of 7, it would mean you think you could have done 8 total reps that set.