Some Work, All Play

We campaigned for the Nobel Prize in bodily functions before this great episode! A main topic was a new review study on cross training that found no difference between cross training and running interventions FOR RUNNING PERFORMANCE. That’s wild, and we use the result to zoom out to describe why we think most athletes should be doing some cross training. We also talked about a pair of studies on c...

The 2026 Western States 100 was astonishingly fast and uplifting! It was also astonishingly dramatic. This episode breaks it all down when it’s fresh in our minds. We talked the new course records and what it means to go for it in the modern era (and what it means to go for it in life). Other topics include the “death before DNF” mentality, brand battles, racing trends, and carbs in ultras. We bro...

It’s the best time of the year, and we brought that energy into this great episode! We started by bringing out our big predictions and hot takes for the Western States 100. The hottest take: everything about our understanding of endurance physiology is going to change on Saturday. We tell you why. We also talked about a new study asking a fascinating question: does the intensity of easy training m...

We developed the ultimate AM wake-up hack (which we tell you about in the intro) before this great episode! A main science topic was a new paper on how the temperature in an athlete’s training location influences race performance. It tells a story about heat training generally that everyone needs to pay attention to. And guess what? A new journal article makes yet another argument against higher c...

We removed all the cutlery from our house before this great episode! The main science discussion was on a new study looking at reproducibility of adaptations in individual athletes. The relatively surprising finding is that there was no significant correlation in how the same athlete responds to the same intervention across time. We discuss what that means for training science. The word “holistic”...

We put some cinder blocks under the head of our bed (for science!) before this great episode. A weird study just came out finding that head-up sleeping may increase red blood cell totals. We talk about what it means and what it doesn’t mean. Excuse us while we launch a cinderblock start-up. We also discussed a breakthrough in gene editing for cholesterol, and what that could mean for the future. T...

We basked in some amazing news before this great episode! The main topic was a breakdown of one of the most important elements of performance and health: blood volume.  Studies show that blood volume can seem to act as a synonym for fitness, with one finding that 6 weeks of training gains can be reversed with a phlebotomy that returns blood volume to baseline levels. Positive adaptations can happe...

We talked about some of the strangest and coolest research topics in endurance sports for this episode! Basically, the science discussions went long, so we just ran with it. The main discussion was on how to stop cramps, laying out 10 theories. But put on your tin foil hats, because we think the cramping conspiracy runs deep. Our theory: cramping is connected to fatigue resistance is connected to...

We had some HYPOTHESES for this amazing episode! The main topics all revolved around fatigue resistance (often called “durability” in the literature), which we think is the most exciting area of training theory and physiology. It started with Rachel Entrekin’s legendary overall win at the Cocodona 250, an event that explores some of the strangest and coolest parts of endurance. Our big theory: wha...

We violated the warranty on ankle tape before this great episode! A main topic involved taking a step back to understand the historic context of Vinny Mauri’s 2:05 debut marathon. We think it’s a performance that signals a fundamental shift in the future of the sport for everyone, and we discuss why. We also talked about the exciting news that Jim Walmsley is heading to Western States with a spons...

We made an unfortunate impulse purchase (you'll see) before this great episode! The main topic revolved around the world records at the London Marathon, including Sebastian Sawe’s 1:59:30 winning time. We discuss his mid-race fueling, bicarb use, shoes, and so much more.  Plus, there was an important study measuring the differences in mechanical output between sprints, strides, and plyometrics...

We had just the right amount of Dunkin’ coffee (a barrel) before this great episode! The main topic was everything we learned at the Boston Marathon, highlighted by Jess McClain running 2:20:49 to break the American Course Record by over a minute. We break down our experience the most magical weekend! The most memorable moment for us: Around 30k, Jess fumbled a bottle (with a gel on it) right at t...

We got overconfident with a shoe experiment before this great episode! It started with a discussion of race-day fueling of Tadej Pogacar (who might be the greatest endurance athlete ever). 250 grams of carbs and 1430 calories for breakfast?! We zoom out to talk about cycling fueling generally, along with possible gender differences. Then it was a big science discussion on a new study on heat and a...

We listened to a troubling amount of Noah Kahan music before this great episode! The main topic outlined our theory on using downhill training for strength and speed. The repeated bout effect from downhill-induced eccentric muscle contractions causes rapid improvements in muscular strength and running economy. We think that harnessing those principles is a pathway to fatigue resistance. Did we get...

We imagined doing PG-13 things to a very tasty gel before this great episode! The main training topic was a discussion of steady running. Lots of theory talks about “hard days hard and easy days easy.” But we think there’s a place for an addition: “medium days medium.” We discuss the rationale and timing of how to work steady running into a typical week. We also had a big discussion of pregnancy a...

We put on our spacesuits for this great episode! The main topic was a study finding that just putting a dissolvable carb strip on the tongue could improve performance by 3% in a short time trial. What?! How can carb strips and mouth rinses improve performance? We discuss the weird implications of cephalic-phase responses.  And this one was full of amazing topics! Other topics: our first movie thea...

We wore the best shoe ever before this mailbag episode! We opened it up to listener questions, diving into tons of tricky and fun topics. Topics this week: David’s first run in the shoe that’s changing road running, our eventful weekend, Omega 3 supplementation, the types of heat training we like, our dream study design involving bicarb and fatigue resistance, leptin levels, upper body lifting, im...

We stocked up on neck floaties before this great episode! The main topic was a discussion of the constrained total energy expenditure model, which argues that physical activity will often have a smaller impact on energy expenditure than predicted. We do an interdisciplinary zoom-out to talk about how it relates to the research on low energy availability and within-day deficits. The conclusion: fue...

We're doing our first early-release episode to talk about the shocking ending of the US Half Marathon Championships on Sunday. As Jess McClain was charging to victory, with Emma Grace Hurley and Ednah Kurgat poised to make Team USA with her, all 3 athletes were directed off course by a police escort motorcycle, the official lead vehicle, and a media motorcycle.  The disgrace is what happened n...

We washed all of our bowls THOROUGHLY before this great episode! A main topic was the story of US Ski Mountaineering at the Olympics, where Cam Smith and Anna Gibson had miraculous performances. 50 years from now, people will still be talking about this team with the impossible dream. And this one had extremely interesting science that had us asking lots of big questions. We talked about a study o...

We put our hands down our pants (for warmth) before this amazing episode! The main topic revolved around the Black Canyon 100k, where Jenn Lichter and Hans Troyer set course records, and the ultrarunning took another major leap forward. We discuss what we learned before laying out an overview of our ultra training philosophy. The sport is changing so fast that we’re almost certainly wrong (and bia...

Real talk! This episode is great, but maybe don’t listen out loud IN PUBLIC. The main training topic was a deep dive on long runs. We break down some of the competing long run theories, and how they fit into performance. The discussion ends with 5 principles to know (subject to change as competing theories duel it out). And there were so many amazing topics! Other topics: the Real Talk Express, Me...

We cornered the market on mozzarella sticks before this awesome episode! The main topic involved our recommendations for electrolyte use in races and hard training. Sweat replacement is one of the strangest, least understood parts of athletic physiology. We give our guidelines from lots of real-world experimentation.  And this one was full of incredible topics! Other topics: the happiest place on...

We ordered extra-extra cheese before this deep-dive episode. The main topic took up most of the recording today, involving a new narrative review that argues for a low-carb approach for endurance athletes. The real-world performance benefits of carbs are clear for anyone who has traveled this path, but at the end of the day, who cares? It's just performance. The low-carb believers can get left...

We loaded up on Vitamin D (and deodorant) before this fresh episode! The main topic was a new sodium bicarbonate study, tracking 40k bike time trial performance at altitude. It’s another brick in a really big scientific wall supporting the use of bicarb for performance. We zoom out to let you know why we think it’s also effective even in very long distances... and maybe at lower (cheaper) doses. W...