The Cost of Under-Fueling

When I first got into running seriously, I fell in love with the process.

I loved watching my mileage increase, seeing my fitness improve, and setting bigger goals for myself. I became focused on training. Every week I was adding more kilometers, chasing new personal bests, and setting new goals for myself. However, what I wasn’t paying attention to was my nutrition. The issue wasn’t the quality of my diet; it was the quantity. I was choosing nutritious foods, but what I overlooked was that as my mileage increased, so did my nutritional needs and I was not adjusting my intake to match that. At first, my body seemed to keep up. I was running more, getting fitter, and seeing improvements. Eventually, my body started sending me signals that something wasn't right.

The Signs Were There.

·      My performance plateaued.

·      My pace times stopped improving.

·      My sleep quality suffered.

·      My recovery felt slower than it should have.

·      I began picking up more injuries.

·      My iron levels dropped significantly, eventually becoming so low that I required an iron infusion.

·      The most concerning, I lost my menstrual cycle.

I think I knew what was happening long before I was willing to acknowledge it. My body was sending clear signals that something was off but admitting I wasn't eating enough would have meant confronting some beliefs and fears that I wasn't ready to face. Instead, I told myself I needed to work harder, be more disciplined, and push through it. The reality was that my body wasn't letting me down, it was adapting. It began adjusting to conserve energy and protect essential functions.

Running a Deficit

At some of my peak training periods, I was running over 100 kilometers per week and yet I was eating a maximum of around 2,200 calories per day. To put that into perspective, a single 10-kilometer run can burn anywhere from 600 to 800 calories depending on the athlete, pace, and terrain. That means I was burning an additional 6,000 to 8,000 calories every week from running alone and that didn't include my other activities

• Strength training

• Walking

• Daily activities

• Work

• Recovery needs

• The energy required to simply keep my body functioning

Realistically, I should have been consuming somewhere around 3,000 calories per day, if not more during heavier training blocks. Most importantly, those calories needed to include a significant amount of carbohydrates to support endurance performance. Clearly, I wasn’t even close.

The Fear of Eating More

The hardest part wasn't learning how much food I needed, the hardest part was overcoming the fear of eating it. I think many female athletes or just females in general can relate to this. I was struggling with body image concerns and disordered thoughts around food and performance. I genuinely believed that increasing my calorie intake would automatically lead to weight gain. I feared losing the body composition I thought a runner was supposed to have and so I continued to under fuel.

Unfortunately, many endurance athletes fall into this same trap. We celebrate our increased training volume, our discipline and pushing through discomfort. I think in today’s world especially there is a belief that lighter is faster. While body composition plays a key role in performance, the result ends up being that athletes focus on weight loss rather than building a body that is strong, resilient and properly fueled. Every day we are exposed to messages that reinforce this idea. Weight loss medications have become part of mainstream conversation and social media feeds are filled with weight-loss advertisements and images of “perfect” bodies. People have stopped chasing strong and are chasing small. Research suggests that under-fueling and low energy availability is surprisingly common among endurance athletes, particularly in female athletes. There are significant percentage of female athletes that experience symptoms associated with RED-S. I was one of those individuals who fell victim to this and that is how I developed RED-S (Relative Energy Deficiency in Sport)

“RED-S occurs when an athlete consistently consumes less energy than their body requires to support both exercise and normal physiological function. When there isn't enough energy available, the body begins prioritizing survival over performance, and the consequences can be detrimental:”

• Decreased performance

• Poor recovery

• Increased injury risk

• Chronic fatigue

• Hormonal dysfunction

• Loss of menstrual cycle

• Reduced bone health

• Compromised immune function

• Iron deficiency

• Mood changes

• Sleep disturbances

Time to Wake-Up

The body can compensate for a surprisingly long time before the consequences become impossible to ignore. My moment became pretty clear during the Calgary Marathon. I went into that race tired; I went into that race injured. And most importantly, I went into that race under-fueled. My goal was to qualify for the Boston Marathon. I had trained hard and had sacrificed but what I really sacrificed was that I had not given my body the fuel that it needed. Halfway through the race, I bonked and it was a real struggle to just cross the finish line. I didn't qualify for Boston. Looking back now, it was one of the most important lessons of my running journey.

One of the biggest misconceptions I had was believing that eating less would help me maintain a leaner physique. Ironically, chronic under fueling can often make body composition goals harder to achieve. When the body experiences prolonged energy stress, several adaptations occur.

·      Increased Water Retention

o   When energy intake is too low, stress hormones such as cortisol can rise.Higher cortisol levels can increase water retention, leaving athletes feeling bloated, puffy, and heavier despite training hard.Many runners experience this during heavy training blocks and mistakenly assume they need to eat even less.

·      Reduced Daily Movement

o   Your body becomes incredibly efficient when energy is scarce. You may unconsciously:

§  Move less throughout the day

§  Fidget less

§  Feel more fatigued

§  Reduce non-exercise activity

·      Loss of Lean Muscle

o   When calories and protein are insufficient, muscle repair suffers. Over time, athletes can lose lean muscle mass and negatively affect body composition.

·      Hormonal Changes

o   Thyroid hormones

o   Reproductive hormones

o   Recovery processes

o   Stress hormones

For female athletes, the loss of a menstrual cycle should never be viewed as normal or a sign of fitness. It is often a warning sign that the body does not have enough energy available to support healthy function and I did not have a menstrual cycle.

Fueling My Potential

It took time to change my mindset. It took conversations with friends, and it took a lot of positive self-talk. Most importantly, it took realizing that food wasn't the enemy. Fueling properly didn't make me slower. It made me stronger, improved my recovery, my performance, my health. Today, I view nutrition as part of my training plan, not separate from it.

If you're increasing your training volume, are you increasing your nutrition to match it?

I like to think that I have grit but no amount of grit an overcome an empty tank. After Calgary I made the conscious effort to eat more. I increased my carbohydrate intake. I stopped trying to “earn’ my food and started recognizing it as fuel for performance, recovery, and overall health. It took some time to come back but eventually my energy and recovery improved. My training became more consistent. Eventually, my menstrual cycle started to return. That process took a long time and honestly, I still struggle with this. The longer it is absent, the harder it can be to get it back. Once I started properly fueling, my training and my running changed. I went into my next marathon fueled, healthy, and prepared.

I achieved my goal.

I qualified for the Boston Marathon.

Not because I trained harder. Not because I ran more kilometers. Because I finally gave my body the fuel it needed to perform. I carried that lesson into my next two marathons. At the Chicago Marathon, I ran a personal best of 3:11. The difference was consistency, proper recovery, and adequate fueling. The truth is, I still struggle from time to time. Even as a nutrition and running coach, I still experience some of the same body image challenges that many women face. Those thoughts don’t simply disappear. Now I chose how to respond to them. I learned a lot about the importance of positive self-talk. I remind myself of what proper fueling allows me to do. Sometimes when I need it, I get a swift kick in the ass from the ones I love.

Sometimes being properly fueled might mean carrying a few extra pounds and that's okay. My goal is no longer to be the lightest version of myself. My goal is to be the strongest version of myself. I am chasing big goals for myself, and I can’t achieve those goals if I am measuring success by the number on the scale.

My next goal is a sub-3-hour marathon and that cannot be achieved without a full tank.