Cold Showers & Cold Plunges

Cold water immersion at 10-15 degrees Celsius triggers a massive norepinephrine spike — up to 530% in some studies. Regular cold exposure has been shown to reduce inflammation, improve mood, boost immune function, and increase brown fat activation. A 2022 meta-analysis in the British Journal of Sports Medicine confirmed benefits for recovery and mental health. The Wim Hof crowd was annoying about it, but they weren't wrong.