Respuesta :
The fitness training principle used for increasing effort is known as reversibility. Details about reversibility can be found below.
What is reversibility?
Reversibility is any adaptation that takes place as a result of training will be reversed when you stop training.
Reversibility as a concept states when you stop working out, you lose the effects of training.
Since reversibility is not something people aim to achieve, it is, therefore, a principle used for increasing effort in fitness training.
Learn more about reversibility at: https://brainly.com/question/14273886
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