Part of the challenge of racing an Ironman (or any race) is making it to the start line. Every year, we see big names unable to race the biggest races, whether it be due to injury, illness, or otherwise. I would love to see a statistic on how many pros who qualify for world champs do not make it to the start line. Maybe 20%? Depending on the year? Obviously, there’s many factors that contribute to getting to toe the line.
Which leads me to today’s topic, which I think is one of the biggest issues we have in the sport of triathlon: under fueling, low energy availability, and RED-S. I’ll get into the definitions here of each in a bit, but I have to wonder how much better athletes would perform, and how much stronger the quality of field at events could be if there was a stronger focus on fueling training sessions compared to the focus of body weight. Now, I’m not lost on the fact that power to weight is an important aspect of many endurance sports. But if the focus on weight precedes focus on adequate fueling and recovery, then we have a problem. Currently, the sport of triathlon has this precise problem.
I think it’s important to note here that it’s impossible to say that the reason all athletes fail to start a race is due to underfueling. That’s a rash conclusion and impossible to say definitively from an outside perspective. Do I think it’s possible underfueling impacted some of them? Absolutely. We know that under fueling increases risk of illness and injury… the reasons why many athletes are unable to start races.
RED-S stands for Relative Energy Deficiency in Sport and is a syndrome with “impaired physiological functioning caused by relative energy deficiency and includes, but is not limited to, impairments of metabolic rate, menstrual function, bone health, immunity, protein synthesis and cardiovascular health." The cause of RED-S is a mismatch between an athlete’s energy intake (input) and energy expenditure (output), leaving inadequate energy to support necessary functions for health. RED-s includes a broad spectrum of health, physiological and performance outcomes in both females and males, and can occur in individuals regardless of body size. This mismatch of energy intake (low) to energy output (high) which leaves inadequate energy available for normal physiological processes is what’s known as Low Energy availability (LEA).
RED-S is an evolution of the Female Athlete Triad. The female athlete triad was known as a relationship between low energy availability, menstrual dysfunction, and decreased bone mineral density. Over the years, the female athlete triad was expanded by RED-S as we’ve learned that the condition not only affects women, but also men, and the spectrum of health consequences associated with LEA is much larger than just menstrual dysfunction and low bone mineral density.
Other Symptoms of RED-S
We’ve heard for years about inadequate energy (calorie) intake, low bone mineral density, stress fractures, and missing periods. Yet, it’s amazing to me the number of stories I’ve heard of healthcare practitioners dismissing missed periods as acceptable as “normal for female athletes”, or the use of contraceptive pills as a band aid fix to get periods back (it’s not) without addressing the calorie deficit which initiated the problem. However, some symptoms of RED-S that people experience may not be initially associated with low energy availability, like for example, gastrointestinal issues.
The human body is resourceful. If decreased energy is available, certain functions deemed as less significant to survival will diminish in capacity. Let’s say you’re being chased by a bear. Is it more important to digest the food in your system or direct energy needs to your leg muscles so you can run away? This is why there’s a correlation between LEA and increased incidence of gastrointestinal distress than in athletes with Adequate Energy Availability.
If calories are scarce, many hormonal changes occur. This likely happens to conserve energy to allow for the most vital body functions to continue. Another function you don’t need to survive? Reproduction. Testosterone lowers in males, and men may experience low sex drives. Menstrual disruptions happen in females. Athletes may also experience sleep disruptions, irritability, or depressed moods.
In fact, low energy availability negatively impacts a multitude of processes including cardiovascular health. High cholesterol and hypoglycemia (low blood sugar) is more common for women suffering from LEA than women with adequate energy availability. Although exercise is protective against cardiovascular events, high cholesterol associated with LEA may have long term negative health consequences.
Training and Recovery
In my opinion, one of the greatest factors which results in peak athletic performance is the ability to train consistently. Stacking day after day to create small, consistent improvements over time. Frequent injuries, or illness will impact an athlete’s ability to do this. Other, less known symptoms of RED-s ">include decreased coordination, decreased concentration, and impaired judgement, factors which culminate into increased injury risk. Low energy intake can also be both cause and a symptom of iron deficiency anemia, impairing oxygen delivery to body tissues making it difficult to train.
There is some evidence suggesting that the risk of illness is three times higher in athletes at risk of LEA compared to those without. Injury risk could be 4.5 times higher for LEA athletes, which is no surprise considering the impact of reduced energy availability of bone mineral density and recovery.
Eventually, low energy availability leads to athletic performance decline. Athletes may not see it right away; some may even have an increase in performance before things totally fall apart. In an effort to conserve energy, metabolism decreases, causing a reduction in lean mass, resulting in undesirable changes in body composition. Inadequate carbohydrate and protein intakes lead to decreased glycogen storage and reduced protein synthesis, which means athletes will see less performance gains from training.
RED-S is a multifactorial condition in athletes. Whether the cause is unintentional under fueling, disordered eating, or eating disorder, the outcome can be the same. It’s a common thought to “workout so I can eat”. Instead, athletes will benefit from implementing a “fuel so I can train” perspective. Like the gas tank of a car, you won’t be able to run on empty forever, Eventually, there is a breaking point, and it will eventually come at the cost of health and athletic performance.