The Eat for Endurance Podcast

Relative Energy Deficiency in Sport - A Discussion with Kristin Duyn, MScN

March 22, 2021 Claire Shorenstein, MS RD CDN with Kristin Duyn, MScN Season 3 Episode 39
The Eat for Endurance Podcast
Relative Energy Deficiency in Sport - A Discussion with Kristin Duyn, MScN
Show Notes

Welcome to Episode 39 of the Eat for Endurance Podcast, during which Kristin Duyn, MScN joins me to tackle the very important topic of Relative Energy Deficiency in Sport (RED-S). Please note that Kristin is  a Certified Sports Nutritionist, NOT a Registered Dietitian. I usually only feature fellow dietitians, but she had a really valuable story to share and we had a great discussion, so I hope you enjoy it.  

What is RED-S? The International Olympic Committee introduced the term in 2014 (think of it as a more inclusive version of the Female Athlete Triad) to include both genders and describe a wider array of negative health and performance outcomes that can result from chronic under-fueling (i.e. low energy availability).

Energy availability (EA) is the amount of energy the body can use to perform normal, necessary functions after accounting for the cost of physical activity, which includes both training and other daily activities. Low EA (and eventually, RED-S) results when the body does not have enough fuel to meet its many energy demands. This may happen unintentionally as training volume increases, or intentionally, from trying to control weight, for example. 

This is a key sports nutrition topic because meeting athlete’s increased energy requirements is essential to optimizing health and sports performance. Many athletes understand this, but still may struggle to fuel appropriately, and that is what I hope to help you with today.

Please note that like with Eating Disorders, RED-S doesn’t have a specific “look,” in terms of body weight or composition. Athletes may experience the repercussions of under-fueling while maintaining the same weight, so please look beyond the scale. 

Here’s what we cover in this episode:

  • Who is at risk for RED-S? What are some warning signs?
  • Kristin’s personal experience with RED-S, chronic injuries, and missed sporting opportunities, 
  • How can we make sure we are eating enough, without obsessively counting calories or macros? 
  • The tricky topic of weight and performance, esp in the context of minimizing risk of under-fueling
  • Amenhorrea (loss of period) - why it happens, why it’s not normal or okay, and getting it back 
  • Male specific issues related to RED-S and under-fueling
  • Recovery after bone injuries

Thank you so much Kristin for chatting with me all about RED-S and putting up with my long, not always well-thought out ramblings on the topic! Clearly this stuff gets me fired up.

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