The acronym RPE stands for Rate of Perceived Exertion, a subjective scale used in fitness to measure an individual's perceived level of exertion during physical activity. Typically ranging from 0 to 10, this scale allows exercisers to assess their effort based on personal feelings of fatigue and intensity. RPE helps individuals to self-regulate workout intensity and avoid overtraining or injury, making it a valuable tool for optimizing training effectiveness. It promotes a better understanding of one’s physical limits and encourages a tailored approach to fitness.