The Long Run

Why our bodies are built for endurance sports, even as we age.

author : Erin Schumaker

art : John Francis Peters

In the endurance-infused world of ultramarathoning, Pamela Reed is the stuff of legends.

Reed, age 58, estimates that she’s run more than 80 marathons over the course of her 40-year running career, including all the big ones, like London, New York, Chicago, and Boston. Her biggest claim to fame: Her back-to-back wins in the 135-mile (217 km) Badwater Ultramarathon in 2002 and 2003, where she not only set a record on the women’s course, but also beat all of her male competitors across the finish line.

In April, Reed hit the trails again, to com- pete in Zion National Park, Utah’s 100-mile ultramarathon. Reed placed third among the female finishers and crossed the finish line less than 10 minutes after the top male contender. Still, it was a challenging race, even for Reed. Up in the mountains, temperatures plunged below 30 degrees and by 2:30 in the morning, it was dark, and Reed was freezing. Her mood black- ened. All she could think about was getting back to her car and turning on the heat, she explains.

“I faltered on my positivity,” Reed says. “I’ve got to work harder on that next time.”

“Is there something about women that makes them better suited to this kind of distance running than men?” David Letterman asked her in 2003, when Reed appeared on his late night show after winning Badwater outright for the second con- secutive year.

“Maybe because we have more fat on us?” Reed posited. “Or maybe because we’re able to have children, mentally we can go through a lot of pain. There’s definitely pain involved.”

Are women really better suited to distance running, as Letterman suggested? Yes and no, exercise physiologists and running coaches say. Women’s hormones can give them an advantage in endurance running that they don’t have in power-based running competitions, like sprinting.

“Estrogen is a very endurance-friendly hormone,” says Jason Karp, an exercise physiologist and co-author of the book Running for Women, who has coached hundreds of runners over the course of his career. “Women are typically better at using fat and conserving their limited store of carbohydrates compared to men.” Exactly why estrogen triggers women’s bodies to rely on fat, however, is a bit of a mystery.

Pamela Reed in Utah the day before Zion National Park’s 100-mile ultramarathon, where she placed third among female finishers in April.
Pamela Reed in Utah the day before Zion National Park’s 100-mile ultramarathon, where she placed third among female finishers in April.

That advantage could help explain why female and male marathon and ultramarathon winners are much closer competitors than female and male sprinters, Karp says.

“Between 100 meters and the marathon, there’s about a 10 percent difference between the best men and the best women,” Karp explains. “When you get into ultramarathons, that difference shrinks.” Indeed, in the case of Reed’s first-place overall finishes, that difference disappeared altogether.


Regardless of gender, all runners eventually slow down as they age. In part, this has to do with changes in skeletal muscle fibers as humans get older, which can be divided into two types: slow-twitch and fast-twitch.

“Both men and women are born with a certain percentage of slow-twitch and fast-twitch muscle fibers,” Karp says. Slow-twitch muscle fibers, which are also known as Type 1 fibers, are the type you use for everyday activities like standing, walking, and climbing stairs, while fast-twitch, or Type 2 fibers, only get recruited during powerful movements, like heavy strength training or sprinting.

As men and women age, especially once they pass 50, they tend to lose muscle mass as a part of a process called sarcopenia, according to Peter Tiidus, dean of applied health sciences at Brock University in Ontario, Canada. “You tend to preferentially lose more of the so-called fast- twitch muscle fibers than the slow-twitch muscle fibers as you age,” he says.

Unlike muscle atrophy, which occurs when a muscle is immobilized (binding an arm in a cast after an injury, for example), sarcopenia “is essentially selective cell death,” Tiidus says.


Reed stretches and practices yoga in the desert near Zion National Park the day before the ultramarathon.
Reed stretches and practices yoga in the desert near Zion National Park the day before the ultramarathon.


That’s not to say athletes should resign themselves to slowing down once they hit middle age.

“Strength loss, balance loss, it’s all preventable through training,” says Chris Kolba, a sports medicine physical therapist and strength and conditioning specialist at the Ohio State University’s Wexner Medical Center. “You’re not going to counter aging, but you can significantly change the course of your ability to function, whether that be in life or on the road for running.”

Cross training is particularly important for older endurance athletes like Reed, who, in addition to daily runs, rides a stationary bike, swims, goes cross-country skiing, and practices hot yoga.

Reed’s diverse workout routine, which mixes strength and endurance training, is a useful blueprint for female distance runners, who are particularly at risk for osteoporosis in the hips, wrists, and shoulders as they age, a condition that can lead to injuries that derail training.

I’m not joking when I say that I hope I drop dead on a trail, or on a road, running.

Hormonal changes during menopause, including plummeting estrogen levels, further exacerbate women’s osteoporosis risk. Women’s long-distance running performance can also wane during this time period.

“Once women go through menopause and don’t have estrogen, their endurance really drops off,” Karp says.

With the right mix of endurance and strength training, women can maintain or even improve their distance performance as they age, up to a point. As the fast-twitch muscle fibers die off, the slow-twitch muscles become more dominant.

“We lose speed faster than we lose endurance,” Karp says, noting that endurance runners typically perform at higher levels, at slightly older ages, compared with sprinters. “The best sprinters are typically in their mid-20s,” he says. “The best distance runners typically are late 20s or early 30s.”

For Reed, that peak came even later in life. “My best best running was from 40 to 42,” she says. “That’s when I broke three hours in a marathon and won overall.”

As long as older women are continuing to strength train with weight-bearing exercises, which can improve bone density and ward off potential stress fractures, Karp says distance running should be considered a lifelong sport for women. It’s a philosophy Reed wholeheartedly subscribes to.

“That’s who I am. It’s like brushing my teeth,” she says. “I’m not joking when I say that I hope I drop dead on a trail, or on a road, running. My goal is to be in my 70s and do a 100-mile run.”