When carrying out an aerobic activity, like walking o riding a bicycle, the intensity of the exercise is related to its degree of difficulty; in other words, it is a subjective experience based on breathing rhythm, perspiration, and muscle fatigue.
There are two ways of measuring the intensity of exercise:
1.- How you feel: physical exercise intensity is a subjective measure because it is based on personal perception, on the effort you feel to be exerting. Two people may feel two entirely different things even if they’re performing the same activity. For example, what seems to you like a really hard race will feel like a walk in the park to someone that’s in better shape.
2.- Your heart rate: a more objective measure of physical exercise intensity. Usually, the greater the rhythm, the greater the intensity.
Studies show that perceived effort is closely related to heart rate. Therefore, if you feel that you’re training hard, your heart will most likely beat very fast.
All of this means that you can choose any of these two methods to measure the intensity of your physical activity. If you’re a tech buff and you care about numbers, you can opt for a heart rate monitor or an activity wearable. For those of you who believe to be in sync with your body and trust your sensations, these devices will still come in handy as a good way to both manage physical effort and improve the accuracy of your custom training plan.