Rate of Perceived Exertion (RPE) is a great tool that we can use to help individualize training, which is obviously helpful in a group scenario.
But it does have limitations, most importantly it’s entirely subjective, based on the person setting the RPE for the workout, and for the person doing the workout as well.
For example, if Murph is a really strong runner, his RPE doing the exact same running workout as Fran, at the same pace would be significantly lower. This gets even hairier when we have to think about people beating time caps that we’ve imposed for class management.
While we do use the 1-10 scale with 6 being a comfortable effort you could maintain for hours, and 10 being an effort you can only maintain for a very short time, for conditioning it can be more helpful to think of this in terms of 3 levels of effort.
Level 1: A Sustainable effort (6-7 RPE) that you could maintain for hours, and stays fairly consistent throughout the bout of exercise, over 20 minutes.
Level 2: A Challenging effort (7.5-8.5), starts off lower, builds and gets fairly uncomfortable in the last minute or two, 8 to 20 minutes.
Level 3: A Hard or Tough effort (9+), starts off uncomfortable and gets even worse, anything under 5-6 minutes.
The 7-8 RPE range of the scale is the most difficult to prescribe, since it will vary wildly throughout the duration of the workout and should be thought of more as an average for the time domain. To maintain the same pace, someone might start a 12 minute workout at a 6.5, do minutes 3-10 at an 8, then minutes 10-12 at a 9.
So why use it at all for conditioning in a group program if there is so much gray area? As you have probably noticed with our programming, we should be varying our total intensity in given training zones throughout the week, month etc. While it’s far from an exact science, RPE is a good tool if someone isn’t able to monitor their heart rate while working out. RPE is also a great way we can allow a member to autoregulate their training, if someone is not feeling great, their RPE will be lower than it would be on a good day. Psychologically this is important to give someone a hall pass to just move, instead of going full send. For strength work this is the same reason we write “heavy double” instead of a 2RM.