How Vegan Diets Affect Your Workouts

During Tuesday's blowout record-breaking World Cup game, U.S. forward, Alex Morgan, scored five goals, helping the U.S. Women's National Team clinch the victory 13-0 over Thailand. Morgan is definitely one of the stars to watch this World Cup. Whether you're a soccer player or just an awe-struck spectator, you might be wondering how on earth Morgan accomplishes these superhuman feats.

Of course, professional athletes have highly specific training routines that allow them to perform at their peak potential. But in a recent interview with Time, Morgan revealed that switching to a vegan diet has been key to her success on the field. She first adopted a vegan diet, "because it didn’t feel fair to have a dog I adore, and yet eat meat all the time," she told Reuters. She soon discovered that eating a plant-based diet improved her energy during practice and games.

Morgan certainly isn't the first high-profile athlete to praise a vegan diet; everyone from Venus Williams to Colin Kaepernick have spoken about the so-called benefits before. But is this a side effect of the overall trend toward veganism, or could going vegan actually help your workout routine?

Currently, no research has shown that vegan or vegetarian eating patterns improve athletic performance compared to omnivorous eating, explains Tanya Halliday, PhD, professor in the department of health, kinesiology, and recreation at the University of Utah. "Importantly though, they do not appear to decrease athletic performance either," she adds.

We know that athletes who exercise at a very high intensity, often multiple times a day, require more calories (aka energy), carbohydrates, protein, and fat to support their training loads, Dr Halliday says. The specific amount that a given person needs, as well as when they eat, can depend on the type of activity they're doing, and the level of their activity, she adds. A strict dietary pattern, such as a vegan diet, obviously limits your food choices, which can make it challenging, she says.

"Cutting out whole food groups eliminates potential sources of nutrients found within those foods," explains Jason Machowsky, RD, CSSD, RCEP, CSCS, board certified sports dietician and exercise physiologist at the Hospital for Special Surgery. "So, it becomes especially important that people who choose to restrict food groups for personal or health reasons seek out those nutrients in the foods that they choose to eat." That might mean making an effort to eat small protein-packed snacks throughout the day, consuming fruits and vegetables with two meals per day, and hydrating to replace lost fluids from a day of training, he adds. "Endurance athletes who train hard should not avoid simple sugars and electrolytes around training times," he says.

If you're curious about whether going vegan could result in similar performance benefits for your own workouts, then Dr. Halliday suggests first examining your reasons for going vegan. In Morgan's case, she said she went vegan for ethical reasons, which many people do. "If the reasons are solely to improve performance or in an effort to lose weight by limiting types of foods — and therefore total calories — consumed, then a vegan diet is probably not appropriate," Dr. Halliday says. Also, consider how reliant you currently are on animal products. "Identify replacement meals without animal products, which still meet nutrient needs," she suggests.

For athletes contemplating a vegan lifestyle, it's important to work with a registered dietitian (one who is certified as a specialist in sports dietetics, aka "CSSD," is ideal), who can collaboratively develop a meal plan that is vegan and supports overall health and athletic performance, Dr. Halliday says. Additionally, it's a good idea to schedule a checkup with your primary care physician or healthcare provider about three to six months after making the change, to make sure your body is handling it well internally, Machowsky says. "I would suggest seeing your physician again a year later, as well, as some nutrient deficiencies can take longer periods of time to reveal themselves." And if you have a big race or game coming up — like, say, the World Cup — then you might want to wait until after to make the lifestyle switch, Dr. Halliday says.

At the end of the day, the key to Morgan's success is much more complicated than just the particular diet she eats. "When athletes believe a certain eating pattern is the cause of improved performance, it is likely more do to a combination of a greater focus placed on nutrition as well as a solid training program," Dr. Halliday says. For example, paying attention to your diet might make you aware of meal timing around training and competitions, proper fueling during training and competition, recovery nutrition, and general healthful eating habits, she says. Those are all good things to think about that don't require a restrictive diet, either.

And, given how Morgan has shined this World Cup, we have a feeling she'd still slay regardless of what she eats.