The effects of not eating enough calories on an athlete

Apr 17, 2019

What would happen if we tried to “guess” how much our expenses would be? Oh, I think my car payment is around $XXX and then my mortgage is usually $XXX so I am guessing my paycheck should be somewhere around $XXX.  As you can see you will find yourself in a lot of unneeded stress and potentially overdraft charges.

Our body has overdraft charges but they comes at the expense of using energy meant for other body systems. In the short-term you may have enough energy you can manage. However, over time you could become a tired, injury ridden athlete.

Tapping into the Emergency Fund

Our bodies have three major storage areas of energy that can be used: liver (glycogen) , muscle and body fat. At first the body depletes our body fat (savings account). If you are guessing at your expenses and having to use your savings account to pay monthly bills this doesn’t leave much for the emergency fund. Our body fat is our emergency fund. This emergency fund is how we survived during famines, provide nourishment during pregnancy and fuel for necessary growth. Our bodies will fight to keep its emergency stash as its first instinct is always survival not optimum performance.

Perform not Preserve

In my career I have learned we can use reference points for where an athlete may be best fueled. The best practice is to always consider personalizing. Research has demonstrated that generally the body needs at least 45 calories per pound of lean body mass. Once it goes below 30 calories per lean body mass the body starts to adapt to preserve not preform.  Unless you have had body composition tested it is best to not try to guess what you think your body composition is.

In the book “Finding your Sweet Spot in Sport” I hope you can learn signs from your body that may signal your energy balance is off and how to correct it. Ultimately teaching one to prevent RED-S by doing a systems check- in during season.

 Fill up your energy bucket

  • Click here to listen to Nancy Clark as she discusses the athlete bucket and why you must fill it up.
  • Allie Kieffer shares how using her energy and strength became her most powerful attribute.

Next blog will discuss why our body fat is a very powerful tissue that deserves our respect!


  1. Heather on April 20, 2019 at 2:27 pm

    Thanks for sharing this reminder. As a cancer survivor, I always try to be aware of my energy reserves and listening to my body’s needs.

    • Becca McConnville on May 20, 2019 at 6:21 am

      Heather- great point and thank you for sharing!

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Becca McConville

ReBecca McConville, MS, RD, CSSD CEDRD

"The life-long athlete in me wants to make sure that all athletes stay at the top of their game for as long as they choose to be in their sport. This book will keep athletes on track before your season starts, in the grind of the season, at the end of your season—and be ready to go for the next one."

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