Discipline.
You may think it’s easier for someone to be disciplined in fitness if they were bought up doing martial arts? Maybe so… But if you are disciplined in fitness you can use the same strategy to be disciplined with your money/time/housework/studies. Anything you chose.
Most of us have problems we talk about as if it affects our whole lives, it becomes our identity i.e., I am not organised, I’m never motivated, I am not disciplined, etc, etc.
In actual fact, our problems are that we don’t necessarily ‘DO’ ALL the time. Just some of the time. And if we know how to do it some of the time, we can elicit the same strategy to do it all of the time. Or at least with the areas we want to use it.
Remember discipline is a choice.