Science Of Ultra | Ultra Marathon And Trail Running Expertise | World Leading Endurance Science And Coaching

Ultra marathon running physiology brought to you by the world’s leading scientists, coaches, and athletes. Science Of Ultra host, Dr. Shawn Bearden, brings you interviews and more to deliver everything you want to know about all facets of training, nutrition, hydration, environment, psychology, gear, and much more. Become your ultra best!
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Science Of Ultra | Ultra Marathon And Trail Running Expertise | World Leading Endurance Science And Coaching



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Now displaying: 2015
Dec 29, 2015

My guest today is Jennifer Pharr Davis. She is an author, speaker, and a National Geographic Adventurer of the Year.

Jennifer is among the most well known of American long distance hikers. She holds the record for the women’s FKT for a thru-hike of the Appalachian trail; a record which was the overall outright record for several years and fell by only 3 hrs 12 minutes in the summer of 2015. She has hiked over 12,000 miles on six different continents, including thru-hikes on the Pacific Crest Trail, the Appalachian Trail (three times), the Colorado Trail, the Long Trail in Vermont, the Bibbulmun Track in Australia, and numerous trails in Europe and South America, including the Tour du Mont Blanc, which ultra marathon runners will be familiar with.

Connect with Jennifer:
1) On the trail!
2) Facebook: Jennifer Pharr Davis
3) Twitter and Instagram: JenPharrDavis
4) Her company:
5) Books: Becoming Odyssa and Called Again: A Story of Love and Triumph

She answered many questions on this in depth interview, including:

You hiked that AT in 2005, 2008, and the overall record setting year 2011. Your first women’s record of the trail in 2008 was a bit over 57 days; in 2011 you destroyed that record and did the trail in a bit over 46 days. How did that enormous improvement come about?

Would you describe the demands of a long-distance thru-hike? Granted that weather can have a big impact, what does a ‘typical’ day look like for a long distance thru hiker?

Are you ever running/jogging during a thru-hike or is it all hiking?

Tell us about your training for a thru-hike. In your experience, would a 3-4+ week thru-hike be good training for ultra marathons of 100 miles or longer?

How do you handle sleep deprivation, or functioning on little sleep, for weeks on end? Tell us about your nutrition for a thru-hike.

Tell us about your foot care on a thru-hike.

You wrote an article recently for the New York Times for which you explored the topic of sex differences, or lack thereof, in ultra distance events. Tell us about that.

Tell us about the psychological demands of a major thru-hike.

As an exceptional, experienced, and accomplished ultra-endurance athlete, you have surely had some very dark moments (mentally).
Would you take us to back to your darkest experience, tell us that story and how you handled it?

We wrapped up with some advice for ultra marathon runners interested in tackling a thru-hike.

Dec 22, 2015
My guest today is Patrick Wilson, PhD and RD. He is Assistant Professor of exercise science in the Human Movement Sciences Department at Old Dominion University, in Norfolk, VA, where he also directs the Human Performance Laboratory. He earned a Ph.D. in Kinesiology from the University of Minnesota, where he also received training in the areas of public health and epidemiology. He completed his post-doctoral research training at the Nebraska Athletic Performance Laboratory, specializing in sport nutrition applications for collegiate athletes. And, he is also credentialed as a registered dietitian. 
He has authored numerous peer-reviewed publications covering a wide variety of sport nutrition-related topics. He has conducted both laboratory- and field-based research examining the effects of nutrition on endurance exercise performance, including the effects of carbohydrate composition on gastrointestinal distress and performance during prolonged running. His studies have included marathon runners, ultra-endurance runners, and Ironman competitors.
In this episode, we cover all the angles on gastrointestinal (GI) distress as it applies to ultra runners. You learn the major factors that influence GI distress and how to maximize your chances of keeping your GI tract happy.
In the wrap-up, he answers two key questions.
1. What is the biggest mistake athletes make regarding food/drink intake and GI distress?
2. What take-home recommendation would you give for athletes to reduce their chances of developing GI distress in ultra events?
Dec 15, 2015

William is a 62 year old British and Scottish international athlete and has set 160 ultra distance running records (from 30 miles on the track to 3100 miles/ 5000 kms on the road) at World, British and Scottish level including age-group records.

Connect with William:;  Twitter: @williamsichel;  Facebook:

Since 1994 William has competed in 92 ultra marathons at home and abroad – winning 16 of them. He has also represented Great Britain 11 times and Scotland 7 times.

William has three grandchildren and has been self-employed all his life.

Since 1982 William has lived in the remote Orkney Islands, off the north coast of Scotland, 750 miles north of London.

In this episode we learn all about the training William follows to compete and succeed in extreme ultra endurance events.

Dec 8, 2015
My guest today is…you…and…me.
This episode is all about an amazing new project I’ve created for you. If you don’t want to hear about a new project I have for you, and only what the science on Science Of Ultra - then I’ll be back next week with another amazing Science Of Ultra episode. But, if you want more from me...
Have you ever wondered what it’s really like to have a coach for your ultra training? Is a coach worth the cost? Maybe you have a coach and you wonder how another coach is different. Will a coach really help you to become your best? What are the conversations with a coach like? How exactly does the relationship with a coach work? What sorts of workouts are prescribed? How will I feel following someone else’s prescribed plan every day? How flexible is a coach when life events happen? 
Wouldn’t it be great if you could have the ultimate observer’s experience…to listen to every word between a motivated athlete and a highly qualified coach…to have access to every detail of every workout (even nutrition)…to follow the athletes daily experience…to even be able to ask the athlete questions…the ultimate observer’s experience as if you were there with the athlete for every single step - a completely open book? Wouldn’t that be amazing? Would you like 100% access to follow the journey with an ultra athlete and coach?
That’s exactly what I’m bringing to you now. I’m calling it the Journey to 100. I’ve hired a coach and I’m going to make every aspect of my journey completely open to you, and you can ask me all the questions you like. For the next year, my coach is going to push me towards my first 100 mile race.
This opportunity for you is unprecedented. Never before has there been a completely open, 100% access experience to an ultra athlete’s journey to taking on their first 100 mile race. Nothing like this, with such total access, has ever been done and I’m bringing it to you.
I started Science Of Ultra with a single-minded focus - to connect you with the reliable, valid, and actionable evidence-based knowledge you need to make the most informed choices about your ultra pursuits. I hope that Science Of Ultra is proving to be valuable to you. I absolutely love bringing it to you.
I am now starting a second podcast. The Journey to 100 podcast will be published weekly, just like Science Of Ultra.
However, the Journey to 100 will be focused on giving you what we might call the ‘fly on the wall’ experience. You will be able to listen to my weekly recorded conversations with my coach, you’ll be able to read every workout on the web site, you’ll be able to investigate my nutrition, and you will get my blog posts about my personal experience. In addition, you will be able to ask me questions that I will answer in every podcast episode of Journey to 100. Science Of Ultra will always be exactly what it has been and we have more great science coming in next week’s episode. But, I am using this one episode of Science Of Ultra to let you know about the Journey to 100 because I want you, the loyal Ultra Clan, to be the first to hear about this exciting venture. 
So, how will this work. Well, keep listening to Science Of Ultra episodes every week...
Then join the Journey to 100. While you are on the web site, look at the navigation choices in the top menu. You will find a link to Journey to 100. Click on that menu item link. On the Journey to 100 page, you’ll find all the information you need to join the journey.
Have you ever wondered what the coaching experience is like? Are you interested in what it takes to step up to the 100 mile distance? Maybe you want to become a better 100 mile runner? Maybe you’re just curious. The Journey to 100 is for you! Go to and select Journey to 100 in the menu or go directly to it at
Although Journey to 100 will have it’s own podcast, separate from the Science Of Ultra podcast, I will use the same Twitter, Instagram, and Facebook pages to post for both. So, if you are already following, great! If not, go to and click on the respective follow icons at the top of the page.
When will you ever get to be completely on the inside of a coaching journey focused on a 100 mile ultra race? This is your chance to experience every aspect. Go to (or use the menu link at the top of the main page) to join your Journey to 100.
Dec 1, 2015
Science of Ultra   Episode 13   Carbohydrates for ultra marathon training and racing
My guest today is Asker Jeukendrup, PhD. He is a leading sports nutritionist and exercise physiologist who spent most of his career at the University of Birmingham (UK), where he was a Professor of Exercise Metabolism and Director of Research. He worked the last 4 years for PepsiCo as Global Senior Director of the Gatorade Sports Science Institute Based in Barrington IL (US). He is currently running a consulting business “Mysportscience” and is a visiting professor at Loughborough University. During his career he authored over 200 research papers and book chapters, many of which have helped to change the sports nutrition landscape. He is also the author of 8 books. He is the former editor of the European Journal of Sport Science and Associate editor of the Journal of Sports Sciences. During his career he worked with many elite athletes and teams including several World and Olympic champions. He also practices what he preaches and is competing in Ironman distance triathlons as well as other endurance events. To date he has completed 21 Ironman races including 6 times at the Ironman world Championship in Hawaii. 
You can connect with Dr. Jeukendrup:
Twitter @jeukendrup
Here are some of the questions Dr. Jeukendrup answers:
  1. On a daily basis, what are the carbohydrate needs of an ultra endurance athlete?
  2. How many calories can most people digest and absorb per hour when running?
  3. What is the fate of consumed carbohydrate relative to stores while exercising?
  4. What are the key factors to be considered with respect to the carbohydrates during a long event that may last 24 hrs?
  5. Can we predict when relative glycogen depletion might occur in an ultra marathon?
  6. What should we consider when we are choosing specific high-carbohydrate foods?
  7. What are the key issues to consider relative to the timing of carbohydrate intake prior to, during, and following training workouts?
  8. What about timing of carbohydrate consumption for a race event?
  9. Is glycemic index of a given food different when running vs at rest?
  10. For those who don’t like sweet tastes while exercising or late in races, what are the sources of simple carbs that don’t taste sweet?
  11. Are there data, or any good reason to expect, that any aspect of carbohydrate digestion/optimal sources/etc. will change over the course of an ultra marathon? Does carbohydrate physiology change when we go way beyond the better understood distance of marathon? 
  12. Is consumption of foods that contain protein, fat, or fiber a concern in light of effects on gastric emptying?
  13. When we consume carbohydrate during a run but prior to reaching very low levels of glycogen in muscle and liver, are those calories used more/less/equally to stored muscle glycogen?
  14. Can carbohydrate consumption keep us from reaching a muscle and/or liver glycogen depleted state?
  15. What is the relation between carbohydrates (type, source, complexity?) and likelihood of GI distress?
  16. Tell us about the topic of ‘fat adaptation’ to spare glycogen. From my reading and understanding, there is no good evidence that fat adaptation provides any benefit to endurance performance and it may even impair higher intensity performance (like going uphill) by not ‘sparing’ glycogen but rather by ‘impairing’ glycogen utilization…that apparent sparing may actually be a side effect of impaired utilization.
  17. How does caffeine ingestion interact with endogenous and exogenous substrate utilization?
  18. GI distress late in a race makes it difficult for some people to retain any calories they might swallow. Tell us about this interesting topic of ‘mouth sensing’ and what it might do for us in that situation.
We wrap up with a couple of focused action items:
1) What are the 2-3 biggest mistakes or misconceptions that you see endurance athletes make regarding carbohydrate and fueling for performance? 
2) What advice do you have for runners wanting to dial in their carbohydrate strategies (maximizing calories, best sources for them, etc.) for training and racing? 
Nov 24, 2015

My guest today is Cody Lind. He's sponsored by Scott and, at age 20, is a rising start in the ultra marathon community. He set five course records and placed second in the U.S. Sky Running Series.

We talk about his training, racing, and his perspectives on running. From big weekly mileage to big weekly vertical, Cody trains hard. Learn about his special connection to the Western States 100 mile Endurance Run and what it takes for even a gifted runner to do well in Sky Running in the U.S.

Nov 17, 2015
My guest today is Stuart Phillips, Ph.D. He obtained his Ph.D. from the University of Waterloo in Human Physiology. He joined McMaster University in 1999 as an Assistant Professor and is currently a full Professor in the Department of Kinesiology and Medicine. He is also the inaugural Director of the McMaster Centre for Nutrition, Exercise, and Health Research. His research is focused on the impact of nutrition and exercise on human protein turnover, specifically in muscle. He is also interested in how exercise and protein impact body composition, strength, and function in aging. His research is funded by the Canadian Institutes for Health Research, the National Science and Engineering Council of Canada, the US Department of Agriculture, and the Canadian Foundation for Innovation. He has authored more than 190 research papers and several newspaper and magazine articles.
In this episode, we learn:
  1. What are the overall (daily) protein needs of endurance athletes, and will this differ for ultra marathon runners?
  2. Does it matter if we get it throughout the day vs mostly at one or two meals?
  3. Does our daily average need to be daily or can it average over days?  
  4. Is there a protein hunger, per se, that is reliable and will we self regulate sufficiently?
  5. What is protein used for in an endurance athlete? How much protein is used for energy /ATP?
  6. What do we know, or can we expect about protein needs and use during and following an ultra?
  7. Is protein immediately before, during, or immediately after training handled differently?
  8. Is it beneficial to consume protein immediately after a training bout?
  9. Are there adverse effects of excess protein?
  10. Are all proteins equal?
And, as always, we what up with an advice question:
  • What advice might he give to an ultra marathon runner concerned with their protein intake?
Nov 10, 2015
It is defensible to say that no molecule has as much controversy and misunderstanding in all of exercise physiology and sports than lactate.
We start with the basics:
  1. Where do lactate and lactic acid come from - how is it produced?
  2. What happens to lactate / lactic acid once it is produced - what is it’s fate?
  3. We go through some common statements and talk about what’s correct and what is not:
    • "Lactic acid build up is what causes muscle burn."
    • "Lactic acid stays in muscle and causes soreness."
    • "Doing some sort of stretching, massage, or exercise will ‘wash out’ lactic acid from a prior training session."
    • "Now the big one: lactic acid build up causes fatigue."
  4. The ‘lactate threshold’ has had many definitions. These are as disparate as the onset of blood lactic acidosis to the maximal lactate steady state - very different exercise intensities with regard to endurance performance. Dr. Gladden gives us a brief history and explanation.
  5. Gas exchange is a different topic but many attempts have been made to correlate gas exchange thresholds with lactate thresholds and, ultimately, performance capacity thresholds. This is a big topic area, but Dr. Gladden briefly relates gas exchange concepts/thresholds to definitions of lactate thresholds.
  6. We learn the answer to: Is it necessary to exercise at or above the lactate threshold (whichever definition one uses) to increase it or can sub-LT exercise improve the LT?
  7. There is controversy over the source of H+ (hydrogen ions; protons) in exercise ‘acidosis’. Does it come from lactic acid, splitting of ATP, or some other source?
  8. While the maximal lactate steady state is at least a rough idea of the work load that can be sustained for a ‘long time’, ultra marathons last 4-5 hours on the short side and 24-36 hours in the longer events. How long can the workload of MLSS really be sustained even if every other aspect of performance (hydration, core temp, etc.) could be maintained perfectly?
  9. If lactate / lactic acid doesn’t cause fatigue and the MLSS is not sustainable for ultra marathon distances, to what extent is lactate / lactic acid relevant for ultra marathon training or performance?
We wrap up with two questions as take-home points:
1. What is the biggest misunderstanding that endurance athletes have about lactate / lactic acid? And, what is correct?
2. What advice does Dr. Gladden give to an ultra marathon athlete interested in their LT to apply to their training for ultra marathons?
Nov 3, 2015
My guest today is Luke Nelson. This episode was recorded on location at the Pocatello Running Co. in Pocatello, Idaho, USA. Luke is the race director for the Scout Mountain Ultra Trail race in Pocatello (held in early June each year). He is a Physician Assistant with a full time job. He is the 2012 US Ski Mountaineering Champion. He won El Vaquero Loco seven years in a row and he is a winner of the Big Horn 100. He’s an Ambassador for La Sportive, Patagonia, and Ultraspire. He’s sponsored by First Endurance and Smith.
Luke tells us all about his training, his experiences over the past year, his approach and experience to the mental side of our sport, and what 2016 has in store. He is a phenomenal athlete and an exceptionally kind and generous person, committed to promoting and preserving wild places. You’re going to love this episode.
Oct 27, 2015
My guest today is Jason Koop
  • Director of coaching for Carmichael Training Systems
  • His list of athletes includes some of the biggest names in ultra running but also people like you and me.
  • And, as an accomplished ultra runner himself, he knows first hand all that goes into performing in our sport.
Jason Koop is back…and he answers some very direct questions, like:
  1. In our last episode with Jason, episode 3, he explained his overall approach to training as transitioning from the least race-specific workouts to the most race-specific. A listener might question then, what is the reason for training short interval high intensity far out from a race at all? How does THAT benefit the overall plan and training?
  2. There are proponents of always training below LT, basically training at race pace or lower year 'round. What are Jason's thoughts on that and what are the physiological mistakes in that approach? 
  3. In the fall, many people are thinking about planning the following year. What should we consider as we question which races we sign up for, especially considering necessary recover time between races?
  4. How does he monitor athletes for signs of over-fatigue on a short time frame and over the course of a season?
  5. What is the physiological basis for doing recovery runs (rather than just taking the day off), and how should recovery runs be implemented in the course of a weekly plan?
  6. How does Jason monitor for progress and improvements during a training plan and how does he know it’s time to move on to the next phase of training?
  7. How long is the final phase (‘aerobic’) of training, optimally?
  8. In that final phase, where we are most race specific, what would we expect to be a weekly volume (distance or time) relative to the goal race and how should that volume be distributed throughout a week?
  9. Physiologically, why not divide the desired weekly volume evenly over 6 days, with one day off…what is the distinct benefit of more and less on different days in this final phase?
  10. The big race is now a few weeks away. How do we balance loss of preparedness from tapering with race readiness - what is an effective tapering strategy for shorter ultras like 50k to longer events, like 100 miler?
Plus, Jason answers two  high impact questions…are you ready?
  1. What are the 2 most common mistakes that you see in athletes prior training when they first hire you?
  2. What are the 3-4 key action items that we can put into practice right away to improve our training?
Oct 20, 2015
My guests today are veterans of Science of Ultra; they joined me in Episode 4.LISTEN TO THAT EPISODE (#4) FIRST IF YOU HAVEN’T ALREADY. Today we continue our series with them on all things sweating, hydration, electrolytes, and fluid balance. 
Up first is Team Leader of the Thermal and Mountain Medicine Division at the US. Army Research Institute of Environmental Medicine (aka USARIEM). In addition to his doctorate in exercise physiology, he is also a registered dietician. My first guest is Dr. Sam Cheuvront. My second guest is Principal Investigator in the Thermal and Mountain Medicine Division at USARIEM. He served as the president of the New England Chapter of the American College of Sports Medicine. And, he is an ultra marathon runner himself. So, he knows first hand what it takes to achieve in our sport. My second guest is Dr. Robert Kenefick. Collectively, my guests have published over 200 peer-reviewed papers, book chapters, and reviews. They are two of the world’s leading scientists in hydration and fluid homeostasis, especially during exercise. 
They work for the U.S. Army. So, we must provide the disclaimer that "The views and/or opinions of Dr.'s Kenefick and Cheuvront are theirs personally and do not reflect the views or opinions of the U.S. Army or DoD."
In the first part of this series, episode 4, we focused on the physiology of fluid and electrolyte balance. That episode is packed with fundamental physiology and what we talk about in this episode builds on what we covered in episode 4. So, you’ll benefit most from this episode if you’ve listened to that episode.
Quick background: We sweat to put water on the surface of our skin, which evaporates to the environment. The transition from liquid to gas requires a large amount of energy; sweating cools us because that energy comes in the form of heat, which is drawn from our skin. Sweat that drips off of us, does not provide that cooling benefit. Either way, that fluid loss eventually impacts all three body fluid compartments, which are 1) blood plasma, 2) intracellular (inside cells), and 3) interstitial (outside cells but not including blood).
Listen and learn the answers to these questions:
  1. We start with a scenario: I go for a long run and during the run my urine is dark; after the run I try to replace fluids by drinking plenty the rest of the day and by bedtime, my urine is a much lighter color. But, when I wake up in the morning, it’s dark again…what’s going on?
  2. What is the time-frame for fluid/electrolyte shifts among body compartments?
  3. As we sweat, the fluid and electrolytes initially come from the interstitial compartment, specifically around the glands near the surface of our skin. As we run and sweat…what do we know about fluid shifts and electrolyte shifts across the three body compartments during prolonged exercise.
  4. Another example, I run and take water = regular urination and clear; drink electrolyte solution = less urination and darker…we talked about the physiology of this in episode 4 but now, putting a real world example to the physiology, what’s happening to me in those cases?
Then we move into specific preparation for performance
Dr. Kenefick is an ultra runner and a leading expert on this topic, plus he has access to all resources for measurement and testing. He must never have any problem with fluid and hydration...right?
  1. Once in a while, we hear advocates of ‘bonk’ runs where one would purposefully dehydrate or go out without water. Clearly, this can be very very dangerous and we recommend against doing bonk runs. Out of curiosity, thought, is there any evidence that we can train in a way that will help us to perform better in a dehydrated or low volume state?
  2. Keeping ALL ELSE EQUAL, what are the practical, relative effects of each of the following on sweating: long clothing vs short vs nothing (same material - just different coverage), tightness of clothing, type of material, color of material?
  3. What are the definitions of adaptation, acclimation, acclimatization?
  4. What does it mean to be acclimatized to a hot environment with respect to body fluids, hydration, and sweating?
  5. What are best practices for preparing to race in warmer environments? Exercise, sauna,…?
  6. What is the recommended protocol for acclimation to heat in preparation for an event?
  7. What is the time-course of gain and loss of heat acclimation?
  8. When we plan for thermal stress from the environment, we must consider not only temperature but other factors such as wind, sun exposure, and humidity. Let’s say that we have gone through the acclimation protocol. Is there a cut off temperature/thermal stress range, below which, there is no benefit to performance. How can we gauge whether going through the protocol will be of benefit?
  9. Specifically thinking about what’s going on during running: at what body temperature do we begin to sweat and where on the body do we sweat first, most, etc.?
  10. Should we be concerned about gear placement (e.g., hydration pack vs waste belt) with regard to efficient sweating and cooling? E.g., would we expect any appreciable difference in fluid loss or cooling over time for someone wearing a hydration pack vs waist belt vs none or handheld bottles.
  11. To what extent does carrying extra weight affect sweat loss due to the extra work of carrying it; e.g., as much as 5 lbs for some full hydration packs vs 1 lb or so for a full handheld. 
Many people have the idea that, while running, ‘if they are continuing to urinate and it isn’t very dark, then they are probably OK’. We’ve established that watching urine color - DURING exercise - is not a reliable method for monitoring hydration status. So, “How can I monitor myself for appropriate fluid replacement and maintenance during an ultra marathon (or during a long training)?”   
Our wrap up, big money question today...WHAT’S THE ANSWER?
Oct 13, 2015
My guest today is Scott Trappe, PhD
Dr. Trappe is the Director of the Human Performance Laboratory and John and Janice Fisher Endowed Chair in Exercise Science at Ball State University. He received his undergraduate training at the University of Northern Iowa where he was captain of the swim team. He worked for US Swimming at the Olympic Training Center in Colorado Springs while obtaining his  M.S. at the University of Colorado. His PhD training was with Dr. David Costill at Ball State University followed by post-doctoral training in muscle physiology with Dr. Robert Fitts at Marquette University. For the past 20 years, he has been working with NASA to help optimize the exercise prescription for astronauts.  His work has also been supported by the NIH. Concurrent to the work with NASA, he’s conducted exercise training studies in older adults, aging athletes and various college and elite athletes. Using a whole body to gene approach, he and his colleagues have gained a better understanding of muscle plasticity. He is an expert in the area of adaptations to training and to disuse - or detraining. And, he joins us today to talk about that plasticity, specifically in the area of balancing training with detraining as it may apply to tapering.
In today’s episode Dr. Trappe and I talk about training adaptations, then detraining, then put those together to come to some conclusions about the tapering period where we try to balance these.
The questions I posed to Dr. Trappe include:
  1. Genetics. There was a belief that genetics provide each person with a particular range of possibility and that there is a limit set by those genetics for each person such that one person’s maximal potential may be below another’s lower spectrum. Is that correct and to what degree do genetics compare with training for our endurance capacity.
  2. What is the time-course for the various adaptations: capillarity, mitochondrial capacity, power, neuromuscular control, etc.? [for clarity, capillarity is the density of capillary blood vessels within skeletal muscle - which is important for oxygen and nutrient delivery ; mitochondrial capacity is the sum of the tools a cell uses for generating ATP while utilizing oxygen] - it will vary based on the volume and intensity but we talk generally about the components.
  3. What components continue to develop over years of training and what components of adaptation to endurance are maximized, if any, relatively early (like in the first year or so of regular serious training) - e.g., we don’t continue increasing capillarity indefinitely.
  4. Training prescriptions are often designed so that a given hard day of training is maximized while still low enough in density so that the next training day (perhaps 2 days later) can be completed with equivalent volume/intensity. How do we optimize this - there is a spectrum - steady runs every day vs very hard one day that takes many days to recover from…how do we plan for the balance so that we are making the fastest, steady gains in endurance capacity?
  5. Some prescription plans cycle three weeks increasing in density (volume or intensity or combination), then back off for a week, then start over with a little increase. Graphically this might look like three steps up and one down, repeat. How does this approach compare to backing off slightly in those three weeks and not stepping down in the fourth week - evening out the 4 weeks so that there is a persistent increase in training density over time. Any benefit of one approach over the other?
  6. Cross-training: physiologically useful or can we get more out of staying 100% sport specific and tailoring the workouts carefully (to avoid injury and boredom)?
  7. When we evaluate training, the goal is to maximize adaptable stimulus and provide sufficient environment for adaptation. To what extent do easy days (recovery runs) layer onto the stimulus for adaptation: is there a stoking effect that keeps the stimulus maintained until the next tough workout OR do recovery runs somehow promote a more beneficial adaptation environment - where do recovery runs sit in the balance equation of stimulate/adapt? …what do we know about the specific mechanisms of the benefits of easy days (recovery runs) between hard workouts?
  1. For an endurance runner with capacity X or Y, what is the minimum stimulus required to maintain what they’ve developed; surely this varies for the different components from neuromuscular coordination and control, through muscle bioenergetics…but what do we know about maintaining capacity?
  2. Trail running, and many or most ultra marathons are on trails, require both endurance and an endurance in power - due to the elevation changes, both up and down hills. Are these capacities different from a muscle tissue perspective…flat ground endurance vs mountain hills endurance? Do those capacities detrain differently?
Balancing Training Adaptation with Detraining
  1. Promoting recovery while resisting losses is the fundamental issue at play in the period called tapering. Whatever you call it, it is the final days or maybe weeks as we approach a key race or event. What are the best practices for tapering for endurance events - what works, what doesn’t?
  2. Recovery required from races - 50k-100mile+ all can take a substantial toll on muscle tissue both structurally and functionally. When muscle is trashed - not a lot has been studied in the specific context of ultra marathons but we do know about repeated eccentric loading [eccentric is contraction while a muscle is lengthening - as is required of the quadriceps while running downhill] - what elements of muscle function recover the fastest and what takes the longest to recover?
  3. Considerations for races in quick succession (e.g., 100k-100mile 4-6 weeks apart, or 50k 2-3 weeks apart)?
We wrap up with two specific questions:
  1. What are the biggest mistakes that Dr. Trappe sees distance runners make in their tapering plans?
  2. What three key messages of advice does Dr. Trappe have for ultra marathon runners with regard to tapering?
Should ultra runners use standup desks at work?
Oct 6, 2015
My guest today Ian Sharman
He is part of a small group in the ultra community - he is both a successful coach with his own coaching company and he’s an elite ultra marathon runner. In 2013 he set the record holder for the fastest Grand Slam of Ultra Running. Since Jan 2014 he has won 6 ultra marathons. AND, he has also earned a top-10 finish all 6 times he has run the Western States 100. So far, in 2015, he has won both Rocky Racoon (which he also won in 2011) and the Leadville 100 (which he also won in 2013). 
I dig into Ian’s approaches and philosophies in coaching to learn:
  1. About his current athlete load and how he trains.
  2. His overall framework of training prescription - the macro-view (philosophy) to training for ultra marathons.
He also answers questions like:
  1. How and when, in a season, do you focus on long runs?
  2. How and when, in a season, do you prescribe high intensity workouts - what is the benefit relative to ultra performance?
  3. When, if ever, is cross training appropriate? What’s the benefit?
  4. There are many terms for training features, like ‘speed work’, tempo, striders, fartleks, 2 per day, back-to-back, etc. Do these play a roll in your training prescriptions - how/why/why not?
  5. What might a week of training look like 10 months from a key event (e.g., Leadville 100) vs 1 month out?
  6. Do you use a HR monitor with your athletes?
  7. What is your approach to monitoring or ensuring that training is balanced with the right amount of recovery; monitoring for over-fatigue or over-training? Recovery runs vs days off?
  8. Tapering; how do you approach tapering with your athletes?
We wrap up with two specific questions for the Ultra Clan
  1. What are the two most common mistakes that Ian sees in prior training plans when an athlete first comes to hire him as a coach?
  2. What three specific action items of advice would he give to us that we can make sure we have in place to optimize our training or racing today?
Sep 29, 2015

My guests today are Dr. Sam Cheuvront and Dr. Robert Kenefick

  • Two of the world’s leading scientists in hydration and fluid homeostasis
  • Going in alphabetical order, 
    1. My first guest is Research Physiologist and Team Leader of the Thermal and Mountain Medicine Division at the US. Army Research Institute of Environmental Medicine (also known as USARIEM). His research includes the study of environmental and nutritional factors influencing human work performance. He is a leader in the fields of human fluid needs, dehydration assessment, heat stress mitigation, and exercise thermoregulation. He’s published over 100 -peer-reviewed papers and book chapters. Our first guest is Sam Cheuvront, PhD, RD
    2. My second guest is Principal Investigator in the Thermal and Mountain Medicine Division at USARIEM. He has published over 90 peer-reviewed manuscripts, book chapters AND reviews on fluid homeostasis and the physiological responses to environmental stress. He served as the president of the New England Chapter of the American College of Sports Medicine and received their Honor Award in 2012. He is also part of the Ultra Clan as an ultra marathon runner himself. Our second guest is Robert Kenefick, PhD.

My guests work for the U.S. Army. So, we must provide the disclaimer that "The views and/or opinions of Dr.'s Kenefick and Cheuvront are theirs personally and do not reflect the views or opinions of the U.S. Army or DoD."


This episode is the first in a two part series on fluids, hydration, and electrolyte physiology pertaining to ultra marathon running. We’re starting with the basics and progressing to specific application.

In this episode, you'll learn the answers to:

  1. What are the major body fluid and compartments and definitions the major relevant terms (de/eu/hyperhydration, hyper/hypovolemia)?
  2. What are the mechanisms/routes and quantities of water loss?
  3. How much water does a person need each day?
  4. Drinking to thirst - is it sufficient, like you hear commonly? (spoiler: NO!)
  5. How much salt is lost in sweat - only sodium? To what extent does this change throughout the time-course of an ultra marathon?
  6. What’s in sweat and what are ranges of rates and composition in running?
  7. During exercise, the majority of water gained is in the form of what we drink. But we have heard about getting water also from the breakdown of stored glycogen. Is this accurate?
  8. How can we expand our plasma volume?
  9. When do we need (and not need) an electrolyte-containing drink either during or after exercise?
  10. What is needed in an electrolyte drink beyond sodium?
  11. Hyponatremia; should it be a concern for most ultra marathon runners? 
  12. When does a runner need to consciously add sodium, beyond just following cravings?



Sep 24, 2015
My guest today is Jason Koop
  • Director of coaching for Carmichael Training Systems
  • He’s training everyone from the most famous in ultra running to people in your neighborhood
  • And…he’s an accomplished ultra runner himself…among many others, his finishing list includes Wasatch, Western States, Leadville, and Badwater.
In this episode we learn about
  1. Jason’s overall framework of prescriptions which emphasizes a progression from least event specific to most specific
  2. The optimal time frame to implement a full program
  3. Intervals to raise VO2max
  4. Setting pace and effort
  5. Total interval time of work for raising VO2max and for improving midrange performance
  6. Three broad phases of training and how much work/effort for workouts in those phases
  7. How many workouts per week?
  8. Factoring terrain (and elevation gain) to the workouts
  9. Does Koop use heart rate monitors?
  10. Detraining of VO2max closer to event with Koop’s approach?
  11. Approaches to choosing the number and spacing of races.
  12. Overtraining; over-fatigued/under-rested 
Plus, Jason gives you four pieces of advice that you can implement TODAY to improve your training and racing!
Sep 24, 2015
My guest today is Marty Hoffman, M.D.
  • Chief of Physical Medicine and Rehabilitation, VA Northern California Health Care System
  • Professor of Physical Medicine and Rehabilitation, University of California Davis
  • Research Director, Western States Endurance Run
  • Chief Medical Officer, Ultra Medical Team
  • Serves on several editorial boards, and is Editor-in-Chief, Wilderness & Environmental Medicine
  • Has published well over 100 peer reviewed research studies and 11 books or book chapters.
  • He is an accomplished ultra runner himself - He’s the 2008 Grand Master (50-59 age group) National Champion, USATF 100 Mile Trail Championship, Tahoe Rim Trail
In today’s episode:
  1. All about the history and current topics of research at Western States Endurance Runs (WSER).
  2. Hyponatremia at WSER
  3. Learn the answer to, "Is sodium supplementation necessary to avoid dehydration during prolonged exercise in the heat?”.
  4. What do we know today about the long term health of ultra-endurance runners? Is ultra marathon running bad for us AND WHY IT MAY NOT EVEN MATTER?
  5. Learn the most important take-home action items from research at WSER that you can put into practice TODAY!
  6. Find out how you can get involved in research at WSER.
Sep 23, 2015
This is the introduction episode, where I tell you about myself and the origin of Science of Ultra, a podcast for ultra marathon runners.