Aaron Hartman, MD recommends holotropic breathwork for stress and anxiety. He claims 20 minutes daily plus a weekly one-hour session can work as well as SSRIs, and suggests fitting short sessions around meals or rest.
Chapters
Holotropic breath work is great if you're really revved up and you're really stressed to take the edge off of that. And then the one hour one is using your breath as a therapy session. Usually you need to do that at home. That's a huge powerful health hack. If you want to start working on your stress, just have some daily breath, work around your meals, your rest. If you get stressed during 20 minute and then once a week doing a one hour Holotropic session, that by itself will be more powerful than any drug you can potentially get, minus benzos which have the loss side effects. But as far as your typical SSRIs, that bit by itself worked way better than a Prozac or Zolol for helping with your stress or anxiety.