1. shane has been running local 5ks and is looking for a new challenge. explain how shane would utilize the three principles

of exercise when developing his cardiovascular system to meet the new challenge of preparing for a half marathon

First Shane need to state his plan of exercise and overload it.

Explanation:

In  cardiovascular training there are three principles. The first, to set a program, second to register the progression, and the third, is the specificity.

In Shane, he has to complete his program and every training that he has, he need to register time that he took to complete the same distance, but in less minutes, so if it is written, is easy to observe the progression of the training.

Finally in the journal is necessarily to specify with details certain circumstances like less time, less effort need to complete the 5k, etc.

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the right answer is: time