Whether the results of exercise are worth it or not will be seen from a person's fitness every day. He can anticipate the work he does, because with a good portion of exercise, you can be sure that every day he will be able to do good activities and be able to work in a portion that can still produce good work. Good.
But sometimes exercise must also be measured by one's own abilities. There are those who are able to do sports that are quite draining, but there are those who are not able to end up reducing the portion of the load they do. Everything is the same and the results will still be useful for him whether there is a burden or not. The most important thing is that the activity is continuous.