Jack cannot run as fast as Paul. He decides to go at his own pace and not run with Paul. Which principle of fitness is he following? Progression
Overload
Individuality
Reversibility

individuality

Explanation:

(you can ignore this its just the deffintion of  individuality)

This is a crucial principle, the fundamental fact that everyone is different! Everyone responds to training in a different way. If you are walking or cycling with a friend, and doing exactly the same amount of training, don’t be concerned if one of you gets fitter faster than the other – this is what individualisation is all about.

It might be that one of you is having some pressure at work or difficulties at home, but wherever it is, it’s surprising what can affect your training. Some days your training can go really well and the next day, even though it was exactly the same length workout, it can be a nightmare. This is individualisation.

no. dot product   =0 when vecs at right angles