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I don’t think the most important part of being a healthy, happy runner long-term is running training. I think it’s eating enough food.
First, a digression (that will probably be the first three words on my tombstone). This crap is all so hard. Even knowing all of this stuff about eating and performance and body image and comparison, I find myself judging myself all the time. So cut yourself slack. If you have an eating disorder or disordered eating or body image issues or just don’t always have a comfortable relationship with food, you are not alone. None of this is easy, but that’s why it’s so important to talk about.
As a coach, here’s what I see. Athletes that skimp on calories can have success short-term, but, eventually, it always backfires. Always.
Eating enough is key for long-term, sustainable athletic growth. However, what eating enough means for each athlete varies a ton based on body type, genetics and background. For a detailed breakdown of what you might want to eat and when you might want to eat it, talk to a nutrition expert (like Trail Runner columnist and owner of Fly Nutrition, Kylee Van Horn). The message of this article is way simpler than that: eat lots.
As summarized by the 2019 article, the result is that “an athlete may be weight stable and not excessively low in body mass or body-fat levels yet have impaired physiological function.”
It all gets back to the consequences of “low energy availability.” As reviewed in a wonderful 2019 article in the International Journal of Sport Nutrition and Exercise Metabolism, low energy availability is when energy expenditure through athletics and lifestyle is mismatched with energy intake, leading to either short-term or long-term caloric deficits. That article describes some potential causes of low energy availability, from intentionally restricting calories to inadvertently not eating enough during training. And the potential health consequences of low energy availability can be striking.
One more digression (my outlines look like a Cheesecake Factory menu). A 2014 book chapter from the Encyclopedia of Sports Medicine on low energy availability reviewed the general principle of how it’s related to weight loss. Initially, the body uses energy reserves (essentially stored fats and proteins) for fuel, which can result in changes in body composition. Later, though, the body can reach an energy balance steady state caused by self-preservation mechanisms in metabolic processes. As summarized by the 2019 article, the result is that “an athlete may be weight stable and not excessively low in body mass or body-fat levels yet have impaired physiological function.” A 2013 study in Applied Physiology, Nutrition, and Metabolism even found that some athletes with low energy availability had higher body-fat percentages, likely due to metabolic changes.
In other words, you can’t tell whether low energy availability is a problem with your eyes or a mirror. It’s all so much more complicated than that. Just like any body type can be a runner’s body type, any body type can be subject to low energy availability that has negative health outcomes.
Yet another digression (at this point, digressions are like Fast and the Furious movies). Low energy availability can be within a single day, not just the results of longer-term processes. A 2017 article in the Scandanavian Journal Of Sports Medicine found that when controlling for energy availability in a 24-hour period, female athletes with menstrual dysfunction and metabolic disturbances spent more time in a catabolic state of low energy availability. A 2018 article in the International Journal of Sport Nutrition and Exercise Metabolism had a similar finding for men, with decreased muscle breakdown, worse hormone balance and metabolic disturbances from within-day deficits. So the body doesn’t work on 24-hour cycles. For an athlete, eating enough is a full-time job with overtime.
Sometimes, athletes may need to improve body composition to avoid negative health outcomes like diabetes and heart disease, which is beyond the scope of this article. Talk to a nutritionist or health professional about improving body composition healthily if that is needed for your long-term health. Nutritionist Kylee Van Horn says that it’s important not to deprive the body of what it needs even when trying to change body composition. But the specifics of how to balance athletics and weight loss are complicated and dependent on background/goals.
Instead of delving into those details, the main point of this article is that low energy availability can negatively impact nearly every physiological function involved in being a human being if it’s not done in a strategic and smart way by athletes that need to improve body composition for health. The 2019 article reviewed four of the most prevalent general impacts.
Instead of delving into those details, the main point of this article is that low energy availability can negatively impact nearly every physiological function involved in being a human being if it’s not done in a strategic and smart way by athletes that need to improve body composition for health.
Low energy availabilty in female athletes can result in supressed sex hormones and menstrual dysfunction. In male athletes, it can reduce testosterone. For all athletes, that can impact sex drive and overall health, leading to worse athletic performance and health outcomes.
Relative energy deficiency in sport (RED-S) is when energy intake is too low for training demand, resulting in low energy availability, either acutely or chronically. As articulated by the IOC Consensus Statement from 2018, RED-S can have negative effects on numerous health outcomes, with increased rates of bone-stress injury and other injuries being some of the most prevalent.
A 2018 article in the International Journal of Sport Nutrition and Exercise Metabolism found a five-or-greater-times higher risk of bone-stress injuries in athletes with low energy availability. Similar mechanisms likely apply to soft tissue injuries and overtraining.
Negative metabolic adaptations
The 2019 article reviewed the findings that low energy availability reduces resting metabolic rate, reduced T3 (a marker associated with hormonal health), may cause GI disturbance and could even hurt the immune system.
Performance reductions due to lack of recovery and adaptation
The IOC Consensus Statement reviews that low energy availability slows down recovery and adaptation processes that are essential to develop as an athlete long term. A 2017 article in the Medicine and Science in Sport and Exercise journal found reduced neuromuscular performance in athletes with low energy availability. Other studies show negative consequences for cognitive function and psychological state, which could hurt consistency too. “I notice big changes in recovery time and performance when athletes fuel enough to support their training,” Van Horn says.
Those are just some of the impacts of low energy availability. It’s one of those issues that goes across the scope of what it means to be an athlete and person, so if there is a negative health outcome, it’s likely associated with low energy availability indirectly through hormonal, metabolic and psychological effects.
Van Horn summarizes the stakes: “Oftentimes, when I am working with athletes that have low energy intake, they come to me because they have been stuck in a cycle of injuries that they can’t seem to get out of and overall, just feel tired and drained all of the time. Once they start to dial in appropriate nutrient intake, they can tell a difference in energy levels and health, sometimes as quick as a week after making changes.”
Oftentimes, when I am working with athletes that have low energy intake, they come to me because they have been stuck in a cycle of injuries that they can’t seem to get out of and overall, just feel tired and drained all of the time. Once they start to dial in appropriate nutrient intake, they can tell a difference in energy levels and health, sometimes as quick as a week after making changes.
I am not a nutritionist, so my advice about what to eat isn’t going to be all that helpful. However, these issues are so ubiquitous that I have focused on three main points for athletes thinking about energy availability.
No food is bad food
Giving labels to food can be a slippery slope, so try to give yourself the love to enjoy what you enjoy without judgment. I like athletes to eat burgers, pizza and ice cream if they enjoy those foods, with the understanding that fueling the body is an act of love, not obligation.
In an ideal world, all of your nutrition would be real, whole foods. But if the option is eating “clean” or eating enough, I’d choose eating enough every single time no matter how much ice cream that requires.
Fat and protein and carbs are all your friends
The body needs it all, so make sure you give your body all of it. I don’t love athletes to track macronutrients because it can be a slippery slope to unhealthy behaviors, so just keep it coming and work with a nutrition expert for further guidance. Meals should probably not be math equations.
“Food should be celebrated, not feared,” Van Horn says. “Changing our perceptions can make a big difference in our stress levels and training/performance goals.”
Find your strong
The final message is more about what it means to be an athlete. Every single person reading this is a superstar athlete, even if it doesn’t manifest itself in competitive results. You are using your body to do amazing things. It might be a run, it might be lifting up the kids, it might be anything that involves your body using energy to perform. The goal in that process is not necessarily to reach a finish line the fastest. The goal is to find your strong.
What’s your strong? It could be a fast mile, it could be doing your first 10-mile week, it could be running 100 miles in 15 hours, it could be making the Olympics, it could be playing pick-up soccer with your kids. Your strong won’t be the same as someone else’s. Your strong might look entirely different. It might have a different dress size. It might have cellulite or extra skin or scars. Maybe you’re fast as heck or maybe you have endurance or maybe your victory is getting around the block.
That variation is the beauty of being uniquely you. It’s what we should celebrate and lift up and cheer on. And whatever your strong is, eating enough is an essential way to support it.
—David Roche partners with runners of all abilities through his coaching service, Some Work, All Play. His book, The Happy Runner, is about moving toward unconditional self-acceptance in a running life, and it’s available now on Amazon.