We're here! It's race week for the Western States 100. This episode talks through how we're feeling before the moonshot. Hopefully there are helpful similarities to all of the big, scary things in your lives! We also break down a new study that feels like the Manhattan Project of sports science, testing "replicability" in the field. You know it's serious when there are 99 authors! It found low replicability rates, particularly related to effect size, with massive implications for how we think ab...
Jun 24, 2025•1 hr 16 min
Our favorite episodes involve answering listener questions in a "no secrets" style. That means we might be right, we might be wrong, but we'll always be honest (and hairy!). We started with a game theory analysis on how we think this year's Western States 100 will play out. This is the type of conversation that athletes have before every race, but they usually wouldn't play it out in public. We can check our work in 2 weeks! And then we broke down tons of great questions! Topics: what drives us,...
Jun 17, 2025•1 hr 49 min
This episode was such a fun mix of science, emotions, and hot tubs that could cook a turkey! We started with some thoughts on Western States, less than 3 weeks out from the race. Does embracing the stage also mean embracing social media posts telling you that you aren’t being picked to perform well? Our argument channeling Tyrese Halliburton of the Indiana Pacers: the “noise” can be performance enhancing if you have fun with it! The main science topic was a WILD study on the hot tub improving he...
Jun 10, 2025•1 hr 42 min
We gulped down some pungent juice before recording this amazing episode! The main topics were the two big pieces of news: Jim Walsmley won't be racing Western States, and Kilian Jornet is making training videos now. Jim is the GOAT and we gave him an 85% chance of winning just last week. He's the supermassive black hole at the center of the Western States galaxy. Without Jim at the start line, how does it change the race? Kilian is the GOAT too (yes, we have a GOAT herd), and he just released a ...
Jun 03, 2025•1 hr 41 min
This episode was a total joy with toe warmers in all the right places (and some of the wrong ones)! The main scientific topic was a new study on how high carb fueling may improve heat adaptation. We broaden that out to a question from a listener on the old "calories-in, calories-out" framework, and why that doesn't apply to athletes from evolutionary or exercise science perspectives. The big takeaway from 2 decades of research: avoiding excessive within-day deficits from training may improve hea...
May 27, 2025•1 hr 47 min
We had a ridiculous amount of fun recording this episode! The main science topic was on a new pre-print study on post-exercise ketones, showing higher carb storage and lower glycemia in athletes taking them. Is it possible that high carb has a special interaction with post-exercise ketones that might be at the heart of recent performances? It's uncertain. We just take them because we like the taste of robot butt. We also had a big breakdown of the cost of high-carb fueling. Megan did calculation...
May 20, 2025•1 hr 47 min
Endurance sports are in the midst of a revolution that will change everything about what we think humans can do. This week at the Quad Rock 50 Mile, we felt it firsthand. David set a 14-minute course record at this classic, steep Colorado race. We break it all down, "no secrets" style. Topics: high-carb fueling, big hydration totals, why heat training might be the next frontier, pre-race meals and supplements, ice bandanas, gut training, downhill running, uphill treadmill, and lots more. No matt...
May 13, 2025•1 hr 44 min
Our favorite episodes are these Q+As where we answer listener questions on all of the hottest topics! It's called a "No Secrets" Q+A because we try to take you behind the curtain, speculating about ideas that might not be talked about in public very often. Let's get spicy! The main topic was Cam Wurf's reported 200 grams of carbs per hour at Ironman Texas to set a bike split record. These extreme carb totals are starting to become more prevalent in triathlon. Do we think they're here to stay? Su...
May 06, 2025•1 hr 45 min
We put on our space cowboy outfits for this great episode! The main topic centered on the almost-ubiquitous use of higher carb intakes in recent races, from the Canyons 100k to the Boston Marathon to the cycling classics. What once seemed optional is now mandatory. Where do the next breakthroughs come from? We outline some ideas to try to catch the waves before they become obvious. There was also some fascinating science on warm-weather and metabolic processes, showing reduced carb oxidation rat...
Apr 29, 2025•1 hr 34 min
Our minds were blown by the Boston Marathon right before recording this great episode! The main topic was a new study on the Puma R3 super-shoe, conducted by a top researcher. It showed a shocking 3% improvement in running economy relative to the previous generation of super-shoes, with a universally positive response among study participants. We discuss the evolution of the tech, how it was made with the help of optimization algorithms, and what might come next. Running may never be the same, a...
Apr 22, 2025•1 hr 44 min
We put sensors in all the right places before this HOT episode! The main discussion was on the emerging science of heat training, centered around a 2025 study that showed 3 x weekly sessions could sustain hematological adaptations from an altitude camp. Heat training is no longer just about being ready for hot weather. It's about helping our blood be full of oxygen, powering performance in all conditions. We try to take a "no secrets" approach to bring you onto the front lines of The Heat Revolu...
Apr 15, 2025•1 hr 40 min
We put on our finest white spandex for this amazing episode! The main topic was a new review study on protein needs for endurance athletes. The authors used a cool method of isotope labeling to argue that endurance athletes need more protein than traditional recommendations. The nutrition revolution is not just about carbs! And this one was full of great topics! Other topics: the announcement of an Unbreakable 2 documentary heading into Western States, Kilian Jornet's sustained dominance since t...
Apr 08, 2025•1 hr 39 min
We pondered the genetics of smelling ants before this great episode! The main topic was a new study that found the brain may use myelin lipids for fuel during low glucose conditions like marathons. This could have massive implications for how we think about fueling and fatigue resistance, including for cognitive function. Our big theory: fueling is just as much about nourishing and protecting the brain as it is the legs. And this one was full of amazing topics! Other topics: the resurrection of ...
Apr 01, 2025•1 hr 29 min
We took off our armor for this incredible episode! The main discussion might have been one of our most important (and fun) ever: the Big Alta 50k DNF, failure, and what it truly means to go for it. David raced Big Alta because it was somewhere that he couldn't hide. We needed to gather data about what happened at the very edge of human capabilities. And when you F around...sometimes you find out. We hope that you feel a connection to your big scary dreams. Thank you for giving us the courage to ...
Mar 25, 2025•1 hr 43 min
We celebrated the 250th recording for this great episode! The main topic was a new study on fatigue resistance. How do you actually improve performance after multiple hours of work? It’s the greatest mystery of endurance, and whoever solves it will have a big advantage. We think that we have some answers for training, fueling, and the nervous system. And this episode was jam-packed with tons of amazing topics and questions! Other topics: race week reflections before the Big Alta 50k, confidence,...
Mar 18, 2025•1 hr 25 min
We lifted some styrofoam plates painted like metal before this great episode! The main topic was a new study showing improved fatigue resistance for athletes doing heavy lifting twice per week. Yes... we regret to inform you that we think you should probably have a squat rack nearby. Prepare your butts. We also answered a question on carb intake after exercise, framed around a pro triathlete recently announcing that they had high hemoglobin A1C. We talk about some of the complications of that pa...
Mar 11, 2025•1 hr 43 min
We brought some very sore legs into this great episode! The main topic was a new study on "Zone 2 Training," which gathered a panel of experts to review what Zone 2 means and why it matters. Our theory is that Zone 2 training is interacting with high-carb fueling to drive some of the performance revolution! We also talked about a new study on heat training. It shows that heat-induced adaptations and fitness improvements seem to mimic one another, but may come from different sources. Thus, stacki...
Mar 04, 2025•1 hr 35 min
We put on some supershoes for an extra boost for this great episode! A main topic was a question we get a lot: whether high-carb fueling during training is healthy in a broader sense. We not only think it's healthy, we think that the question is best asked another way: how much healthier is fueling your training than the alternative of underfueling? It's true that you probably don't want to be slurping a gel at 3 PM for a snack. But around training, try to fuel the work you're doing. The big sci...
Feb 25, 2025•1 hr 40 min
We bought stock in baking soda before this record-breaking episode! It was a "No Secrets" Q+A, where we lay it all on the line. This one was so fun! The first big question was on the deluge of world records set in the last week. Our theory is that compound gains are being harnessed from nutrition, supplements, and shoes that are changing how athletes can train and adapt across all endurance sports. We break down the shifts in training theory, and predict what comes next. Next was a question abou...
Feb 18, 2025•1 hr 35 min
Our minds were blown this weekend as more records were annihilated on the trails (at the Black Canyon 100k) and the track (at the Millrose Games)! We talk about The Performance Revolution: what's causing it, what we all can learn, and what comes next. The future is here. And the future is wildly fast! Next up was a new study on strength training for cyclists! We talked about our evolving feelings on strength training, why we encourage athletes to do squats, and why we think single-leg split squa...
Feb 11, 2025•1 hr 40 min
We embraced the pressure for 2025 before recording this great episode! A concept we disagree with is that "pressure will break down the mind," referring to saying big, scary goals out loud. Our main idea: pressure is a joyful part of sports. We talk about our long journey to get to this point, and why you should want the ball with time running out, your team down by 2, everyone counting on you. Pressure is fun! The big science topic was one of the strangest parts of human physiology: the repeate...
Feb 04, 2025•1 hr 38 min
This episode is one of our all-time favorites, diving into tons of the most important (and most frivolous) topics! As always, it’s in the “no secrets” style, where we lift the curtain and show you what people are thinking at the top end of endurance sports, but might not want to say publicly. Plus, there were so many laughs mixed with serious moments. This one is a JOURNEY. Topics this week: the “Trial by Miles” video, going to dark places in workouts, dealing with brain “panic” when things are ...
Jan 28, 2025•1 hr 37 min
This episode was so fun, and it wasn’t just the cinnamon rolls we used for carb research. The main topic was a new study that took a cool design and extended the conclusions beyond their reach, theorizing that athletes should reconsider high-carb approaches for peak performance. We outline where we think the conclusions missed the mark. It makes us uncomfortable to disagree in this way, but we think it’s important for the health and performance of all athletes. Next, we dove back into our comfor...
Jan 21, 2025•1 hr 37 min
We brought so much gratitude to this amazing episode! The main topic was the news announced this weekend: David's Leadville 100 performance won the International Trail Performance of the Year. Yes, tears were shed. To everyone who listens, THANK YOU. In ways that go deeper than words...thank you. We reflect on the training, the journey, how our lives have changed, and what's ahead. Shooters shoot. Next it was a "No Secrets" Q+A! Topics: why hydration recommendations of "drinking to thirst" are o...
Jan 14, 2025•1 hr 33 min
The best moment of our lives happened last week. It's not the baby. It's a social media mention from the GOAT Kilian Jornet. And we brought that celebration energy to this awesome episode! The main study was on the types of training that leads to faster marathon times, looking at 150,000 datapoints. With findings that overlap with other studies, we can start to outline the most direct way to make running faster (and more fun). The remainder of the episode was in our classic "No Secrets" Q+A styl...
Jan 07, 2025•1 hr 36 min
We got some very surprising news before recording this celebration episode! This one has it all: complicated training questions, predictions for the future, and a stunning twist to start the episode (and we were in for a lot more stunning twists after we recorded). The questions from podcast listeners were on tons of amazing topics: heart rate drift tests to estimate zone 2, how to pace ultras, why we think 2025 will be the year of a hydration emphasis in endurance performance, the sponsorship l...
Dec 31, 2024•1 hr 20 min
We celebrated a wild year with a "No Secrets" Q+A episode! This one is full of fascinating topics, mixing science, theory, and hot takes into the perfect holiday stew. The questions all came from podcast listeners on the following topics: how to think about gut training, Zone 2 heart rate and how terrible some online calculators are for athletes of all levels, our favorite speed workouts to gauge progress over time, incorporating cross training into long-term growth, specific guidelines for cros...
Dec 24, 2024•1 hr 30 min
We bowed down to the power of hot mugwort before this amazing episode! The main topic was on a study that may be the long-lost "missing link" in our training theory. It took 12 elite endurance runners and had them do sprints of 100 meters and 400 meters, along with a VO2 max test. Their findings (and one striking non-finding) may connect studies on speed interventions with real-world implications. We also answered listener questions in the "no secrets" style! The most hairy question was on a top...
Dec 17, 2024•1 hr 39 min
We collected some wonderful questions before this great episode! It's our classic "no secrets" style, where we take you behind the scenes to combine research and theory with what athletes are actually doing, but maybe not talking about. We started with a new study on maintaining heat acclimation, which helps answer questions on how to improve blood volume year-round in a sustainable way. Then it was onto the questions! Topics of the questions: sodium bicarbonate and ketone use, the difference be...
Dec 10, 2024•1 hr 38 min
We got our Rich Roll on before this amazing episode! David's appearance on the Rich Roll Podcast came out this week, and we started with some takeaways from a surreal experience. We then pivot into some talk on protein in adaptation and recovery. When in doubt, the answer for us is often to throw some protein on it. Next was a truly wild study that looked at low energy availability and managed to do the impossible: it included a control group that was blinded to the intervention. How is it even ...
Dec 03, 2024•1 hr 30 min
