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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 From breaking through the outdated 40-gram carb ceiling to personalizing race-day nutrition for every level of today's cyclist, learn how this tool is changing how we plan, perform and recover.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.