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Are you UNDERFUELING?: The signs and risks of underfueling your training and how to combat it

By Jaqueline Perez, MS RDN

Take this scenario. Eric is a starting running back for his high school football team. He is trying to get recruited to his top choice university. He knows he needs to get stronger, put on more muscle mass and improve his speed, all whilst scoring touchdowns on the field. At the start of September, he has practice every weekday along with a game on the weekends AND he lifts three times a week. Occasionally, when he has time on weekends, he also runs sprints to work on his speed. At the start of the season, Eric feels great. He feels fast, strong, energetic and still keeps up with his school work. Come October, he starts to feel worn down, tired, and cannot focus well during class. His workouts are becoming harder and he is starting to see his performance on the field suffer. He hasn’t changed his training regimen. Eric wonders, “What am I doing wrong?”

For starters, Eric is exerting a lot of energy and putting his body through physical stress from his training. However, he hasn’t made any major changes to his training regimen in the last month. All the signs point to UNDERFUELING. Let’s dive in.

Underfueling is what occurs when you are expending more energy than you are taking in which puts your body into a NEGATIVE energy balance. To put it simply, you are not eating enough calories to maintain your current activity level. In most cases, this is not going to benefit your performance. It’s important to recognize the signs that you may be underfueling. Also, it is vital that you know the risks associated as they may be life changing.

Here are some signs that you may be underfueling:

  • Hunger: If your stomach is grumbling and you feel hungry, your body is trying to tell you something. FEED ME!

  • Fatigue or low energy levels: You may feel unusually tired even with a solid night’s sleep or generally just feel worn out

  • Muscle cramping: Getting muscle cramps soon into a workout even if you thought you hydrated well may be one of the first signs

  • Increased perceived exertion of performance: No change in workout regimen but somehow your training seems harder. Might be time to take a deeper look.

  • Brain fog: This may come as poor concentration, forgetfulness or reduced mental sharpness

  • Poor sleep: You may be having trouble falling asleep or frequently wake up during the night

  • Gastrointestinal distress: This can include stomach cramps, diarrhea, bloating and gas

  • Stalled weight loss: If weight loss is a goal with your specific training and you have plateaued, it may be a sign you are underfueling (again this is if weight loss is desired)

  • Poor recovery: A case of the DOMS (delayed onset muscle soreness) is not the same as poor recovery. If you’re feeling sore a week after your hard workout or you’re not bouncing back like normal after a good lift, your body may not be responding as well during the recovery process

If you do recognize any of these symptoms, it may be time to look a little deeper into your daily food intake and hydration as well as your training regimen.

There are several risks associated with underfueling. Some are short term but there are also long term risks to be aware of especially in the case of chronic underfueling.

Short term risks include:

  • Dehydration

  • Weight loss

  • Decreased performance

  • Injury

Long term risks include:

  • Bone fracture

  • Loss of lean body mass

  • Hormonal changes

  • Complications from injury

  • Weakened immune system

So, HOW do you combat this and help prevent chronic underfueling? Here are some tips to to consider:

  • Eat when you're hungry: Your body has naturally occurring hunger hormones and when it needs more food, your hunger hormones will kick into drive to let you know!

  • Don't skip meals: Skipping meals can put you into an unnecessary energy deficit. In the case that you know you won’t sit down to a meal in a timely manner, have some snacks available on hand to fuel your activities.

  • Take a rest day, if needed: A recovery day does the body good. It helps with muscle recovery as well and mental recovery.

  • Pay attention to the color of your urine!: It sounds funny but hydration is also part of fueling. Paying attention to the color or your urine is an easy tip to help you recognize you might need to hydrate more. Darker, brown urine typically indicates you are under hydrated. Click this link to see a chart of what urine color you should be looking for

  • Work with a dietitian!: Seeing a dietitian can be extremely beneficial especially if you have specific training goals in mind or if you’re having trouble figuring out what to eat to fuel properly. Dietitians can help formulate a plan that works best for YOU!

Overall, be sure you are listening to your body and giving it what it needs. Fueling your body properly will help with muscle recovery as well as allow you to perform at the level you're striving for. Food is FUEL!

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