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Hotwired: How the Hidden Power of Heat Makes Us Stronger from the Bestselling co-author of Outlive
Brought to you by Penguin.
Humans were born to sweat – and sweating makes us stronger.
In Hotwired, bestselling co-author of Outlive and science editor Bill Gifford explores how heat can improve our performance and our health. Combining cutting-edge science, personal discovery and practical insights, Gifford reveals how humans evolved to excel in hot conditions – and how we’ve lost touch with this ancient advantage.
He plunges into the steamy world of Finnish saunas, serves as a test subject in heat labs and tackles a 100-mile bike ride under the blazing Texas sun to show how exposing ourselves to discomfort can expand our physical and mental limits. He even explores how infrared sauna therapy and cold plunging could fight depression more effectively than medication. And he examines how, in cities around the globe, social saunas are reviving communal wellness.
Whether you want to perform better, extend your lifespan or adapt to a warming planet, Gifford shows you the incredible benefits of reawakening your body’s natural adaptability to heat and cold. Hotwired is a thrilling call to reimagine heat – not as a threat, but as a tool for strength, resilience and longevity.
'Read this book! Hotwired is a masterpiece of story-driven science that unpacks that health benefits of heat.' Dan Buettner, National Geographic Fellow, New York Times bestselling author and founder of the Blue Zones
'Bill Gifford makes the science come alive' Michael Easter, New York Times bestselling author of The Comfort Crisis and Scarcity Brain
'Fascinating. Gifford shows - through science and sweat - that heat isn't the enemy. It's a superpower we've forgotten how to use' James Nestor, New York Times bestselling author of Breath
© Bill Gifford 2026 (P) Penguin Audio 2026
Humans were born to sweat – and sweating makes us stronger.
In Hotwired, bestselling co-author of Outlive and science editor Bill Gifford explores how heat can improve our performance and our health. Combining cutting-edge science, personal discovery and practical insights, Gifford reveals how humans evolved to excel in hot conditions – and how we’ve lost touch with this ancient advantage.
He plunges into the steamy world of Finnish saunas, serves as a test subject in heat labs and tackles a 100-mile bike ride under the blazing Texas sun to show how exposing ourselves to discomfort can expand our physical and mental limits. He even explores how infrared sauna therapy and cold plunging could fight depression more effectively than medication. And he examines how, in cities around the globe, social saunas are reviving communal wellness.
Whether you want to perform better, extend your lifespan or adapt to a warming planet, Gifford shows you the incredible benefits of reawakening your body’s natural adaptability to heat and cold. Hotwired is a thrilling call to reimagine heat – not as a threat, but as a tool for strength, resilience and longevity.
'Read this book! Hotwired is a masterpiece of story-driven science that unpacks that health benefits of heat.' Dan Buettner, National Geographic Fellow, New York Times bestselling author and founder of the Blue Zones
'Bill Gifford makes the science come alive' Michael Easter, New York Times bestselling author of The Comfort Crisis and Scarcity Brain
'Fascinating. Gifford shows - through science and sweat - that heat isn't the enemy. It's a superpower we've forgotten how to use' James Nestor, New York Times bestselling author of Breath
© Bill Gifford 2026 (P) Penguin Audio 2026
- GenresNonfictionHealthScience
10 pages, Audible Audio
Published March 19, 2026
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Displaying 1 - 5 of 5 reviews
April 12, 2026
Five stars. Read it in two days.
Great book to understand the science behind sauna vs the pseudoscience.
Gifford balances three things really well: peer-reviewed research, cultural history, and his own experiences. He’s a good writer. Self-deprecating, curious, never preachy.
The myth-busting was great - “sweating out toxins”, hype on cold plunging, etc. Gifford clarifies what’s real from what’s marketing.
Great book. Quick read. Engaging.
Great book to understand the science behind sauna vs the pseudoscience.
Gifford balances three things really well: peer-reviewed research, cultural history, and his own experiences. He’s a good writer. Self-deprecating, curious, never preachy.
The myth-busting was great - “sweating out toxins”, hype on cold plunging, etc. Gifford clarifies what’s real from what’s marketing.
Great book. Quick read. Engaging.
Want to Read
February 5, 2026Won and received a copy through a Goodreads Giveaway!
April 17, 2026
Hotwired~~~~
I eagerly picked up Bill Gifford's new nonfiction book Hotwired: How.the Hidden Power of Heat Makes Us Stronger. He's a science writer in his fifties who wouldn't have thought about writing about our crucial need for heat acclimatization and therapy if it hadn't been for his long-time publishers suggesting he do so. The importance of challenging our thermoregulators like people did before, basically air conditioning is mostly overlooked or casually ignored until the last handful of years. He went on an investigation into saunas, hot tubs, hot yoga, and clinical trials for heat or heat and cold therapy and has never felt better in his cognitive and cardiac function. His mood is much uplifted too.
Gifford learned that you need to get your body temperature up to 101 degrees Fahrenheit for our beneficial heat shock proteins to develop and do things like kill the COVID virus, greatly help reduce chances of strokes and dementia, and decrease anxiety and depression.
I found the book fascinating. I don't know if a sauna would be safe for me with my incomplete spinal cord injury that makes me faint if I feel too warm from eating/digesting too much greasy stovetop-popped popcorn. I need to research this because heat acclimatization therapy would really loosen my tight muscles from spasticity.
If you want to try this therapy, read Hotwired first and realize that Gifford kept track of his body temp with a rectal thermometer in the clinics and some other way, I think, when he rode the Hotter 'n Hell Hundred in Texas in August 2023.
Gifford used to hate to sweat, but now he craves being able to do it. He can enjoy hot days when others are sheltered indoors and has the bike trails to himself. This experience has positively changed his life, to his amazement, and he urges his readers to become acclimatized to hot weather as the climate threatens us with terrible heat waves that lingers and extreme weather patterns are only increasing. We evolved to be able to handle extreme temps much better than any other creature, being the one with the most sweat glands, so we need to start sweating.
Highly recommended!
I eagerly picked up Bill Gifford's new nonfiction book Hotwired: How.the Hidden Power of Heat Makes Us Stronger. He's a science writer in his fifties who wouldn't have thought about writing about our crucial need for heat acclimatization and therapy if it hadn't been for his long-time publishers suggesting he do so. The importance of challenging our thermoregulators like people did before, basically air conditioning is mostly overlooked or casually ignored until the last handful of years. He went on an investigation into saunas, hot tubs, hot yoga, and clinical trials for heat or heat and cold therapy and has never felt better in his cognitive and cardiac function. His mood is much uplifted too.
Gifford learned that you need to get your body temperature up to 101 degrees Fahrenheit for our beneficial heat shock proteins to develop and do things like kill the COVID virus, greatly help reduce chances of strokes and dementia, and decrease anxiety and depression.
I found the book fascinating. I don't know if a sauna would be safe for me with my incomplete spinal cord injury that makes me faint if I feel too warm from eating/digesting too much greasy stovetop-popped popcorn. I need to research this because heat acclimatization therapy would really loosen my tight muscles from spasticity.
If you want to try this therapy, read Hotwired first and realize that Gifford kept track of his body temp with a rectal thermometer in the clinics and some other way, I think, when he rode the Hotter 'n Hell Hundred in Texas in August 2023.
Gifford used to hate to sweat, but now he craves being able to do it. He can enjoy hot days when others are sheltered indoors and has the bike trails to himself. This experience has positively changed his life, to his amazement, and he urges his readers to become acclimatized to hot weather as the climate threatens us with terrible heat waves that lingers and extreme weather patterns are only increasing. We evolved to be able to handle extreme temps much better than any other creature, being the one with the most sweat glands, so we need to start sweating.
Highly recommended!
April 13, 2026
A terrifically engaging read that speeds by but leaves you with a lot to think about. As in his earlier book “Spring Chicken,” Gifford puts himself under the microscope on the readers’ behalf — and to great effect. A quite funny, whip-smart primer on little changes most people can make in their lives to better move through a warming world. Highly recommended!
April 4, 2026
I enjoyed this one - good information on benefits of heat therapy. Liked that the author shared personal experiences.
Displaying 1 - 5 of 5 reviews