Measuring Indoor CO2 and Cognition

James Nestor is a science journalist and the author of the international bestseller Breath: The New Science of a Lost Art, with more than three million copies sold in 44 languages.

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Timestamps:

[00:00:00] Start.

[00:01:37] Why I waited years to interview James about Breath.

[00:02:35] Maurice Daubard: The mysterious 90-year-old who preceded Wim Hof.

[00:05:01] Tummo breathing: Ancient Bon Buddhist heat generation.

[00:08:13] James’ personal breathwork practice and the Wim Hof method (with warnings).

[00:09:25] How breathwork cured James’ chronic respiratory issues.

[00:11:46] Sudarshan Kriya: The weekend workshop that changed everything.

[00:16:56] My nine-minute breath hold experiment (hyperbaric chamber edition).

[00:18:57] Post-book revelations and angry doctors’ offices.

[00:20:41] The ADHD-breathing connection: A controversial Venn diagram.

[00:22:00] DIY breathing assessments for kids.

[00:25:55] Mouth tape: From hostage situations to sleep optimization.

[00:28:48] James’ seven-year mouth taping commitment.

[00:31:14] CO2 levels: Your LEED-certified hotel is suffocating you.

[00:36:50] Monitoring CO2 with the Aranet4 and building a CO2 database.

[00:39:51] James’ travel kit: Red lights, granny packs, and a Soviet-era PEMF device.

[00:51:59] In Weirdville, eyes sing The Body Electric.

[00:52:58] The supplements included in David’s granny packs.

[00:54:16] Natto vs. nattokinase.

[00:56:18] Athletes and breathing: The BOLT score explained.

[01:03:25] LeBron James’ alternate nostril breathing and diaphragmatic dysfunction.

[01:04:47] Inspiratory muscle training and the back soreness warning.

[01:08:47] The Relaxator: An adult breathing pacifier for focus.

[01:12:54] San Francisco Writers Grotto and the trustafarian invasion.

[01:16:10] Writer’s block: A convenient excuse for hobbyists.

[01:19:04] Cutting the corporate cord: James’ visceral “I quit” moment.

[01:23:25] The freediving story that launched a book deal.

[01:25:41] Deep‘s disappointing launch and publisher betrayal.

[01:28:10] Breath: From 290,000 words to 85,000 in a house in the woods.

[01:31:51] Finding the skeleton: The Stanford experiment as through-line.

[01:35:44] Prayer and coherent breathing: The 5.5-second secret.

[01:38:44] James’ critique of breathwork culture and barriers to entry.

[01:41:07] Sleep optimization: SnoreLab, side sleeping, and incline bed therapy.

[01:44:56] Parting thoughts and where to find James and free breathing protocols.

*

Show notes for this episode: https://tim.blog/2025/09/30/james-nestor-breath/

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