I've found the same outlet in racing cars, soccer, and working out. I've actually told people before that I think the reason racing helps so much is that you are absolutely 100% focused on the task at hand when you're being the wheel, which means no work or personal stress at all for the time you're on the track.

Soccer is one of the few things I do that allows me to interact with people in a completely different professional field.

And working out gives me a sense of accomplishment completely divorced from my career, which I can carry with me all day in the way I feel physically.

All of these help provide context to my life (and reality), which I think helps me deal with stress at work. Another outlet my dad once suggested was reading fiction as a way to remind yourself there's more to the world than your world and to keep things in context.

Some ask how you have time for these activities with work. I ask how you can work without these activities.

Edit: Formatting and expansion.