I consider fitness to be something that grows with the client. Clients come to us to improve. They want to get more out of life. Fitness is being capable of doing what a person needs to do and then some. People often come to me so they can enjoy an activity or traveling or family time more. Once they find these things more enjoyable. I try to encourage them to see fitness as part of their life as well and to continue working toward ever improving goals.
There are a ton of comparative measurements you can do, to see how your clients stack up against normative data.
But personally, I like tend to o a thorough assessment of strength, endurance, flexibility and balance without comparing client’s data to other people. What do they really want to be able to do? What skills do they need to have in order to do that? What other skills that they’re less interested in but will help lead to well-balanced health should be focused on (for example, if client wants to get stronger, I’ll help them with strength, but we’ll also set supporting flexibility and balance goals, because they indirectly support).