A self-reported score of how hard exercise feels.
RPE is a patient-reported number describing how hard an effort feels, using either the Borg 6–20 scale (anchored loosely to heart rate) or the simpler 0–10 CR10 scale. It gives a quick subjective readout of exercise intensity without needing any equipment.
On the clinic floor it lets you gauge and adjust intensity in real time, especially when heart rate is unreliable (beta-blockers, arrhythmia, deconditioning) or when load monitoring across a rehab or return-to-sport programme needs a simple shared language with the patient. Multiplying RPE by session duration (session-RPE) gives a practical training-load figure you can trend week to week to guide progression or flag overreaching.
Ask the patient to rate the effort immediately after a set, exercise bout or full session against the chosen scale, having briefed them on the anchors beforehand (e.g. 6/20 = no exertion, 20/20 = maximal). For session-RPE, multiply that single post-session rating by session duration in minutes to get an arbitrary-unit load score, tracked over time to spot spikes in acute:chronic load.
RPE is subjective and shaped by motivation, mood, prior experience with the scale, pain, and fear-avoidance, so values are not directly comparable between individuals and need consistent anchoring instructions to be reliable within one person. It also lags true physiological strain in some contexts and can be gamed or under/over-reported, so it should support rather than replace objective markers where those are available.