RED-S Revisited

Recently, an old Hansons teammate, now Olympian, Jacob Riley, made public a pretty severe case of RED-S. By the sounds of it, the deficiency really took a toll on Jacobs’s health and performance. How does that happen to a guy at the top of his game? That’s probably a discussion only he can answer, but it got me thinking about more than just a few of the athletes I come in contact with. As part of our personal coaching package, we offer athletes a free nutrition consult and guide. One of the biggest things we see is the underfueling (and hesitancy to accept that they are) to support the training they are doing. The question is why? Usually, they want to “lean out” but aren’t necessarily at a weight that would warrant losing poundage. They are eating, but their idea of enough calories is something that even a dietician would want to be monitored by a professional. Basically, they aren’t eating, but they aren’t losing weight, and they feel “puffy.” Now, I don’t necessarily want to get into all that, but I do want to discuss RED-S, what practical info you can take, and what the long term implications of insufficient caloric intake can be even if it’s not in the traditional sense of severe undereating. 

RED-S stands for relative energy deficiency for sport. Basically, what we are looking at is if you are taking in enough calories to support the work that you are doing. Here’s what we are calculating

Energy Availability = (Daily Energy Intake – Daily Energy Exercise Expenditure) / Fat Free Mass

This is expressed in kcal/kgFFM/day. So to calculate this you need to know how much you are eating, how much you are burning, your weight (in kg), and your body fat percentage. 

I’ll use myself as an example. 

Let’s say I weigh 155 pounds. That’s equal to 70.45 kg  (wt in pounds divided by 2.2). I think my body fat percentage is about 12%. This means 70.45 x .12 = 8.45. 70.45-8.45 = 62 kg of fat-free mass. 

We will I assume I eat 2500 calories a day and I burned 1200 through running and strength training. 

My equation will look like this:

EA = (2500-1200) / 62 OR 20.96 kcals per FFM per day. Ok great, but what does that mean?

The truth is, there’s not a lot of long term study data out there. A lot of what we are using is coming from very short term study data (3-5 days), cross sectional data, and case studies. What we know right now is that 45 kcal/kg FFM/day is basically a net zero caloric intake per day and so 40-45 is where you should try to be if you just want to maintain weight. Once you get to <30 per day, that’s when problems really start to show. Things like immune function, muscle protein synthesis, fatigue, dyslipidemia, and endothelial function. 

Let’s use the example of a 120 pound female with about 15% body fat. This would be a pretty common woman we work with. If they eat 2,000 calories but burn 1,000 calories a day, that’s an EA of about 21. What if they do a long run, but eat the same amount of calories? That puts her down to about a 10! You can see how you might not be too bad on some days but really off on other days! So as I am thinking about it, what does this mean in a practical manner? 

I go back to what we do know from studies- short term deficits can probably actually boost performance by burning some unwanted fat weight, but long term it’s not good. So, a missed day here and there is what it is. My guess is that a lot of athletes have some swings below 30 and to 45. My problem is that we know below 30 can wreak havoc over time and that a 40-45 average is where the sweet spot is. However, what if someone is averaging somewhere in between? This is where I feel a lot of athletes could find themselves unintentionally. 

This self-proclaimed “danger zone” is what intrigued me and makes sense when I look at a lot of our athletes. The decline is so gradual over a very long period of time that it doesn’t stick out as the main issue. They aren’t starving themselves. They aren’t restricting their diet, but are they truly eating enough to support their training. Over the months and years, they find themselves fatigued, plateaued out, and with nagging injuries. However, it’s easy and logical to say it’s hard training. Where I’d be interested in is athletes who fit this description, and how they track weekly and monthly on average over a training segment. 

Where are we from a practical standpoint? 

Tracking food intake everyday prob won’t happen. I actually really don’t like the idea of counting calories for extended periods of time. What I would do instead is get an idea of how much you need to maintain a 40-45 type number on certain types of days. What I mean by that is, that how much energy intake you need for a short easy day is less than a long run day. If you know about what you need for different types of days, you can let that guide you. So, what I might do is track what I am eating and know what I’m burning over these different days and then use that to guide me. Maybe calculate what these numbers might look like as training volume increases. 

Getting athletes to add a significant number of calories across the day can be tough. Let alone when you ask them to eat more carbs. If this is you, then maybe where we start isn’t with your daily food intake, but your workout nutrition. If we can get you to take in a pre-run fuel, then really work on during exercise fueling, and top it off with the post workout recovery, then your main meals and snacks may only need small tweaking. Not only is it important to get enough fuel, it’s also important to get the right fuel at the right time. This will certainly help with a few areas of training and performance. 

At the end of the day, I can see how people across the spectrum can completely miss something like RED-S. But If you feel like you are plateaued in performance, are constantly fatigued, dealing with nagging injuries, or always fighting off a cold, then this is something that you can pretty easily check out. The big question will be if you are willing to fix it.

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