Answer:
pursuing a goal
Explanation:
Since there are no answer choices provided I would say that this is an example of pursuing a goal. This is basically all of the tasks and struggles that an individual must go through in order to finally achieve a certain goal. It also involves gradually breaking barriers and pushing forward by increasing the complexity of the tasks until you are able to break through all of them to reach the end-goal that you have been striving for. Which is exactly what John has been doing in this scenario by gradually increasing his running time.
