Zone 2 cardio training is a type of steady-state aerobic ... Your rate of perceived exertion (or RPE)—a scale used to measure the intensity of your exercise, from one to 10—is a one or a ...

RPE stands for Rate of Perceived Exertion, and it’s a self-monitored scale of how hard you find a workout, from 1-10. Hoggins advises that zone 2 training would be around 3/10 on the RPE scale.

You create more ATP as you exercise, and which type of fuel your body uses is determined by which heart-rate zone you exercise ... your heart-rate, and RPE (Rate of Perceived Exertion).