RLRH: ​What If Muscle Glycogen Isn’t the Performance Limiter We Think It Is?​


Here’s your free but abridged version of this week’s “Run Long, Run Healthy” newsletter. Subscribe here to receive the full edition with more on the latest scientific articles and research on training, nutrition, shoes, injury prevention, and motivation.


What If Muscle Glycogen Isn’t the Performance Limiter We Think It Is?

For decades, high-carbohydrate diets have been considered the gold standard for fueling endurance activities, largely due to their ability to optimize muscle glycogen stores. But a new study is challenging our understanding of that, and the role of low-carb and high-carb diets (again).


Latest Podcast Episode:
The Key To Running Longevity Is...Ergodicity.

What is ergodicity and how can it help you plan for longevity in your running? That’s the topic my colleague Thomas Watson is exploring in today’s episode, where he looks at how it can apply to single races, seasons, or your whole life - and why you should be more like Haruki Murakami and less like David Goggins.

Or listen and subscribe to the show wherever you get your podcasts:


Is Your Garmin’s VO₂max Estimate Useless?

I’m often asked: “Can I trust the VO₂max score from my GPS watch?”

I don’t ever really have a good answer, other than that lab testing is ideal. Nevertheless, for recreational runners, seeing fitness increases can feel motivating, but for athletes chasing marginal gains, a misleading VO₂max estimate could be more frustrating than helpful.

​A new study put the Garmin Forerunner 245 to the test against the gold standard laboratory treadmill ramp tests with respiratory gas analysis.

Here's what they found.


The Consequences Of Delaying Carbs After Your Run

Most athletes know that carbs are crucial for performance, but what happens when you skip them after a workout?

Recent research suggests that delaying post-exercise carbs could actually impair your recovery and next-day performance, despite the belief that glycogen stores can be replenished later.

Even if you’re not training again the same day, the so-called “anabolic window” might be more important than you think—especially for fast recovery.


The Secret To A Stronger, Faster Marathon:
Negative Splits

Marathon success is rarely about how fast you run the first half of the race, but rather, how you execute the second half (or really, that final 6.2 miles).

One of the most effective ways to make that happen is by using a negative split strategy—running the second half faster than the first.

​A recent mini-review article by Gerasimos Grivas breaks down the science and psychology of negative splits. Here’s what you need to know about how to execute the perfect marathon.


High Mileage, Hidden Risks? The Colon Cancer Debate

Epidemiological studies consistently show that physically active people have a lower cancer incidence, including fewer colon polyps and lower rates of colorectal cancer. But what if there’s a paradox lurking at the extreme end of training?

​A new prospective study (actually an abstract presented at a scientific conference — a key detail) suggests that very high-volume marathon and ultramarathon running may actually increase the risk of advanced precancerous colon lesions.


Thanks for reading. As always—Run Long, Run Healthy

~Brady~

113 Cherry St #92768, Seattle, WA 98104-2205
Unsubscribe · Preferences

Marathon Handbook

Join over 160,000 runners: expert running tips, the latest news, shoe and gear reviews - and the occasional running meme.

Read more from Marathon Handbook

Running News : Training Tips : Training Plans : Shoes+Gear : YouTube : Podcast Hi runners, 👋🏼 Katelyn here with newsletter #669! Happy Thanksgiving! This is the shoe issue — starting with our latest podcast, where we break down the best running shoes of 2025, plus the essential guides you need to make smarter choices for your feet, your training, and your recovery. If you’re thinking about upgrading your shoes (or already grabbed a new pair), today's edition has everything you need to feel...

, Running News : Training Tips : Training Plans : Shoes+Gear : YouTube : Podcast Hi runners, Jessy here with newsletter #668! 🎉 Happy Wednesday! Here's what I have for you today: The 2025 IAU 50km World Championships have been postponed after Delhi officials suspended all sports events amid dangerously high pollution levels. Warm-ups matter more than you think, and most runners are missing the science behind them. Here’s why 15 minutes could make or break your next workout. The Enhanced Games...

Running News : Training Tips : Training Plans : Shoes+Gear : YouTube : Podcast Hi runners, 👋🏼 Katelyn here with newsletter #667! As temperatures shift and the holiday season approaches, we’re bringing you practical guidance to keep your running comfortable, strong, and energized. From knowing exactly how to dress for unpredictable weather, to strengthening a common weak link for runners, to starting Thanksgiving morning feeling your best, today's lineup is all about smart preparation: New...