You're not seeing things. CoachCast has been renamed Endurance Unlimited. Stay tuned for more great episodes and more. Now, on to this episode... Dr. Iñigo San-Millán explains the science and strategy behind optimal cycling nutrition. Learn how TrainingPeaks' new Fueling Insights feature leverages decades of his metabolic research data to help athletes and coaches evaluate and individualize fueling plans based on athlete metrics, not guesswork. From breaking through the outdated 40-gram carb ceiling to personalizing race-day nutrition for every level of today's cyclist, learn how this tool is changing how we plan, perform and recover. 03:34 Iñigo Intro and Current Roles 07:50 Revamping Carbohydrate Intake for Athletes 12:41 Metabolic Flexibility 14:28 Pioneering Carbohydrate Oxidation Research 19:08 Fat Oxidation Misconceptions in Athletes 21:07 FATMAX: Peak Fat Oxidation Point 26:30 Race Performance and Energy Expenditure 27:48 Balancing Glycogen for Athletes 31:05 Cyclists' Nutrition & Intensity 38:31 Fueling Insights Workout Calculation Steps 39:48 Metabolism Variability Among Individuals 44:32 Risks of Fasted Workouts 47:16 Understanding Gross Efficiency Limitations 56:54 The Nutrition Evolution Learn more about Fueling Insights Learn more about TrainingPeaks Episode 1, Season 5: The Biochemistry of Zone 2

The evolution of paddle sport racing is pushing the limits of endurance competition, where training technology and data-driven coaching play a significant role. April Zilg, world champion paddle athlete, joins the show to share her journey from "couch potato" to the top of the stand up paddle board (SUP) world—all powered by smart training, dedication and data. In this episode, April reveals how technique-focused coaching, a science-based approach to training and leveraging TrainingPeaks shapes her work with athletes of all levels. Get a crash course in the many flavors of paddle sports—from lightning-fast sprints to epic 1,000-mile adventures—and how race type, equipment and environment shape effective training strategies. April stresses the importance of tracking progress, balancing intensity and recovery, and being open to new technology, including heart rate and (soon) power meters on the water. Whether you're curious about SUP racing, endurance coaching, or just want a peek behind the paddle, this episode is full of valuable coaching and training tips.

In this episode, host Dirk Friel sits down with professional gravel racer and Ignition Coaching coach Dylan Johnson to dig into all things gravel. They break down the cutting-edge equipment trends seen at the 2025 edition of Unbound Gravel, as well as training trends, nutrition and training tips for both amateurs and pros. Hear why mountain bike tires are dominating the scene, the evolving role of aerodynamics in the sport, and the reasons behind faster race times over the last few years. Whether you're a seasoned cyclist or a gravel-curious newcomer, you'll hear expert advice on your next gravel race and the new "Unbound Block" approach to training. Dylan also offers a glimpse into the future of even faster gravel racing. To learn more about Dylan Johnson, check out his training plans or follow him on YouTube and Instagram.

In this episode of the CoachCast, host Dirk Friel sits down with Kristen Arnold, a registered dietitian, elite cycling coach, and former pro racer, to unpack the complex relationship endurance athletes often have with food and body image. Drawing from her coaching and clinical experience, Kristen explores how disordered eating patterns can quietly surface in training environments that overemphasize being lean, disciplined, or performing at any cost. Kristen offers practical strategies for coaches and athletes to identify red flags, reframe food as fuel (not a reward or punishment), and prioritize long-term health alongside results. From race-day fueling to an off-season mindset, this conversation challenges outdated norms and empowers listeners to pursue performance with compassion, curiosity, and balance. Resources discussed in this episode: Environment and Language Guide for Discussing and Managing Physique USOPC Sports Nutrition Resources for Young Athletes Directory of Registered Dietitians Sports Nutrition for Women E-Course HEXIS App Fulein App

In this episode, Dirk Friel talks with Alex Martin, a former professional motocross and supercross racer who spent over 15 years competing at the highest level, earning podiums and top-five finishes. After retiring from racing as a pro, Alex leaned into his passion for training and performance, co-founding Troll Training. His coaching company blends motocross performance with endurance sports methodologies. Alex shares his journey from motocross to recently catching the “running bug” and how structured training, especially via TrainingPeaks, helped him transform his racing career and life after retirement. He just raced the 2025 Boston Marathon, finishing at 2:48:35, just shy of a PR, with plans to run several other big races in the coming months. From building marathon fitness as a busy dad and coach to balancing strength, endurance, and recovery in high-risk motorsports, Alex shares an insider’s look at taking advantage of experience and science to advance the art of coaching unique athletes.

Matt Dixon shares his clear and simple approach to coaching, emphasizing the importance of purpose, consistency, and developing foundational habits over chasing the latest trends or technologies. Whether you're an ambitious amateur or a seasoned pro, this episode has valuable takeaways to optimize your training and life balance. Matt is the founder and CEO of Purple Patch Fitness, a coaching company that caters to endurance athletes of all levels. Under his guidance, more than 1,500 Purple Patch athletes have qualified for the IRONMAN World Championships. He's an IRONMAN U master coach, a former professional triathlete, and a two-time Olympic trials finalist in swimming with a master's degree in clinical and exercise physiology. Despite the common perception that high-volume training is essential for success, Matt demonstrated that a focused regimen, averaging about 10 hours per week tailored to fit an athlete's lifestyle, was just as effective. While running a large tech company, one of his athletes won an IRONMAN World Championship overall as an amateur on a 10-hour-per-week training plan.

We're diving deep into the world of professional cycling camps as we hear first-hand from some of the leading coaches and nutritionists in pro cycling. Reporting from the picturesque coastal climbs of the Costa Blanca in Spain, our host, Dirk Friel, brings you insights from performance coaches like Lieselot Decroix and Mattia Michelusi, who reveal the critical training techniques employed to enhance rider performance. Learn how pro teams leverage lactate testing, hear what metrics WorldTour coaches focus on around functional reserve capacity (FRC), and background on the growing importance of heat training. Nutritionist Nicki Strobel gives us a taste of what meal planning looks like during grueling tours and how data from TrainingPeaks is used to tailor nutrition strategies. Plus, Stephen Barrett explains the significance of durability in today's WorldTour races, while Liam Holohan shares insights on hypoxic training. Whether you're a coach, athlete, or enthusiast, this episode is packed with proven takeaways to help elevate your training to the next level. Special thanks to   FDJ-Suez — https://www.fdj-suez.fr/ Decathlon AG2R La Mondiale — https://decathlonag2rlamondialeteam.com/ Team Cofidis — https://www.equipecofidis.com/uk/home Israel-Premier Tech — https://israelpremiertech.com/

In this episode of the TrainingPeaks CoachCast, we sit down with Fergus Crawley, the co-founder and head coach of Omnia Performance, to look into the world of hybrid athletes. Hybrid training, a blend of strength and endurance disciplines, challenges the traditional boundaries of athletic training. Fergus draws from his rich background in rugby, powerlifting, triathlons, and concurrent training to explain how athletes can effectively balance opposing athletic goals. From his incredible achievement of squatting 500 pounds and running a sub-five-minute mile in the same day to working with military operatives, Fergus shares insights on biomechanical awareness, periodization, and the mental approach needed for such diverse training programming. Learn how hybrid athletes can tackle the demands of multi-discipline sports and the benefits of open-mindedness in fitness. Fergus discusses several strategies he uses to coach and accomplish his many challenges that can help you pursue your athletic goals, whether you're a seasoned triathlete or a strength enthusiast curious about endurance.

Professional runner and running coach Nell Rojas shares her insights into racing and coaching athletes for marathons, including the Boston Marathon, using a balance of art and science. She attended Northern Arizona University, where she studied exercise science and competed in cross country and track. Nell ran her first marathon in 2018 and became the top American finisher in the Boston Marathon in 2021 and 2022. Additionally, she finished 10th at the 2022 New York City Marathon. Nell has achieved remarkable success as an American marathon runner, securing top American finishes at the 2021 and 2022 Boston Marathons, a top 10 finish at the 2022 New York City Marathon, and competing in the 2020 Olympic Marathon Trials. She has also claimed a 10-mile US Championship title and won Grandma's Marathon. Beyond her athletic accomplishments, Nell advocates for inclusivity within the running community, focusing on empowering people of color and women. With 20 years of coaching experience, she is dedicated to helping athletes of all abilities achieve their own running goals.

Scott Johnston, co-author of "Training for the New Alpinism" and "Training for the Uphill Athlete," shares insights on recovery strategies for ultramarathon runners in this new podcast episode. Johnston emphasizes the critical balance between rest and performance, outlining how factors like central nervous system fatigue, motivation, and age influence post-race recovery. The conversation highlights actionable strategies, including subjective feedback tracking, active recovery, and the importance of long-term planning for peak performance while avoiding overtraining. Visit TrainingPeaks.com to see how it can help your training.

Listen in as indieVelo creator George Gilbert and TrainingPeaks president Lee Gerakos break down the reasoning behind the acquisition of the virtual riding platform, now named TrainingPeaks Virtual, the opportunities for coaches and athletes and how the ethos of credible virtual racing is a part of the DNA of the merger.  They share with Dirk the importance of community feedback in shaping the platform's development and commitment to creating inclusive and credible virtual racing environments. Plus, learn about the seamless integration of TrainingPeaks athlete accounts and TrainingPeaks Virtual and its impact on cycling training and community building. The options for creating group rides, races and training simulations are extensive for coaches and athletes. 

Gale Bernhardt's insights on effective coaching, balancing technology with human touch, setting long-term goals and tips for aspiring coaches. With over 35 years of coaching experience, Gale Bernhardt has guided Olympians and World Championship athletes and played pivotal roles as the USA Triathlon Olympic and Pan American Games Triathlon coach. She shares her incredible journey from a mechanical engineering background to becoming one of the most respected figures in endurance sports as a pioneering endurance coach. We explore her coaching philosophy, emphasizing the importance of continual learning across exercise science, pedagogy, and other key areas of understanding. Gale also provides invaluable advice for aspiring coaches. She highlights the significance of setting long-term goals, addressing knowledge gaps, and balancing science and the art of coaching.  Gale and Dirk compare and contrast coaching occupations in the United States and European countries. Plus, she touches on the evolving role of AI in coaching and why the human touch remains irreplaceable. To learn how TrainingPeaks can help your endurance coaching, visit TrainingPeaks.com.

Understand the essentials of athlete fueling, including RED-S and the importance of tailored nutrition plans, with sports dietician Kylee Van Horn. Kylee Van Horn, CEO of Fly Nutrition, specializes in helping athletes optimize their performance and manage eating disorders, including RED-S (relative energy deficiency in sport). She's also an ultrarunner and running coach based in Colorado, looking to simplify nutrition for athletes and steer them away from fad diets. You can also hear her on the podcast "Your Diet Sucks" with Zoë Rom. In this episode, Dirk and Kylee break down personalized nutrition plans, the role of micronutrient density, and the importance of understanding fuel requirements for different training sessions. Kylee shares helpful tips on fueling strategies for endurance and ultra-endurance athletes, addressing common fueling challenges, and the benefits of a team coaching approach to addressing nutrition and training goals. Plus, you'll hear her thoughts on addressing a few situations as an athlete, like overcoming nausea and the difficulty in recognizing eating disorders. To help structure your endurance sports journey, visit TrainingPeaks.com.

Heart rate variability (HRV) is unique to each athlete. Learn how to effectively measure and use HRV data alongside subjective feedback to optimize your training and recovery. Our guest for episode 10 is Marco Altini, a scientist, app developer and expert in using data from wearable devices to optimize health and performance. Many will recognize his name from the app HRV4Training, which integrates with TrainingPeaks. Marco's background spans computer science, human movement and high-performance coaching. He's also an avid runner, having qualified for the Boston Marathon and competed in European ultramarathons. Our discussion digs into the details of HRV, an increasingly popular metric for endurance athletes. Marco breaks down what HRV actually measures, its history of use in scientific research, and how it serves as a marker of the body's response to various stressors — from training to travel to simple daily life. He also clears up some of the biggest misconceptions about HRV, like the idea that you can directly compare your HRV to someone else's or that a single HRV reading can predict if you're about to get sick or injured. Marco emphasizes the importance of context and tracking your individual trends over time to have a valid baseline to analyze your stress response. Perhaps most importantly, we cover how HRV data is best used as one piece of the puzzle in understanding your body so that you can have productive training sessions.   To learn how TrainingPeaks can help your training, visit https://trainingpeaks.com/

Explore insights from top coaches Ryan Bolton and Erin Carson on preparing U.S.A. triathletes for the 2024 Olympic Triathlon competitions and, in one instance, the individual time trial in cycling, through coaching collaboration and training techniques. In this episode, Ryan Bolton and Erin Carson discuss the details of preparing athletes for the 2024 U.S. Olympic Triathlon team in Paris. Ryan Bolton, Director of High Performance for U.S.A. Triathlon and owner and founder of BEST Coaching brings extensive experience as an Olympian for the 2000 games and coaching top-tier athletes, including 2024 Olympian Morgan Pearson. Erin Carson, a renowned strength coach and head coach at ECFIT Performance Strength, shares her unique perspectives on optimizing athletes' physical and mental resilience, including Taylor Knibb. The coaches also break down the elements that separate Olympic athletes from other elite athletes, the explosiveness of modern triathlon races and the resources Team U.S.A. is deploying for this year's competitions to aim for the best results. Learn more about TrainingPeaks and how it can improve your endurance sport performance at trainingpeaks.com.

In this special episode for the Tour de France, Iñigo San Millán, a performance coach for UAE Team Emirates, shares his expertise on how race-day nutrition is meticulously planned and adjusted using race data from TrainingPeaks. We'll discuss the critical differences in fueling demands for various stages of the Tour, the importance of individualized nutrition strategies, and why maintaining weight and muscle health is crucial for rider performance. From pre-race breakfasts to post-race recovery with tart cherry juice, this episode is packed with pro-level insights that even amateur athletes can leverage. Learn more about TrainingPeaks and how it can improve your endurance sport performance.

In this special episode, we explore the insights of Amine Issa, Ph.D., on the intersection of gaming and numerous disciplines, such as esports, Formula 1, and even the military. Amine has spent 25 years obsessively playing video games and even competed professionally. He spent five years researching the extremes of human performance at the Mayo Clinic. His findings help develop new technology and techniques to assess human-integrated physiology, specifically in mobile health and remote monitoring. In studying performance optimization in athletic, military and esports fields, he has discovered a clear overlap between esports athletes and traditional performers and how gaming skills can translate to broader contexts. He discusses the value of "range" and mental strategies in gaming and highlights the evolving roles of coaching, sports psychology and fitness within the esports industry. Whether you're a coach, gamer, or just curious about the intersection of gaming and performance, this unique episode will open your mind to new concepts. Amine is now the founder and CEO of Mobalytics, a gaming performance assessment and optimization platform. They aim to help all competitive gamers learn from their data to make meaningful improvements — not dissimilar to endurance athletes using data for better performance. This interview was conducted at a TrainingPeaks All-Staff, where we regularly gather and learn from experts in fields other than endurance athletics.  Learn more about TrainingPeaks and how it can improve your endurance sport performance.

In this episode, we sit down with John Wakefield, the managing director of Science to Sport and performance coach with the Bora-hansgrohe World Tour cycling team. John, from Cape Town, South Africa, shares his insights from years of coaching and an advanced training facility in Girona, Spain. Understand why recovery is the key to progression and how ignoring it can impede an athlete's performance, no matter their level. John believes recovery is the critical element in athlete training. He shares details about a routine 'sub-max test' he utilizes with his athletes, whether pro or amateur. He can document progression and shape optimal training by using power and heart rate data in concert with subjective feedback from an athlete on wellness factors like sleep, stress, and mood. Recovery isn't just about easy days or days off. John breaks down other factors to consider in recovery protocols, like stretching, nutrition, massage, and mindfulness, to fulfill the "Three Rs:" refuel, rebuild and rehydrate. He also takes us inside a team bus to learn some of the cyclists' critical recovery strategies while competing in a Grand Tour.  Learn more about TrainingPeaks and how it can help optimize your training.

Björn Geesman is a German-based sports scientist and coach. He is also the CEO of HYCYS coaching company and co-founder of power & pace. He works with pro triathletes Patrick Lange and Kat Matthews, among other big names in endurance sports.  In this episode, Dirk and Björn dive into everything from wind tunnel testing tunnels and bike selection based on data to the importance of sports psychology to his potentially controversial approach to the "long run" — even at the professional levels of sport. He also explains how the science and data learnings from pros can relate to athletes competing in age group races and events. Yet, reminding us all that it's essential not to get lost in excessive analysis but to focus on impactful training. 

Dr. Will O'Connor takes us through the nuances of using running power in training. Will and Dirk get into the scientific side of power meters, discuss the accuracy and data consistency from devices like Stryd and other wearables, and learn how to use critical power zones to break down the metabolic costs of running variable terrain. Will also touches on some of the lessons in his Fundamentals of Running Power TrainingPeaks University course. Will is a running scientist and former triathlete based in New Zealand. He drew on his background in organic chemistry to complete a Ph.D. in Sport & Exercise Science from Massey University, where his research investigated metabolic flexibility and ketogenic diets in ultra-endurance performance. Will competes at the elite level in ultrarunning events — he's used a run power meter since day one — and is a coach and host of the "Running with Dr Will" podcast.