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How to Properly Fuel and Prevent that Sluggish, Fatigued, and Worn-Out Feeling

You cannot run without gas in the tank!

Close your eyes for a moment and imagine a well-kept new car. You get in the driver’s seat and rev up the engine. You start driving and everything feels great! Then the car starts to slow down and sputters to a complete stop. This car is supposed to be fast, agile, and able to endure long distances so why did it stop so suddenly? Well, to be blunt, it was out of FUEL.

In simple terms, the human body works just like a car. It needs fuel to keep running and it needs to be taken care of to minimise the daily wear and tear it takes on.

As an athlete, it is even more important to properly fuel your body to reach optimal performance. The American College of Sports Medicine says, “Adequate food and fluid should be consumed before, during, and after exercise to help maintain blood glucose concentration during exercise, maximize exercise performance, and improve recovery time”¹.

Properly fuelling is all about the QUALITY, QUANTITY, TIMING, COMPOSITION, and BALANCE of the nutrition you are putting into your body.

This alone is already a lot to juggle, but today, there are so many opinions of “right” and “wrong” ways to prepare for and recover from exercise, it makes finding answers even more difficult. But that’s the thing — There is no singular cookie-cutter regimen that guarantees optimal performance for every single athlete. An athlete’s nutritional needs vary depending on:

• sport & exercise duration
• environmental exposures
• age
• fat-free mass
• stress & illness
• medications, and more²

Although it may take some time to find a regimen that works well for you, it’s important to have an open mind and a baseline understanding of how pre, during, and post nutrition works to steer you in the right direction!

The Ins and Outs of Fuelling Pre, During, and Post Workout

The best way to get your body and mind prepared for a killer workout is to rack up energy. Your body uses the molecule glucose (from carbohydrates) as its main energy source during exercise, so you want to make sure you have plenty of it on hand.

Extra glucose is converted into GLYCOGEN and stored away for later use. When we exercise, we are using glucose as our fuel so when levels get low, we tap into those glycogen stores. An effective way to improve endurance is to consume good carbohydrate sources before the start of exercise to increase the glycogen stores in skeletal muscle and the liver³.

Some of the best carbohydrate sources you can eat 2-3 hours prior to working out include whole-grain cereals (with low fat or skim milk), whole-wheat toast, low-fat or fat-free yogurt, whole grain pasta, brown rice, and vegetables. These foods are high in fibre and known as COMPLEX CARBOHYDRATES, meaning they take longer to digest and absorb but they contain more sugars and provide large amounts of sustainable energy!

Good carbohydrate sources to eat 60-90 minutes prior to a workout are fruits and refined carbohydrates. These are SIMPLE CARBOHYDRATES containing a considerable number of sugars and are easily digested and quickly absorbed.

It is just as important to know what foods to AVOID when preparing for a workout. Riska Platt, M.S., R.D., suggests avoiding foods with saturated fats and large quantities of protein because they require the digestive system to put in more work to break them down which takes away oxygen and energy from your muscles¹. Avoiding these types of foods will also minimise gastrointestinal issues, which are no fun for anyone (we’ve all been there!).

Similarly, foods high in fibre should also be avoided too close to a workout because of their slow digestion rate. Fibre right before a workout, especially long endurance workouts, can cause digestion issues and an upset stomach. Athletes may want to look towards refined carbohydrates (low in fibre) such as white bread rather than whole-grain sources of carbs before a workout for easier and quicker digestion and absorption.

Commonly, athletes overlook the need to fuel DURING their workouts. This kind of fuelling is necessary for endurance athletes exercising for over 2-3 hours.

Rehydrating and replenishing glucose and electrolytes as you go could be the difference between BONKING(“hitting the wall”) or not. Fluids or supplements packed with easily digestible/absorbable carbohydrates and electrolytes will resupply the body with the hydration and nutrition it needs to prevent bonking.

Finally, let’s talk about RECOVERY. Consuming the right foods at the right times is one of the most important aspects of recovering after a workout. In fact, eating within 30 to 60 minutes after your workout is crucial to help with muscle repair⁵.

Post-workout nutrition should incorporate both protein and carbohydrates — Carbohydrates help rebuild glycogen stores and prevent muscle breakdown, while protein helps remodel, rebuild, and renourish those muscles.

In fact, to effectively repair and rebuild skeletal muscle tissues, the American Colleges of Sports Medicine and the International Society of Sports Nutrition recommends a protein intake of 1.2–2.0 grams per kilogram of body weight per day⁶.

Appropriate protein intake keeps lean body mass healthy⁷ and encourages muscular recovery from strenuous exercise, preparing you for your next workout!

What About Hydration?

Properly hydrating pre, during, and post-workout is vital for optimal athletic performance. In fact, it is not uncommon for athletes to lose 2–10% of their body weight in sweat during long endurance events. If fluids are not replenished, it can lead to a decline in physical performance⁴.

Water aids in many important functions while your body is exercising such as:

• regulating body temperature- sweat helps keep you cool
• transporting nutrients throughout your body
• lubricating joints
• supporting proper muscular strength and control

According to The U.S. National Academies of Sciences, Engineering, and Medicine, adequate fluid intake is about 15.5 cups of fluid a day for men and 11.5 cups of fluid a day for women⁸.

As an athlete, it is important to stay hydrated and replenish nutrients lost during exercise such as water and electrolytes to avoid the effects of becoming dehydrated. Even under mild levels of dehydration, the effects can severely impact athletic performance by reducing stamina and motivation, increasing the feeling of fatigue, altering thermoregulatory capability, and increasing perceived effort⁴.

In addition, very severe and dangerous complications can arise from dehydration such as hyperthermia (body temperature above normal range), reduced cardiac output, decreased blood pressure, and reduced blood flow to the muscle. So, as you are fuelling your body with the proper nutrients, do not forget about the H₂O!

Signs You’re UNDERFUELLING!

BONKING! All athletes know that crushing feeling of bonking or “hitting a wall” during their workout. There just isn’t anything left in the tank, your legs feel like bricks, and it feels like your body just suddenly decided to shut down.

Bonking is one of many effects of not getting enough fuel and sufficient recovery. Your body will try to tell you it’s not getting the energy it needs to support the energy it's expending by enhancing feelings of fatigue, soreness, and weakness⁹. These effects are obviously not ideal for striving for optimal performance and can hinder any degree of exercise by:

• increasing perception of fatigue
• depleting glycogen stores
• hitting the wall (bonking) more quickly
• breaking down lean muscle mass
• decreasing motor skills
• decreasing concentration and motivation
• increasing risk of injury¹⁰

Chronic under-fuelling or depriving your body of the fuel it needs for extended periods of time can lead to hair loss, bad skin, brain fog, nutrient deficiencies, intestinal and gut disturbances, anxiety, poor sleep quality, weakened immune function, bone fragility, and even a loss of thyroid function⁸. These signs and symptoms can be your body telling you it needs more food and fluid — The best thing you can do is LISTEN to it!

You Get What You GIVE

Simply, you GET out of your body what you GIVE it.

Properly fuelling and recovering with nutritious foods, at the appropriate times, in the right amounts are all ways to give back to your body as well as stay hydrated. The human body can do so many incredible things and endure such great stress if given the appropriate tools to do so. As athletes, we want our bodies to move faster, work longer, and be stronger — To achieve that, we must put in the work in our everyday lives to prepare and recover.

Think back to the car analogy. If you don’t give your vehicle the fuel and maintenance it needs, it won’t be able to get you to where you want to go. Our bodies can take us to extreme heights — We just must give it the FIREPOWER to do it!

Resources

1. American Heart Association. Food as Fuel Before, During and After Workouts. Published January 2nd, 2015. Accessed September 1st, 2021 https://www.heart.org/en/healthy-living/healthy-eating/eat-smart/nutrition-basics/food-as-fuel-before-during-and-after-workouts
2. Jeffrey R. Bytomski. Fuelling for Performance. First Published November 27, 2017 Research Article. https://doi-org.uc.idm.oclc.org/10.1177/1941738117743913
3. Aoi, W., Naito, Y. & Yoshikawa, T. Exercise and functional foods. Nutr J 5, 15 (2006). https://doi.org/10.1186/1475-2891-5-15
4. Popkin BM, D'Anci KE, Rosenberg IH. Water, hydration, and health. Nutr Rev. 2010;68(8):439-458. doi:10.1111/j.1753-4887.2010.00304.x https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2908954/
5. Cleveland Clinic healthessentials. The Best Ways to Fuel Your Workouts Might Surprise You: The truth about protein shakes, plus what to eat. Published August 27th, 2020. Accessed September 1st 2021https://health.clevelandclinic.org/the-best-ways-to-fuel-your-workouts-might-surprise-you/
6. Alexandra Caspero, MA, RD. Protein and the Athlete — How Much Do You Need? Published July 20, 2020. Reviewed April 2020. Accessed September 1st, 2021 https://www.eatright.org/fitness/sports-and-performance/fueling-your-workout/protein-and-the-athlete
7. Vliet SV, Beals JW, Martinez IG, Skinner SK, Burd NA. Achieving Optimal Post-Exercise Muscle Protein Remodeling in Physically Active Adults through Whole Food Consumption. Nutrients. 2018;10(2):224. Published 2018 Feb 16. doi:10.3390/nu10020224 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5852800/
8. Mayo Clinic Staff. Water: How much should you drink every day? Water is essential to good health. Are you getting enough? These guidelines can help you find out. Published October 14th, 2020. https://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/in-depth/water/art-20044256
9. Jessie R. Shafer. Oxygen Magazine. OrthoCarolina Are You Underfueling? Published June 15th, 2020. Accessed September 2nd, 2021. https://www.orthocarolina.com/media/are-you-underfueling
10. Human Performance Resources by CHAMP Uniformed Services University. Underfueling carbs can lead to underperformance: In-depth. Published April 15th, 2020. Accessed September 2nd, 2021. https://www.hprc-online.org/nutrition/performance-nutrition/underfueling-carbs-can-lead-underperformance-depth