RPE
RPE (Rate of Perceived Exertion) is a supjective scale used to measure the intensity of exercise. 1 It ranges from 1 to 10, where 1 is very light activity and 10 is maximal effort.
For example, an RPE of 8 means the person is working hard but could still perform 1-2 more reps before reaching failure.
There's an excellent breakdown of RPE by Jeff Nippard here 2.
Sources
- Kenzie Mahaffey, "The Rate of Perceived Exertion (RPE) Scale Explained", National Academy of Sports Medicine, https://www.chicagomanualofstyle.org/turabian/turabian-notes-and-bibliography-citation-quick-guide.html.
- Jeff Nippard, "How To Tell If You're Training Hard Enough (Using Science)", YouTube, https://youtu.be/deDlhPmT2SY?si=_i66cFM0nOS_RBNz.