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\title{
    \large \textbf{BOOK REVIEW} \\
    \huge \textit{Oxigen Advantage} \\
    \large \vspace{0.5em} Patrick McKeown
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\author{Reviewed by: Philipp Waibel}
\date{\today}

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% \section*{Quick Info}
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%     % \item[Publisher:] Name of Publisher (Year)
%     % \item[Genre:] Non-fiction / Fiction / Sci-Fi
%     \item[Pages:] 350 pages
%     \item[Rating:] \textcolor{orange}{★★★★☆} (4/5)
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% \section*{Summary}
% I really liked this book for it's simplicity. It was very well written with an easy language, yet the tools and techniques were very science backed, which for me as a science heavy person is a big plus. The author does a very good job in giving you a good foundation on how the breath acts on your system and how to change it to have the best result.

\section*{Review}

Patrick McKeown’s The Oxygen Advantage presents a counterintuitive yet compelling thesis: most of us breathe too much, and this chronic overbreathing is silently undermining our health, fitness, and mental clarity.

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The book’s central argument revolves around the misunderstood role of carbon dioxide. Contrary to being a mere waste product, CO₂ is essential for releasing oxygen from red blood cells to the body’s tissues. When we overbreathe (often through the mouth), we expel too much CO₂, causing blood vessels to constrict and oxygen to bind tightly to hemoglobin instead of being delivered to the brain and muscles. McKeown therefore advocates "breathing light to breathe right" — gentle, quiet, diaphragmatic breaths through the nose to restore optimal CO₂ levels and improve oxygenation.

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To help readers gauge their breathing efficiency, McKeown introduces the Body Oxygen Level Test (BOLT), a simple measurement of how long one can comfortably hold their breath after an exhalation. A low BOLT score correlates with symptoms like nasal congestion, fatigue, poor sleep, and excessive breathlessness during exercise, while the goal is a score of around 40 seconds. The book then systematically outlines functional breathing techniques to raise this score, including taping the mouth during sleep to enforce nasal breathing, breath-hold exercises that simulate high-altitude training, and warm-up drills designed to create a beneficial "air hunger".

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For athletes and fitness enthusiasts, the program offers a distinct edge. McKeown explains how nasal-only breathing during training can improve VO₂ max, increase carbon dioxide tolerance, and even naturally stimulate red blood cell production, mimicking the effects of "live high, train low" altitude camps. Several elite sports stories are woven into the text as evidence, alongside anecdotes about ordinary people who have reversed asthma symptoms or shed weight without dietary changes.

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\section*{Summary}
In summary, The Oxygen Advantage is a life-changing read for those willing to sift through the repetition to get to the program itself. The information on nasal breathing and carbon dioxide tolerance is genuinely transformative and has demonstrably helped many people improve their asthma, sleep quality, and athletic performance. It is best approached as a manual to be practiced rather than a book to be read once; as one reviewer noted, it should be treated as a textbook where repetition aids learning. I would readily recommend it to anyone struggling with breathlessness, chronic fatigue, or suboptimal fitness, with the gentle advice to skip through the redundant stories and focus on the exercises—because in the end, learning to breathe less really can help you achieve more.


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\section*{Key Takeaways}
\begin{enumerate}
    \item The "Breathe Less" Paradox
The book’s most significant insight is that "overbreathing"—taking deep, heavy breaths through the mouth—doesn't actually get more oxygen to your cells. Paradoxically, it flushes out too much carbon dioxide (CO₂). Because CO₂ is the "key" that allows oxygen to release from your blood into your muscles and brain, breathing less and breathing more quietly actually leads to better oxygenation.
    \item The BOLT Score is Your Fitness Compass
McKeown introduces the Body Oxygen Level Test (BOLT) as a primary health metric. By measuring how long you can comfortably hold your breath after a normal exhale, you can determine your body’s tolerance to CO₂. A low BOLT score (typically under 20 seconds) indicates poor breathing habits and lower endurance; raising this score through practice is the primary goal of the program for improving health and stamina.
    \item Simulated High-Altitude Training
You don't need to live in the mountains to gain the benefits of altitude. By using specific breath-holding techniques during exercise (creating "air hunger"), you can mimic the effects of high-altitude training. This forces the body to increase its red blood cell count and improve its buffering capacity, allowing athletes to perform at a higher intensity with less breathlessness.
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