SMITHFIELD, Cache County — It was the evening of May 8, and Michael McKnight had just come home after a long run — a really long run. In fact, it was a 100-mile run that took him approximately 18 hours and 40 minutes to complete.
When he returned to his wife and two young children at their Smithfield home, he was a little hungry. That’s to be expected, especially since he consumed zero calories the entire run.
But if you were to ask McKnight, the whole endeavor was actually quite enjoyable and uneventful — even bordering on easy.
To understand how one is able to complete such a feat, it is important to add a little backstory, which, in this case, is both figurative and literal.
In 2012, McKnight was out skiing when he hit a jump wrong and landed on his back on a sheet of ice. The resulting injury would require two rods going up his spine and nine screws in his vertebrae to put his back in place. He was also given a bleak prognosis regarding any physical activity, let alone running.
Being 22 years old at the time, McKnight had a future ahead of him that he wanted to fill with doing things he loved. Driven to show that he wasn’t broken, McKnight began running just a few weeks after surgery. Three weeks after that, he ran a 10K, then it was a half marathon. Just over a year after his accident, he completed his first trail ultramarathon, a 28-mile race in Logan.
McKnight, who grew up exploring the Bear River Mountain Range, took easily to the sport of trail and ultrarunning and decided to push his limits even farther. He entered in 50-, 100-, and then 200-mile races. Not only was he able to complete the distances, but he began to win and set records.
Pushing more limits
Pushing limits soon became second nature for McKnight, and he wanted to see what his body was really capable of. There were a couple of things that were setting him back from competing at his peak level: his weight and trouble with digestion.
"I am on the heavier side for an ultrarunner, and my weight was around 190 pounds," McKnight said. "I also struggled with keeping food down during runs and races. I wanted to explore different things that might help me slim down and fix my digestive issues. I heard about the keto diet, and fat-adapted athletes, and thought I would give it a try. I’ve been living a keto lifestyle for three years, and it’s worked out really well for me."
The kenetic (keto) diet, in a nutshell, operates on the premise that your body can burn fat instead of carbs (glucose) for energy. According to Healthline, after a few days a diet very low in carbs and high in fat, puts your body in ketosis, which is a metabolic state in which fatty acids are broken down to form ketone bodies for energy.
There are varied ways to observe a keto diet, and varied degrees of observance. McKnight has become what is called a fat adapted athlete, which, also according to Healthline, means that your body has reached a state in which it more effectively burns fat for energy.
I fast for 18 hours a day and allow myself to eat between the hours of 1 p.m. and 7 p.m. I eat mostly a carnivore diet of steak, eggs and bacon, and have fruit to replenish the glycogen I lose when running. I've felt a positive difference in how efficient my body works while running and in everyday life.
–Michael McKnight, ultramarathoner
McKnight, who also coaches professionally, said that this lifestyle has helped him train and race more efficiently because it allows his body to burn through fat stores rather than relying on carbs before and during his runs. He said that while he isn't encouraging everyone to practice a keto diet, soon after he adopted the keto lifestyle he was able to shed the pounds he needed and the digestive issues that plagued him before were no longer a problem.
"I fast for 18 hours a day and allow myself to eat between the hours of 1 p.m. and 7 p.m.," he said. "I eat mostly a carnivore diet of steak, eggs and bacon, and have fruit to replenish the glycogen I lose when running. I've felt a positive difference in how efficient my body works while running and in everyday life."
Taking on another challenge
In October of 2019, McKnight had the breakout race of his career, which actually consisted of three 200-mile races. The event is known as the Triple Crown of 200’s, where runners complete three 200-mile races in the space of eight weeks. McKnight won each of the three races and set records in each race.
Fueled with the success of that event, McKnight was looking forward to another great racing season. Then the COVID-19 pandemic hit, and all of his spring races were canceled. With a body that was trained and ready to accomplish great things, McKnight decided that it was as good a time as any to combine his keto lifestyle with ultrarunning in what many were calling the unthinkable.
"I had done several of my longer runs while fasting," McKnight said. "I had done some 20-mile runs and ran up to 32 miles with no calories, and I felt just fine. Running 100 miles without calories would definitely be a challenge, but I felt like I had prepared myself really well to be able to do it."
The calorie-free 100-mile journey
In order to reach his goal, McKnight needed to eliminate a lot of things that would waste unnecessary calories. Lots of hills, carrying around too much water, and running a route he wasn’t used to with the possibility of getting lost, were some of those things. With all that in mind, McKnight planned out his run.
"I chose a course that began and ended at my house," he said. "I usually run a lot of steep mountain terrain but knew that I couldn’t do a lot of that. I didn’t want to stay away from the mountain trails, so I made sure that all the hills were at the start of my run because I knew that having them at the end when my legs were dead, would make it hard to finish. I ran on flat, dirt roads and paved country roads. I ran past my old elementary school and high school, and my parents’ house. I saw some of my old teachers who cheered for me. I even ran past the cemetery where my grandparents were buried."
"I made sure that there were places where I could refill my water, or be close enough to call my wife if I was running low," he said. "I had a bag of salt and potassium for electrolytes to help my muscles and water retention. There were no calories in any of those. It feels strange to say that it was really just an uneventful, nice run."
McKnight said that since the run, he has wondered why it felt so easy.
"There wasn’t a time when I ever felt like I was struggling or was even all that hungry, and I have recovered really well," McKnight said. "I know I prepared well with my physical and nutritional training, but I have been wondering why it was as easy as it was."
Photographer and friend Matthew Van Horn took pictures of McKnight during his 100-mile, zero-calorie endeavor. Van Horn followed him for several miles and said he observed something that he believes was key to McKnight’s success that day.
"I have studied the keto diet and fat-adaptiveness for a while, and there really is something there," he said. "But watching Mike running in his hometown, you could tell he was very comfortable. We passed his old church, and he pointed and said, ‘That’s the church I went to growing up.’ We passed his old school. We even stopped by his parents’ house for a short rest to get some water, and Mike’s dad showed us his collection of cars he’d restored including Mike’s old mustang."
Van Horn, who is an accomplished ultrarunner in his own right, said that there was a certain comfort that he observed, and said that perhaps it was the comfort of the familiarities of home that helped McKnight make it through what should have been such a challenge.
Food is a necessity, but it is also a comfort. We often eat when we’re happy, sad, or when we’re bored. I believe that Mike was physically prepared, but the comfort he felt in his hometown surrounded by those he loved, in a way, replaced his need to be comforted by food.
–Matthew Van Horn, Michael McKnight's friend & photographer
"Food is a necessity, but it is also a comfort," Van Horn said. "We often eat when we’re happy, sad, or when we’re bored. I believe that Mike was physically prepared, but the comfort he felt in his hometown surrounded by those he loved, in a way, replaced his need to be comforted by food."
When presented with the theory, McKnight agreed.
"I've been trying to figure out why this felt so much easier than I projected," he said. "I felt very comfortable. Being able to see friends, family and familiar places was very peaceful. I had the route downloaded to my watch, but I really didn't need it. I'm 30 years old and have lived in this small valley for 28 of those years."
What's next for McKnight?
If all goes as planned, he hopes to run Badwater, a 135-mile course in California's Death Valley, this coming July. For that one, he says he will have some calories with him along the way.