Resting heart rate 68 to 56: what changed in my dev work

I normally write about web frameworks, WebAssembly, and JavaScript internals. And I normally don't publish on a Saturday. But I've been wanting to write this for a while and today I woke up inspired, so here it is. This isn't a technical article. It's personal. But I genuinely believe it can help a lot of people, especially developers and founders who spend long hours in front of a screen and feel like their brain gives up before their schedule does. I want to talk about the things that changed my daily performance more than any tool, framework, or productivity app ever did. Not hypothetical stuff I read on a blog. Things I've been doing for months (some for years) that produced measurable, repeatable differences in how I work. Here are the numbers first: Resting heart rate: 68 → 56 bpm Breathing rate: 14-16 → 8-10 breaths/min Deep work blocks: ~90 min max → 3-4 hours consistently Post-meeting recovery: 20-30 min → basically instant None of this came from a supplement, an app, or a cou