A familiar term that shows up regularly in the running scene when it comes to female runners is the athlete triad. Quite simply it is the intersection of three clinical entities: menstrual dysfunction, low energy availability and decreased bone mineral density. These three have regularly been evaluated together, offering treatment solutions to individuals in addressing this trifecta of issues.

But in some cases, it is not all three that are occurring simultaneously, and researchers have recognized that there are several instances in which these entities do not occur concurrently, or can be unrelated. Addressing this in a new concept, experts have begun to evaluate Relative Energy Deficiency (RED): “A syndrome of health and performance impairments resulting from an energy deficit.” Through this topic of research in the last few years, experts are trying to piece together the best way to recognize, assess and treat RED.

One recent study yielded big gains when it comes to understanding why some days the energy tank feels like it’s just plain empty when it’s time to put in the miles. Results showed that one of the symptoms depicted by test subjects presenting with low energy availability included decreased training response as well as decreased endurance performance, among several others including impaired judgement, irritability and depression.

And while ultimately low energy availability did indicate it was more likely to lead to individuals having an increased risk of poor bone health, and menstrual dysfunction, it also showed a risk of cardiovascular impairment, psychological disorders and gastrointestinal dysfunction. It is the combination of the decreased capabilities in training and symptoms indicative of these latter four risks that you may see showing up in your own training and, in turn, affecting your performance.

If you’re sitting there reading this and thinking that you have been feeling quite drained lately, that training hasn’t been going to plan, or that your irritability has hit new levels, you may find yourself saying, “Do I have low energy availability?”

  • Do you have an increase in upper respiratory tract symptoms or illness, such as a cold, congestion or impaired breathing?
  • Body aches that won’t go away?
  • Gastrointestinal symptoms that are out of the ordinary or that have shown up in recent months?
  • An overwhelming sense of being unable to cope with simple daily tasks that require mental energy or planning?

Symptoms in these areas are what researchers showed to be indicative of low energy availability.

The study also indicated a series of performance variables, and this low energy can translate across to training as well. As runners, we’ll ignore being sick, feeling tired or having a short fuse with the kids because, well, marathon training does that to you. But mess with the marathon training and we’ll jump into action. And there are indeed several ways low energy availability starts to present itself in training as well:

  • Abnormal stomach issues on long runs or feeling like you have an increase in stomach related issues that weren’t a problem for you before.
  • Difficulty concentrating and focusing during training sessions – i.e. can’t get “in the zone.”
  • Loss of or decrease in your typical level of mental strength and resilience on long runs.
  • Overall feeling of lethargy and fatigue both when running and not running, in ability to push through fatigue and reach the energy output levels you are used to.

While we all have those days when it is hard to muster up the energy to get out the door or when the run feels really hard, leaving us particularly drained, continuous low energy availability presents itself differently. It is long-lasting and the energy never really seems to be there. In other words, it’s more than just an off day or bad run.

And when that happens, and low energy availability is indeed to blame, it may be a sign of something bigger. In fact, an increase in training volume and intensity, even gradually over time, can lead the body to have insufficient energy to fulfill basic bodily functions to stay healthy and recover properly.

If your training response and performance is starting to suffer because you just don’t have the energy to get it to where you want to be, or you notice a persistent series of symptoms not readily explained by “I’m training for a marathon,” give your body a rest and then consider seeking the help of a professional to get you back on track.