He started keeping a journal back in the 1980s.
"I bought a separate journal for just running to log what the time of the day it was, what the weather was," Carr said.
More than 40 years later, he has logged over 60,000 running miles.
"Every mile is outdoors. Never been on a treadmill. Never been bit by a dog. Never been hit by a car. And I've never worn any type of headphones. I want to hear nature. I don't want music or podcasts or anything like that," he said.
With hundreds of races under his belt, including 24 marathons, he's gearing up for one of his biggest races yet, an ultramarathon.
"This one is a hundred miler, and it's made for older runners like me," he said.
One of Carr's biggest cheerleaders was his wife of 53 years, Carlye.
"She was very supportive. She didn't run. She was not an athlete or anything, but she always supported or traveled with me," Carr said.
Last year, Tom lost Carlye to Alzheimer's disease.
"Being a caretaker is one of the most difficult jobs in the world. And especially when you have to be a caretaker with someone with Alzheimer's," he said.
Running was Carr's therapy. When volunteers were unable to sit with his wife while he went on his runs, he had to get creative.
"I had her sit on the front porch so I could keep an eye on her. And then this driveway here, my minimum run is five miles a day. So it took me 85 laps on this driveway to get my five miles, and then a way I can still keep an eye on her," Carr told ABC11.
His race comes as growing evidence supports the value of regular physical exercise to prevent Alzheimer's disease. He's hoping to inspire others to hit the road as well.
"Get that heart rate going. My belief is you're never too old." Carr said.
If you want to join him in his effort to fight Alzheimer's, click here.
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