Don Muchow’s doctor calls him a “mutant diabetic superhero.” It’s no wonder, because in the last 12 months, the 56-year-old Plano, Texas athlete has completed feats that even the most healthy person would hardly think to attempt:

Four marathons four days in a row. A full Ironman (2.4-mile swim, 118-mile bike ride, 26.2-mile run). A 100-mile ultra marathon. And, mid-October, the 223-mile Capital to Coast Relay, which he ran solo.

“I’m doing what others do,” Muchow said, “but with one hand tied behind my back checking my blood sugar.”

He’s only the third person in the race’s eight-year history to run all 223 miles himself, and the first Type 1 diabetic to do so. That’s awe-inspiring, because the logistics and planning are almost incomprehensible.

Add to that testing his blood sugar, checking his ever-present continuous glucose monitor, making sure he rests enough and eats enough, and you have a jaw-dropping balancing act, a tightrope of exercise, insulin and diet. One slip, one stumble, and he could die.

Muchow was diagnosed with Type 1 diabetes at age 10. Gym teachers discouraged him from exercising, so he didn’t. But in 2004, 50 pounds overweight and not managing his diabetes well, he developed circulation problems. Blood was leaking into his eye, a condition called retinopathy, and he underwent a treatment to cauterize the leaking vessels and prevent retina detachment. It was a wake-up call, leading to his determination to start taking care of himself.

How he got started

His first race was a 5K his wife, Leslie Nolen, had signed up for. It took him about an hour to go those 3.1 miles. He completed a half marathon in 2009, a full in 2011, a 50K in 2013. So what else for a diabetic superhero to do but an Ironman, quadruple marathon, the 100-mile ultra and then Capital to Coast? Three years ago, he completed the 223-mile race from Austin, Texas to Corpus Christi, Texas as part of a relay team whose runners all have diabetes.

This year though, it was his alone. His and, he hastens to add, his crew’s: Nolen, his crew chief; Angie Wagner, navigator and driver; and Josh Fabian, a fellow Type 1 who has run 300-mile events by himself and was Muchow’s pacer for half the event.

His race strategy began as jottings on an index card with the names of the towns he’d go through. It ended up as a “massive spreadsheet,” he says. “Every minute was planned.”

Figured in were rest breaks (every 3 to 4 miles until Nolen determined they needed to be less often to ensure Muchow would finish the race before the cutoff time); sleep breaks (sometimes 10 minutes, sometimes 90; never more than three hours); how often he’d monitor his blood sugar. He does this two ways: viewing the readings of his continuous glucose monitor or manually testing with a glucose meter (i.e. a finger prick). If he needs more insulin, he delivers it from his insulin pump through an infusion port in his abdomen.

And then there’s the matter of eating:

“Normally, with an active Type 1 working out an hour or more, you’re sensitive to insulin. All you get goes toward storing energy from food and making it available to the muscles. That means I need to eat more to replace what I’m burning, and every little bit of insulin I take is multiplied in its effect.”

Such stressors as heat, blisters, exhaustion, he says, can have “a tremendous effect on blood sugar in the opposite direction. More insulin won’t help because your body tries to use it to store energy, and that same body is screaming for more energy to be un-stored.”

Fuel required

Fuel breaks were, by necessity, every 3 miles. During 88 hours on the road, he lost 7 pounds, burned 20,000 calories, drank 20 gallons of water or Gatorade and downed 35 cups of pudding, yogurt, mandarin oranges and peaches.

He stopped once at a Dairy Queen, once at Whataburger for the junior cheeseburger combo with onion rings, ranch dressing and ketchup. According to one of his lists, he thought about both fast-food restaurants an estimated 70 times. (Did we mention he keeps meticulous records?)

The longest, most difficult time periods were the 10:30 p.m. till dawn segments, when roads are iffy and dark. He wore a lighted vest and a headlamp. At times he was so exhausted that if he stood still, he’d fall asleep on his feet. Predawn on Day 3, he was weary, limping, needing some pudding and Gatorade. “I saw a guardrail and decided to go sit on it,” he says. “Then it turned into plywood boxes. Then it turned into a fire ant bed. I was hallucinating.”

At one point, another relay team van drove by and offered two of its runners, who had finished their relay segments, to pace him. They were members of Team Diabadass, a team of diabetic relay runners Muchow had put together a few years ago.

“One kept me awake; another made me think about something besides the heat,” Muchow says. “Every time I leaned to one side” (from exhaustion), “they’d push me back.” He could tell when his blood sugar levels were low by his stride, which would get “floppy.”

He’d trained so long and so hard, he recognized the signs. But, as he explains, he had an “almost primal urge to complete what I started.”

During those three-plus days, Muchow may have questioned whether he’d reach the finish line by the designated time. But, he says, “there was never a time physically I didn’t think I’d make it.”

His first food after crossing the finish line was fried fish. Then it was meat: “I ate a lot of beef, eggs, chicken, barbecue.” He also slept 12 to 14 hours at a time, often dreaming he didn’t finish the race. But then he’d see his medal, his four pairs of worn-tread shoes, his broad-brimmed hat, his sunglasses, that beautiful finisher’s sign.

“Looking over my shoulder,” he said, “I acknowledge this is an accomplishment.”

So, as everyone else has been asking him, what’s next?

His plan is to be the first Type 1 to run the Vol State 500, a race diagonally across Tennessee. If that goes well, next up would be running across the United States in 2020, the year he turns 60.

“Every step of the way,” he writes in an email, “I’ve learned more. About what I didn’t know about running. About what only a few dozen Type 1 ultra endurance runners know about the interaction of Type 1 diabetes and stress. And about the amazing elasticity of the human spirit.”