Fitness is important to everyone. In public services the need is not greater, it is just that it is more likely that exercise will be avoided. You can be very busy stuck in an office and feel 'there is no time' to engage in fitness activities.
However, like absolutely every other employee, those in public service need fresh air, daylight - even when it's cloudy - and exercise of whatever sort, but daily! Apparently exercise frees up the mind and certainly improves depression, which I suspect is a hazard in corporate work.