Running a marathon is a bad idea—and in this episode, I explain why. I react to a shocking new study suggesting that during a marathon, the brain may actually consume myelin (the fatty insulation around nerve fibers) for fuel once glycogen stores run low.

The researchers reassure us that the brain “bounces back naturally over time.” I’m not so reassured. I talk about the acute damage caused by marathon running—not just to the brain, but also to the heart, kidneys, hormones, immune system, and inflammatory response.

I also go deeper into the long-term concerns around extreme endurance training: the diminishing returns of chronic cardio, why endurance training often fails as a fat-loss strategy, the “struggle and suffer” ethos of the endurance scene, and the opportunity cost of spending all your fitness energy shuffling down the road instead of building strength, power, explosiveness, and resilience. I explain why “what doesn’t kill you makes you stronger” is often misunderstood through the lens of hormesis and cumulative stress load, and finish with my preferred approach to lifelong fitness and longevity: walk more, lift weights regularly, and sprint once in a while.

 

TIMESTAMPS:

Running a marathon is a bad idea. Running those 26 miles can transform your brain. [01:05]

Myelin is the fatty insulation around nerve fibers used as fuel when we run out of glycogen during a marathon. The brain fog one gets is caused by the loss of myelin. [02:24]

Brad is looking at the stress on the brain as a result of metabolic myelin plasticity. [04:35]

Long distance running places significant demands on the body and brain. [07:10]

Numerous critical health immune inflammatory and cardiac biomarkers get temporarily blown off the charts even in the best prepared athletes, but more so in the recreational athletes. [09:45]

If you were to go directly from crossing a marathon finish line to the nearest emergency room and have blood drawn, you would have the same lab results as someone suffering from a myocardial infarction, a heart attack. [10:47]

There's also prominent research revealing how the immune system is suppressed for a significant period after the marathon. [14:15]

The essence of peak performance and achieving bucket list goals is to do them correctly rather than drag a tired, unprepared body to the finish line. [17:58]

One study suggests that conducting around two and half hours a week of endurance exercise comfortably paced is sufficient. [20:07]

There's extensive and mounting research that endurance training simply does not work for fat loss. [22:14]

An overuse injury is an obvious sign that the body is being overwhelmed and the training is not appropriate. [27:38]

The obligate runner is one who has taken to the extremes similar to the anorexic needing control. [29:10]

Effort and struggle are deeply satisfying when you're pursuing peak performance goals with honor and maintaining constant vigilance over your mental and physical health. [31:52]

Putting all that energy to a narrow fitness goal like endurance training, precludes other far more valuable fitness endeavors. [33:53]

Broad-based, full body fitness is the key to general health, vitality and longevity. Endurance competency is a small sliver of the big picture. [35:10]

Shoes enable poorly adapted people to do an activity that they really shouldn't be doing. [37:16]

Running a marathon is such an extreme challenge and it is very difficult to train in an appropriate sensible manner. A low-key casual approach can even lead to excellence in endurance training provided we don't succumb to these crazy influences that turn you into an obligate runner. [39:24]

Is the old saying; What doesn't kill you, makes you stronger." really accurate? [43:47]

You do not have to have sore muscles to grow stronger. Stress and breakdown are a byproduct of something you're doing to try and improve your health [46:27]

You can get a detox effect from fasting but you can also improve your digestive system by just changing your diet. Or you can try a cold plunge. [47:24]

Benefits come from the mechanical load or the cardiovascular load not the damage to the brain you get when you are overdoing it. [50:46]

When thinking of a marathon, think about the pounding of the cement for 26 miles rather than a century bike ride or long distance hiking with low or no impact on your feet. [51:42]

We want to create a fitness program where you spend a lot of energy on resistance training for your muscles and dedicate a portion to explosive efforts. [55:39]

 

LINKS:
Brad Kearns.com
BradNutrition.com - 20% OFF Your First Order!
B.rad Superdrink – Hydrates 28% Faster than Water—Creatine-Charged Hydration for Next-Level Power, Focus, and Recovery
NEW: B.rad Real Rad Gummies - Creatine + Nootropics for Focus, Motivation, Performance, and Recovery!
B.rad Whey Protein Superfuel - The Best Protein on The Planet!
Brad’s Shopping Page
BornToWalkBook.com
B.rad Podcast – All Episodes
Peluva Five-Toe Minimalist Shoes - Save 10%
TED Tallk by James O'Keefe, M.D.
Brad's Podcast with Dr. Joan Ifland
Brad's Podcast with Cynthia Monteleone
Jay Feldman Wellness.com
WHAT RUNNING A MARATHON DOES TO YOUR BRAIN 
Does Marathon Running Harm the Brain? New Study Reveals Surprising Answer!
Cognitive Benefits of Open-Skill Sports in Childhood: Evidence from the ABCD Study 

 

We appreciate all feedback, and questions for Q&A shows, emailed to podcast@bradventures.com. If you have a moment, please share an episode you like with a quick text message, or leave a review on your podcast app. Thank you!

Check out each of these companies because they are absolutely awesome or they wouldn’t occupy this revered space. Seriously, I won’t promote anything that I don't absolutely love and use in daily life:

B.rad Nutrition: Premium quality, all-natural supplements for peak performance, recovery, and longevity; including the world's highest quality whey protein! Get 20% OFF your first order!

Peluva: Comfortable, functional, stylish five-toe minimalist shoe to reawaken optimal foot function. Use code BRADPODCAST for 15% off!

Jaspr Air Scrubber: Ultra high-performance air purifier - blows other air filters away! Save $200 on your unit with code BRAD.

Get Stride: Advanced DNA, methylation profile, microbiome & blood at-home testing. Hit your stride the right way, with cutting-edge technology and customized programming. Save 10% with the code BRAD.

Online educational courses: Numerous great offerings for an immersive home-study educational experience

Primal Fitness Expert Certification: The most comprehensive online course on all aspects of traditional fitness programming and a total immersion fitness lifestyle. Save 25% on tuition with code BRAD!

#bradpodcast

Running a marathon is a bad idea&mdash;and in this episode, I explain why. I react to a shocking new study suggesting that during a marathon, the brain may actually consume myelin (the fatty insulation around nerve fibers) for fuel once glycogen stores run low.
The researchers reassure us that the brain &ldquo;bounces back naturally over time.&rdquo; I&rsquo;m not so reassured. I talk about the acute damage caused by marathon running&mdash;not just to the brain, but also to the heart, kidneys, hormones, immune system, and inflammatory response.
I also go deeper into the long-term concerns around extreme endurance training: the diminishing returns of chronic cardio, why endurance training often fails as a fat-loss strategy, the &ldquo;struggle and suffer&rdquo; ethos of the endurance scene, and the opportunity cost of spending all your fitness energy shuffling down the road instead of building strength, power, explosiveness, and resilience. I explain why &ldquo;what doesn&rsquo;t kill you makes you stronger&rdquo; is often misunderstood through the lens of hormesis and cumulative stress load, and finish with my preferred approach to lifelong fitness and longevity: walk more, lift weights regularly, and sprint once in a while.
&nbsp;
TIMESTAMPS:
Running a marathon is a bad idea. Running those 26 miles can transform your brain. [01:05]
Myelin is the fatty insulation around nerve fibers used as fuel when we run out of glycogen during a marathon. The brain fog one gets is caused by the loss of myelin. [02:24]
Brad is looking at the stress on the brain as a result of metabolic myelin plasticity. [04:35]
Long distance running places significant demands on the body and brain. [07:10]
Numerous critical health immune inflammatory and cardiac biomarkers get temporarily blown off the charts even in the best prepared athletes, but more so in the recreational athletes. [09:45]
If you were to go directly from crossing a marathon finish line to the nearest emergency room and have blood drawn, you would have the same lab results as someone suffering from a myocardial infarction, a heart attack. [10:47]
There's also prominent research revealing how the immune system is suppressed for a significant period after the marathon. [14:15]
The essence of peak performance and achieving bucket list goals is to do them correctly rather than drag a tired, unprepared body to the finish line. [17:58]
One study suggests that conducting around two and half hours a week of endurance exercise comfortably paced is sufficient. [20:07]
There's extensive and mounting research that endurance training simply does not work for fat loss. [22:14]
An overuse injury is an obvious sign that the body is being overwhelmed and the training is not appropriate. [27:38]
The obligate runner is one who has taken to the extremes similar to the anorexic needing control. [29:10]
Effort and struggle are deeply satisfying when you're pursuing peak performance goals with honor and maintaining constant vigilance over your mental and physical health. [31:52]
Putting all that energy to a narrow fitness goal like endurance training, precludes other far more valuable fitness endeavors. [33:53]
Broad-based, full body fitness is the key to general health, vitality and longevity. Endurance competency is a small sliver of the big picture. [35:10]
Shoes enable poorly adapted people to do an activity that they really shouldn't be doing. [37:16]
Running a marathon is such an extreme challenge and it is very difficult to train in an appropriate sensible manner. A low-key casual approach can even lead to excellence in endurance training provided we don't succumb to these crazy influences that turn you into an obligate runner. [39:24]
Is the old saying; What doesn't kill you, makes you stronger." really accurate? [43:47]
You do not have to have sore muscles to grow stronger. Stress and breakdown are a byproduct of something you're doing to try and improve your health [46:27]
You can get a detox effect from fasting but you can also improve your digestive system by just changing your diet. Or you can try a cold plunge. [47:24]
Benefits come from the mechanical load or the cardiovascular load not the damage to the brain you get when you are overdoing it. [50:46]
When thinking of a marathon, think about the pounding of the cement for 26 miles rather than a century bike ride or long distance hiking with low or no impact on your feet. [51:42]
We want to create a fitness program where you spend a lot of energy on resistance training for your muscles and dedicate a portion to explosive efforts. [55:39]
&nbsp;
LINKS:
<ul>
<li><a href="https://bradkearns.com/podcast-index/">Brad Kearns.com</a></li>
<li><a href="http://bradnutrition.com/">BradNutrition.com - 20% OFF Your First Order!</a></li>
<li><a href="https://a.co/d/3pVVl9w">B.rad Superdrink &ndash; Hydrates 28% Faster than Water&mdash;Creatine-Charged Hydration for Next-Level Power, Focus, and Recovery</a></li>
<li><a href="https://a.co/d/00WIESpY">NEW: B.rad Real Rad Gummies - Creatine + Nootropics for Focus, Motivation, Performance, and Recovery!</a><a href="https://a.co/d/00WIESpY"></a></li>
<li><a href="about:blank">B.rad Whey Protein Superfuel - The Best Protein on The Planet!</a></li>
<li><a href="https://bradkearns.com/shop/">Brad&rsquo;s Shopping Page</a></li>
<li><a href="http://borntowalkbook.com/">BornToWalkBook.com</a></li>
<li><a href="https://bradkearns.com/podcast-index/">B.rad Podcast &ndash; All Episodes</a></li>
<li><a href="https://affiliate.peluva.com/BRADPODCAST">Peluva Five-Toe Minimalist Shoes - Save 10%</a><a href="https://www.amazon.com/Atomic-Habits-James-Clear-audiobook/dp/B07RFSSYBH/ref=sr_1_1?crid=1VLB1Y60BIHTW&amp;dib=eyJ2IjoiMSJ9.aVjxsZgNHJ6wfgiZ01PPLMHaPE-CV51Y-37RwPAsVpnrtdk7OiuJytPjHy3Q1apjzelTpiPdOcoDspVmVt_vSarerqI9dzIltEEsGh9wH3mFKLEqbiaae10uhBcxmkpkFzRClV5dXKZiELqcOtYyatqiOybKUk1hVKLB8QG8oJZAJd4Ep7sFQrOKAncjfxJnYbLPdpEsiAEuAfM7c65GUgBRp13bb-G-2gbyhPY3mqo.8YNx5SYnnaNe6PYy-BPwaW8X8GvE4S15c3b_7_wKCSo&amp;dib_tag=se&amp;keywords=atomic+habits+book&amp;qid=1774455802&amp;sprefix=atomic+Habits%2Caps%2C197&amp;sr=8-1"></a></li>
<li><a href="https://www.youtube.com/watch?v=Y6U728AZnV0">TED Tallk by James O'Keefe, M.D.</a></li>
<li><a href="https://bradkearns.com/dr-joan-ifland-overcoming-addiction-to-hyper-palatable-processed-foods/">Brad's Podcast with Dr. Joan Ifland</a></li>
<li><a href="https://bradkearns.com/cynthia-monteleone-the-dangers-of-chronic-endurance-training-and-the-benefits-of-sprinting/">Brad's Podcast with Cynthia Monteleone</a></li>
<li><a href="https://www.jayfeldmanwellness.com/">Jay Feldman Wellness.com</a></li>
<li><a href="https://www.youtube.com/watch?v=g4PdyuaGgFg">WHAT RUNNING A MARATHON DOES TO YOUR BRAIN&nbsp;</a></li>
<li><a href="https://www.youtube.com/watch?v=E-WA_yx91MU">Does Marathon Running Harm the Brain? New Study Reveals Surprising Answer!</a></li>
<li><a href="https://pubmed.ncbi.nlm.nih.gov/39876084/">Cognitive Benefits of Open-Skill Sports in Childhood: Evidence from the ABCD Study </a></li>
</ul>
&nbsp;
We appreciate all feedback, and questions for Q&amp;A shows, emailed to <a href="mailto:getoveryourselfpodcast@gmail.com">podcast@bradventures.com</a>. If you have a moment, please share an episode you like with a quick text message, or leave a review on your podcast app. Thank you!
Check out each of these companies because they are absolutely awesome or they wouldn&rsquo;t occupy this revered space. Seriously, I won&rsquo;t promote anything that I don't absolutely love and use in daily life:
<a href="http://bradnutrition.com/?utm_source=brad-kearns-news.beehiiv.com&amp;utm_medium=referral&amp;utm_campaign=brad-kearns-news-dismantling-the-modern-fitness-lie">B.rad Nutrition:</a> Premium quality, all-natural supplements for peak performance, recovery, and longevity; including the world's highest quality whey protein! Get 20% OFF your first order!
<a href="https://peluva.com/?sscid=91k7_1q58j&amp;utm_source=brad-kearns-news.beehiiv.com&amp;utm_medium=newsletter&amp;utm_campaign=brad-kearns-news-dismantling-the-modern-fitness-lie">Peluva</a>: Comfortable, functional, stylish five-toe minimalist shoe to reawaken optimal foot function. Use code BRADPODCAST for 15% off!
<a href="https://jaspr.co/products/airscrubber?rfsn=8682396.a9fad4">Jaspr Air Scrubber:</a> Ultra high-performance air purifier - blows other air filters away! Save $200 on your unit with code BRAD.
<a href="http://getstride.com" data-saferedirecturl="https://www.google.com/url?q=http://getstride.com&amp;source=gmail&amp;ust=1744479083574000&amp;usg=AOvVaw2M5EotlxxWpksCKN7ZVyMD">Get Stride: </a>Advanced DNA, methylation profile, microbiome &amp; blood at-home testing. Hit your stride the right way, with cutting-edge technology and customized programming. Save 10% with the code BRAD.
<a href="https://bradventures.thinkific.com/collections?utm_source=brad-kearns-news.beehiiv.com&amp;utm_medium=newsletter&amp;utm_campaign=brad-kearns-news-dismantling-the-modern-fitness-lie">Online educational courses:</a>&nbsp;Numerous great offerings for an immersive home-study educational experience
<a href="https://www.primalhealthcoach.com/brad/?utm_source=brad-kearns-news.beehiiv.com&amp;utm_medium=newsletter&amp;utm_campaign=brad-kearns-news-dismantling-the-modern-fitness-lie">Primal Fitness Expert Certification</a>: The most comprehensive online course on all aspects of traditional fitness programming and a total immersion fitness lifestyle. Save 25% on tuition with code BRAD!
#bradpodcast

Join Brad Kearns, New York Times bestselling author, world #1 ranked masters 60+ high jumper, Speedgolf world record holder, and former world #3 ranked pro triathlete, in pursuing peak performance with passion throughout life. Brad delivers an engaging mix of step-by-step education on important health topics like staying fit, strong and powerful as you age; transforming diet to lose body fat and increase energy; sort through hype and misinformation to make simple, sustainable lifestyle changes; and broaden your perspective beyond a fit body to experience happy relationships, nonstop personal growth, and ultimately sail to 100 with a happy, healthy, long life. Let’s explore beyond shortcuts, hacks, and crushing competition to laugh, have fun, appreciate the journey, and not take ourselves too seriously. It’s time to B.rad!

 

Join Brad Kearns, New York Times bestselling author, world #1 ranked masters 60+ high jumper, Speedgolf world record holder, and former world #3 ranked pro triathlete, in pursuing peak performance with passion throughout life. Brad delivers an engaging mix of step-by-step education on important health topics like staying fit, strong and powerful as you age; transforming diet to lose body fat and increase energy; sort through hype and misinformation to make simple, sustainable lifestyle changes; and broaden your perspective beyond a fit body to experience happy relationships, nonstop personal growth, and ultimately sail to 100 with a happy, healthy, long life. Let&rsquo;s explore beyond shortcuts, hacks, and crushing competition to laugh, have fun, appreciate the journey, and not take ourselves too seriously. It&rsquo;s time to B.rad!
&nbsp;

Brad Kearns, NY Times bestselling author and world #1 masters age 60+ high jumper, offers a fun and diverse mix of interviews with leading authors and health experts, and  how-to shows for peak performance, weight loss, personal growth, and longevity