RPE stands for Rate of Perceived Exertion. Sounds fancy, but it’s actually quite simple and a concept everyone is familiar with. It’s a scale that is used to measure the effort when you’re exercising, what people commonly know as intensity. When someone says that a set was really intense, they mean the set was really hard. But by definition, intensity means the percentage of your 1rep max, not the actual effort you put in into a set. RPE is the rating of your feeling of effort during a set.
This isn’t a new concept. The original RPE scale was introduced by Gunnar Borg on a scale of 6-20, but it was mostly applied to clinical diagnosis and it wasn’t very practical to strength training (1). The first person to ever mention RPE in a strength training context was Mel Siff in his “Supertraining” book. However it still didn’t offer any precise, methodological way of actually measuring it and applying it. (2)
That above came with Mike Tuchscherer in 2005. Not only is Mike an amazing lifter (totaled [email protected]) with several World Records, but also an extraordinary coach, guiding over a dozen competitors at the world championships, and multiple world record holders in Powerlifting. And every single one of his clients uses his RPE system.
Mike Tuchscherer wrote a full book dedicated to the method of RPE training, called “The Reactive Training Manual”. It gives auto-regulating templates, teaches you how to track your training, how to manage stress and fatigue, how to program each cycle, and much more. It’s a wonderful resource to understand the philosophy of auto-regulation and how to apply it to your own training. Unfortunately, that book is out-dated, since Tuchscherer’s views changed over the years, and he kept adapting and improving his methods.
In more classic programs, your lifts are per-calculated based on a previous max or estimated max. That is great in theory, but the big problem with this is that in the specific day you’re lifting, your daily max is different than the max you did or calculated weeks ago. Stress, sleep, food intake, even the time of the day will impact your lifting. You might be calculating your lifts based on a 400lb squat you did 5 weeks ago, but if you tried it today, you’d only get 380lb. So when you go to lift something that is based on a max 20lb higher than you can actually do… you’re going to have a bad time.