Personally? Fitness is very important as I do not want to end up with obesity, premature dementia or depression. I schedule part of every day for exercise of some sort. It doesn't much matter whether it is a good walk, a swim or a gym session or a class such as Pilates, Ballet, or Zumba.
These last are all good for core strength. What has been recognised is that those who are long-lived have exercised, not just physically but mentally. It is important to take advantage of opportunities in both respects. So my anser to you is that fitness plays a role in my daily life like food, rest, work, socialisation and recreation.