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Running and body composition: a slippery slope

Canadian Olympian Erin Teschuk and Athletics Canada sports dietitian Jen Sygo talk about the intersection between body composition and performance, and the pervasiveness of body shaming in sport

When news broke two months ago detailing the body-shaming that was taking place on the Oregon Ducks track and field team, most runners were upset — but few, sadly, were shocked. The “thinner equals faster” mentality has been pervasive in sport for decades, and the pressure on athletes, particularly females, to meet certain body composition standards has been constant. We spoke with Canadian Olympian Erin Teschuk and Athletics Canada sports nutritionist Jen Sygo about the relationship between body composition and athletic performance, and how body shaming became so endemic in track and field.


Teschuk, who competed in the NCAA at North Dakota State University and who competed for Canada in the 3,000m steeplechase at the 2016 Rio Olympics, counts herself lucky that she’s never experienced any direct body-shaming during her career. “I’ve fortunately had coaches that really emphasize performance and recovery over bodyweight, but I know that’s not everyone’s experience in college athletics,” she says. “I know a lot of girls who have experienced body shaming from coaches either directly or indirectly.”

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Still, Teschuk struggled with the pressure to “look like a runner.” “Body image and expectations really affected me throughout my career when I started having success in track and field,” she says, “and I felt that if I really cared about this sport and wanted to be the best I could be, I had to be extremely strict with my diet and try to look like what I thought a successful runner should look like.” Teschuk added that while this thought process came from a good place, which was the drive and desire to be her best, it ended up having a negative impact on her career. She eventually lost her period, which led to fatigue and burnout, and it took a lot of time and patience to get herself healthy again.

Body composition and athletic performance

Sygo explains that in theory, an athlete who has an optimal power-to-weight ratio (in other words, someone who is stronger and lighter) is expected to have more success in their sport, especially in a ground-contact sport like running. In reality, she says, it’s not quite that simple, and it is not the case for many athletes. “If humans were just robots, if we didn’t have the complexities that we have, both psychologically and physiologically, then we could create the perfect diet plan or perfect weight for each athlete,” she says, “and that would make them as fast as they possibly could be.”

The problem with this is that in real life, athletes may be affected emotionally by restricting intake in order to meet a certain bodyweight a coach has dictated for them, and could fall into disordered eating patterns or develop a full-blown eating disorder. Athletes could also develop physical issues, like RED-S (relative energy deficiency in sport), which will eventually impact their ability to run well.

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Initially, athletes who change their diet to lose weight do get faster, but the performance boost doesn’t last. Sygo likes to use the analogy of a house. “If you imagine that a house costs a certain amount of money to run every month — the mortgage, the bills, the upkeep and any upgrades you may want to make to it,” she says. “Now imagine I said I’m going to give you $1,000 dollars less of what you need to maintain that house every month. Just for a month, you might be able to get by, by turning down the thermostat and maybe not buying any new things. It wouldn’t be a great month, but you wouldn’t be too far in the hole.”

As time goes on, however, your house will really start to fall apart. Sygo says this is what happens to a person when they’re chronically underfuelled. They might be able to get away with it for a little while, but the longer things go on, the more they start to break down.

When you start fuelling yourself properly again, you may not see the payoff right away. Just like with the house, if you give back that $1,000, it won’t fix everything if you’ve been in the hole for six months. “When an athlete comes out of a deficit and has been fuelling themselves well for long enough, then all of the sudden wonderful things start to happen,” says Sygo. “They also start to enjoy the sport more.”

Changing the conversation

Sygo says that in order to reverse the faster-is-thinner mentality, it has to start from the ground up. There needs to be education for athletes and coaches at all levels from our sport’s governing bodies, like Athletics Ontario and Athletics Canada, as well as through the National Coaching Certification Program (NCCP). While these conversations are happening now, as Sygo says, “you can’t turn the Titanic around in a day, but you can over time.”

Sygo encourages all athletes to trust their instincts. If they have the feeling that they’re not themselves anymore, or they’re struggling with their training, mood and motivation, those are all really good signs that they need to pay attention. Working with a sports dietitian is an excellent way to improve your eating habits and make sure you’re fuelling yourself properly, but she says if you think you’re drifting into disordered eating habits and you don’t feel you manage the change on your own psychologically, it’s a great idea to seek out a mental health practitioner, such as a psychologist.

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Teschuk agrees with Sygo, and encourages all athletes who are having a hard time finding balance to seek the help of a professional. “My advice to anyone struggling with body shaming and expectations is to focus on what your body can do, rather than how it looks,” she says. “Shortcuts don’t work. Focus on training hard, fuelling and recovering, rather than a number on a scale or your body composition. Healthy and happy athletes are fast athletes, and no race is worth sacrificing your long-term health and performance.”

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