Endurance Eats

Your labs came back “normal”… but you’re exhausted, your training feels harder than it should, and something still feels off.
Iron deficiency is incredibly common in female endurance athletes and if ferritin isn’t being checked, you could be missing a really important piece of the puzzle.
Today on the Endurance Eats Podcast, we’re talking about iron deficiency in endurance athletes, particularly female athletes.
I’m joined by Dr. Cory Dugan, a postdoctoral research fellow at the LSU Pennington Biomedical Research Center and a researcher in iron deficiency and women’s health. Cory earned his PhD from the University of Western Australia, where his work focused on iron deficiency management and treatment in active females.
My goal with this episode, along with my three-part ferritin series on Substack, is to give you the knowledge and language you need to better advocate for yourself at your doctor’s office.
We’re breaking down what ferritin actually tells us, why hemoglobin alone doesn’t give us the full picture, why female endurance athletes are especially vulnerable to low iron stores, and what we actually know about iron deficiency, fatigue, and athletic performance.
Because being exhausted all the time shouldn’t automatically get written off as “normal.”

What You’ll Learn
The difference between iron deficiency, iron deficiency without anemia, and iron deficiency anemia and why knowing the difference matters

Why your hemoglobin can look completely normal while your iron stores are already running low

Why ferritin is one of the most important numbers to understand when you’re looking at iron status

Why there’s still so much disagreement around what counts as “low” ferritin

Why Cory advocates for looking beyond the traditional ferritin cutoff, especially in athletes

How hard training and inflammation can affect ferritin and potentially make your results harder to interpret

Why female endurance athletes have so many overlapping risk factors for iron deficiency, including menstrual blood loss, GI blood loss, sweat losses, foot-strike hemolysis, and exercise-induced changes in iron absorption

And if you’ve ever been told your labs are “fine” while you’re still wondering why you feel so tired, this is an episode I really want you to hear.

Resources Mentioned
 My three-part ferritin series on Substack

PART 1: Ferritin: The Number No One Agrees On

PAR 2: Ferritin Low, Everything Else Normal: Now What?

PART 3: Iron and Ferritin - Supplementing Smart

Dr. Cory Dugan’s website 

Dr. Cory Dugan on Instagram 

Dr. Cory Dugan on LinkedIn 

Dr. Cory Dugan’s free iron risk questionnaire 

Dr. Cory Dugan’s plain-language iron guide for women 

“The Misogyny of Iron Deficiency” by Dr. Cory Dugan 

Connect with Me:
Follow along for more practical sports nutrition and fueling support: Instagram: @alexlarsonnutrition

Website: alexlarsonnutrition.com

Work with Alex Larson Nutrition: https://alexlarsonnutrition.com/

Check out our endurance nutrition tools and resources 

Don’t Forget to Subscribe!
Click that follow button to stay updated on future episodes packed with actionable insights and expert advice for endurance athletes. Leave a quick review to help more endurance athletes find the show

Have Questions or Suggestions?
Send me a message, and I might cover it in a future episode!

This episode of Endurance Eats is brought to you by Alex Larson’s 1:1 Nutrition Coaching.
If you’ve ever wondered, Am I eating enough? Am I fueling this right? Why do I still feel tired? you’re not alone. Alex Larson Nutrition helps endurance athletes cut through the confusion and build a fueling plan that actually works for their training, lifestyle, and goals.
You can learn more at alexlarsonnutrition.com. 

This Episode is Brought to You By Carb Culture Shop
Grab your merch from the shop with saying that endurance athletes just get!

This episode is brought to you by Thorne. 
Shop Thorne Supplements and get 15% off  https://www.thorne.com/u/alexlarsonnutrition

What does it actually mean to be a woman in endurance sports right now?
I’ve been thinking about this episode for more than a year, and I knew I didn’t want it to be another conversation focused only on the challenges women face. So I asked three incredible professional female endurance athletes the same four questions and their answers went in directions I think we all need to hear.
Because what our bodies can do is a whole lot more interesting than what they look like.
In this special episode of the Endurance Eats podcast, I’m bringing together three professional athletes from three different corners of endurance sport: Olympic marathoner Dakota Popane, 2022 IRONMAN World Champion Chelsea Sodaro, and professional gravel cyclist Cecile Lejeune.
We talk about what they love about being women in sport, how they wish we talked about female athletes differently, the conversations our sports still aren’t having enough, and what they want the next generation of girls and women to know about performance and body image.
We also get into the media’s fixation on female athletes’ bodies, the need for more women-specific sports research, motherhood and professional sport, athletic longevity, and why preserving the joy of sport matters.
These are three very different perspectives and that’s exactly what makes this conversation so good.

What You’ll Learn
Why getting beaten by a woman should never be treated as an insult and what that attitude says about the way we still view women’s performance

What Dakota, Chelsea, and Cecile genuinely love about being women in endurance sports

Why the conversation around female athletes needs to move beyond weight and appearance and toward performance, preparation, tactics, and mindset

What the coverage of the 2025 Tour de France Femmes revealed about the way we talk about women’s bodies in elite sport

Why women-specific research still has a long way to go and why better research matters for athletes at every level

How pregnancy, motherhood, sponsorships, and professional sport collide in ways we still aren’t talking about enough

Why longevity shouldn’t mean only staying physically healthy, it should include protecting your mental health and your joy in sport

What some of the best women in endurance sports want younger female athletes to understand about their bodies

Why helping the next generation develop a healthier relationship with food and body image starts with what we model for them

The reminder I hope every athlete takes from this episode: being strong, powerful, and capable matters so much more than chasing a certain appearance

Resources Mentioned

Dakota Popane — Endurance Eats Episode 47

Chelsea Sodaro — Endurance Eats Episode 56 

Cecile Lejeune — Endurance Eats Episode 33 

Dr. Abbie Smith-Ryan — Endurance Eats Episodes 25 & 26: 

Follow Dakota Popane 

Follow Chelsea Sodaro 

Follow Cecile Lejeune 

Connect with Me:
Follow along for more practical sports nutrition and fueling support: Instagram: @alexlarsonnutrition

Website: alexlarsonnutrition.com

Work with Alex Larson Nutrition: https://alexlarsonnutrition.com/

Check out our endurance nutrition tools and resources

Don’t Forget to Subscribe!
Click that follow button to stay updated on future episodes packed with actionable insights and expert advice for endurance athletes.

Have Questions or Suggestions?
Send me a message

This episode of Endurance Eats is brought to you by Alex Larson’s 1:1 Nutrition Coaching.
If you’ve ever wondered, Am I eating enough? Am I fueling this right? Why do I still feel tired? you’re not alone. Alex Larson Nutrition helps endurance athletes cut through the confusion and build a fueling plan that actually works for their training, lifestyle, and goals.
You can learn more at alexlarsonnutrition.com. 

This Episode is Brought to You By Carb Culture Shop
Grab your merch from the shop with sayings that endurance athletes just get!

This episode is brought to you by Thorne. 
Get 15% off Thorne Supplements

What if eating better could actually help you sleep better and sleeping better could make it easier to fuel your body well?
It turns out these two things are way more connected than most athletes realize. And if you’ve ever noticed that you’re absolutely ravenous after a terrible night of sleep…there’s a reason for that.
In this episode, I’m joined by nutrition and sleep researcher Marie-Pierre St-Onge to dig into the fascinating, bi-directional relationship between sleep and nutrition.
Marie-Pierre’s background is in nutrition, and her research explores how sleep duration, diet quality, meal timing, and other lifestyle factors influence energy balance and cardiometabolic health. She’s also the co-author of Eat Better, Sleep Better.
And I loved this conversation because it confirms something my team and I see with our endurance athletes all the time: when we improve how an athlete fuels during the day, sleep often improves right along with it.
We talk about what happens to hunger when you’re sleep deprived, why eating more earlier in the day may benefit both sleep and metabolic health, and what athletes with evening workouts can do when training and bedtime are uncomfortably close together.
We also get into magnesium, tart cherry juice, melatonin, sleep trackers, women’s hormonal changes, and why your watch’s sleep score shouldn’t necessarily dictate how you feel about your day.

What You’ll Learn
Why sleep and nutrition have a bi-directional relationship, meaning poor sleep can change how you eat, while what you eat may also affect how well you sleep

What happens to hunger and satiety hormones when you’re sleep deprived and why you may legitimately feel hungrier after a rough night

Why overeating after several nights of poor sleep isn’t necessarily a willpower problem and what I want you to get curious about instead

What researchers found when people restricted their sleep by about 90 minutes for six weeks

Why a higher-quality diet with more fruits, vegetables, fiber, whole grains, nuts, and seeds is associated with better sleep

The fascinating connection between eating five servings of fruits and vegetables per day and less fragmented sleep

Why I’m such a fan of front-loading nutrition

How eating later in the day may affect your body’s ability to wind down for sleep

What the research actually says about magnesium, tart cherry juice, melatonin, and GABA for sleep

Why consistent bedtimes and wake times matter and how “social jet lag” can affect your health and eating patterns

How hormonal changes throughout the menstrual cycle and the menopause transition may influence women’s sleep

Why your Garmin, Apple Watch, Oura Ring, or other sleep tracker can be useful data but shouldn’t override how you actually feel

Resources Mentioned

Marie-Pierre St-Onge’s website

Marie-Pierre St-Onge on LinkedIn 

Eat Better, Sleep Better by Marie-Pierre St-Onge and Kat Craddock 

Marie-Pierre St-Onge’s interview on the Huberman Lab podcast 

Connect with Me:
Instagram: @alexlarsonnutrition

Website: alexlarsonnutrition.com

Don’t Forget to Subscribe!
Click that follow button to stay updated on future episodes packed with actionable insights and expert advice for endurance athletes.

Have Questions or Suggestions?
Send me a message, and I might cover it in a future episode!

This episode of Endurance Eats is brought to you by Alex Larson’s 1:1 Nutrition Coaching.
If you’ve ever wondered, Am I eating enough? Am I fueling this right? Why do I still feel tired? you’re not alone. Alex Larson Nutrition helps endurance athletes cut through the confusion and build a fueling plan that actually works for their training, lifestyle, and goals.
You can learn more at alexlarsonnutrition.com. 

This Episode is Brought to You By Carb Culture Shop
Grab your merch from the shop with saying that endurance athletes just get!

This episode is brought to you by Thorne. 
Shop Thorne Supplements and get 15% off  https://www.thorne.com/u/alexlarsonnutrition

If your stomach always seems to betray you on race day, your gel might not actually be the problem.
GI issues can come from how hard you're racing, what you ate the day before, dehydration, caffeine, nerves, travel, hormones, or even how you're carrying your fuel. In this episode, we’re breaking down the surprisingly long list of things that can send your gut sideways—and what you can do before race day to lower the odds of an emergency porta-potty stop.
In this episode, Hanna, Mary, and I dig into why athletes experience nausea, reflux, cramping, loose stools, and other GI problems during endurance events and how we troubleshoot them with our athletes. We talk about everything from pre-race nerves and racing harder than you train to carb loading, fiber, caffeine, hydration, travel, hormones, and underlying physiological issues.
Most importantly, we explain why there’s no one-size-fits-all solution. Your best defense is practicing your strategy, paying attention to patterns, and creating a race-day plan that works for your gut.

What You'll Learn
Why your race pace—not your sports nutrition—might be behind your GI issues

How nerves and adrenaline can completely change your appetite and ability to tolerate food

Why B and C races—or full race-day simulations—can expose fueling problems before your A race

How to practice fueling during hard efforts instead of always taking nutrition during recovery periods

Why carb loading can backfire when fiber, fat, or fructose gets too high

The surprisingly important connection between coffee, caffeine, and your pre-race bathroom schedule

Why dehydration can wreak havoc on your gut during longer endurance events

How travel, time zones, late race starts, and disrupted routines can change your digestion

Why blindly copying a pro athlete’s caffeine or electrolyte strategy can be a recipe for trouble

When persistent GI problems may have nothing to do with nutrition—and when it’s time to involve your healthcare team

Resources Mentioned

Precision Hydration sweat testing  

Previous carb-loading episode 

FREE Carb Loading 101 Guide https://alexlarsonnutrition.myflodesk.com/carb-loading

If you’re experiencing chronic GI issues and can’t figure out what’s causing them, consider working with our team or another sports dietitian experienced in endurance nutrition:  https://alexlarsonnutrition.com 

Connect with Me:
Instagram: @alexlarsonnutrition

Website: alexlarsonnutrition.com

Don’t Forget to Subscribe!
Click that follow button to stay updated on future episodes packed with actionable insights and expert advice for endurance athletes.

Have Questions or Suggestions?
Send me a message, and I might cover it in a future episode!

This episode of Endurance Eats is brought to you by Alex Larson’s 1:1 Nutrition Coaching.
If you’ve ever wondered, Am I eating enough? Am I fueling this right? Why do I still feel tired? you’re not alone. Alex Larson Nutrition helps endurance athletes cut through the confusion and build a fueling plan that actually works for their training, lifestyle, and goals.
You can learn more at alexlarsonnutrition.com. 

This Episode is Brought to You By Carb Culture Shop
Grab your merch from the shop with saying that endurance athletes just get!

This episode is brought to you by Thorne. 
Shop Thorne Supplements and get 15% off  https://www.thorne.com/u/alexlarsonnutrition

Sports fuel has come a LONG way, and we love that endurance athletes have more options than ever. But if you’re training for long-course triathlon, cycling, running, or another high-volume endurance sport, you also know how quickly those gels, drink mixes, and hydration products can add up.
So… can you just make your own?
In this episode, Alex Larson is joined by sports dietitian Mary Wirtz to nerd out on all things DIY sports fuel. We’re breaking down what actually goes into high-carb drink mixes, why the ratio of glucose to fructose matters, and how athletes can customize their own fuel based on carbohydrate and sodium needs.
We also talk about one of the biggest reasons athletes are experimenting with homemade sports nutrition: cost. One athlete they work with calculated his homemade mix at just $0.85 per 100 grams of carbohydrates, compared with several dollars per serving for many commercial sports fuel products.
But cheaper doesn’t automatically mean better. DIY fuel takes planning, accurate measuring, and a good understanding of your individual fueling needs. Sometimes paying for the convenience of pre-made packets is absolutely worth it, especially on race day.

In this episode, we cover:
What to look for in high-carb sports drink mixes

Why combining glucose and fructose can help athletes absorb more carbohydrates

How the wrong carbohydrate balance may contribute to GI issues during long endurance events

Why some athletes combine high-carb mixes with electrolyte products

How to DIY a sports drink using maltodextrin or dextrose, fructose, and sodium citrate

The 2:1 and 1:0.8 glucose-to-fructose ratios

Why you’ll want a food scale if you’re making your own sports fuel

How much money DIY sports nutrition could potentially save

The pros and cons of homemade fuel versus pre-packaged products

How to make DIY sports gels using high-carb drink mix, maple syrup, or other options

Creative hydration ideas including electrolyte popsicles, cherry recovery soda, and a frozen electrolyte “margarita”

Why your fueling strategy should ultimately be customized to your training, sweat losses, intensity, and individual tolerance

Whether you’re trying to bring down the cost of fueling a huge training block or you simply love experimenting with your nutrition, this episode will give you plenty of ideas to start exploring.
And remember: more DIY doesn’t necessarily mean more complicated. The goal is finding a fueling strategy that gives your body what it needs while actually being practical enough to use consistently.
If you need help figuring out your carbohydrate, hydration, or sodium needs for training and race day, the sports dietitians at Alex Larson Nutrition can help you build a strategy that works for your body and your sport.

This episode of Endurance Eats is brought to you by Alex Larson’s 1:1 Nutrition Coaching.
If you’ve ever wondered, Am I eating enough? Am I fueling this right? Why do I still feel tired? you’re not alone. Alex Larson Nutrition helps endurance athletes cut through the confusion and build a fueling plan that actually works for their training, lifestyle, and goals.
You can learn more at alexlarsonnutrition.com. 

This Episode is Brought to You By Carb Culture Shop
Grab your merch from the shop with saying that endurance athletes just get!

This episode is brought to you by Thorne. 
Shop Thorne Supplements and get 15% off 

Resources Mentioned in This Episode:
 Apply for 1:1 Coaching with an ALN Dietitian

FREE Carb Loading 101 Guide

Episode Mentioned

Kitchen Scale

Connect with Me:
Instagram: @alexlarsonnutrition

Website: alexlarsonnutrition.com

Don’t Forget to Subscribe!
Click that follow button to stay updated on future episodes packed with actionable insights and expert advice for endurance athletes.

Have Questions or Suggestions?
Send me a message, and I might cover it in a future episode!