Whatever gets people through daily life as an adult. Y'know, unless nonconsensually harming people gets you through daily life, then i suggest not doing that. Seriously though, being a responsible adult is shit. Some people watch shitty tv, some people do yoga, some people do bdsm - it's all based around escaping your daily life, and daily self.
I've heard plenty of people into bondage describe it as relaxing, but B&D edging into the same cultural space as yoga is still hilarious. five nights at freddy's http://fivenightsat-freddys.com
In the community it is more commonly known as "subspace" or a submissive headspace. It is very similar to meditation, but is often about relinquishing all control and having total faith is someone else to care for your safety, so you can immerse yourself fully into the scene.
This isn't really surprising and seems similiar to float tanks, or that feeling after you drop something heavy you've been carrying like you're floating. When I was younger and would get anxious I would put my back up against a wall and push my feet against something solid to calm myself down.