Can Colorado athletes overcome altitude and genetics?

For veteran ultra-runner Helen Cospolich, living and training at 9,600 feet isn’t as forgiving now as it once was — or ever was.

At 39 years old, the Breckenridge local of 20 years has been running 50- and 100-mile trail races for 15 years and competing at the elite women’s level for nearly as long. She’s won several women’s titles at the Leadville Trail 100 — a relatively easy race made devious by elevations over 10,000 feet, she says — and she regularly travels the world as part of The North Face Endurance Team for races in every mountain range imaginable: the Hardrock 100 in Silverton, Brazil and Ecuador in South America, the Tour du Mont Blanc in the French Alps, and, this coming September, the Tour de Monte Rosa in the Swiss Alps.

But, after years of racing and recovering at extreme altitude — anything above 9,000 feet is considered extreme in the endurance world — the Boulder native has started to notice a change. The ultras take more of a toll than ever before, and she just can’t recover the way she once did. Maybe it’s age, she says, but chances are it’s a combination of everything: age, injuries, genetic makeup and, like so many athletes in Breckenridge, her environment.

“I do think that running long distances at altitude has taken its toll over time,” Cospolich says. “It’s really not ideal to live and recover at altitude. I’m more injury prone these days. Recovering takes much longer than at lower altitude and you feel the difference. You might not realize that’s what it is, but you notice it.”

It’s not all in her head. For years, endurance athletes and experts have struggled to find the perfect altitude for training and recovery. The U.S. Olympic Training Center in Colorado Springs sits at an ideal altitude of 6,035 feet — the sweet spot between sea level and high alpine — while Cospolich’s hometown of Boulder (5,430 feet) is a mecca for elite cyclists and triathletes for the same reason. There’s even a medical journal dedicated to the topic, known as High Altitude Medicine and Biology.

Over time, Cospolich and fellow endurance athletes have dove headfirst into the research to perform better — and, with any luck, better than the rest — at high-altitude races like the Leadville 100. But the question remains: How high is too high?

“I think there’s been an idea that training at altitude can be better for racing at altitude, but I think the sports community understands that living and training here (in Breckenridge) is just too high,” Cospolich says, referring to the pro-level athletes who race in events like the Leadville 100 and Breck Epic mountain bike stage race. “We’re just too high to make it effective.”

The oxygen issue

When Cospolich moved to Summit County at 19 years old, she already had an advantage on runners from sea level because she grew up in Boulder. Her body was familiar with altitude, and although a change of nearly 4,000 vertical feet had an immediate impact, it quickly faded.

In other words, Cospolich was predisposed for acclimation, the process any body goes through to overcome the effects of altitude: headache, shortness of breath and other signs of hypoxia, the medical term for less oxygen reaching muscle and other tissue. In the case of a healthy endurance athlete, hypoxia is usually caused by thinner air at higher altitude, where lower atmospheric pressure forces the lungs and heart to work harder for the oxygen the body needs.

“The problem with training at altitude is that you don’t have enough cardiac output,” says Warren Johnson, a Frisco-based cardiologist who’s currently studying the longterm effects of altitude on heart health. “It’s just like your car, unless you have a turbocharger: You just don’t get enough oxygen. We all have to breathe about 15 percent harder, day and night, when we’re at 9,000 feet and above.”

Johnson points to the now-postponed USA Pro Challenge. Last August, the race drew nearly 200 professional cyclists from across the world, guys and gals with experience at the Tour de France and other elite, demanding races. But, after several stages at 8,000 feet and above, even the world’s best struggled with the effects of hypoxia. As early as Stage 2 — the demanding Arapahoe Basin finish at 11,000 feet, with 1,600 vertical feet of climbing in the final four miles alone — several riders dropped from the race altogether, including Yoav Bear with Israel’s Team Cycling Academy and Hector Saez with Caja Rural-Seguros of Spain.

“You saw this with the Pro Challenge guys,” Johnson says. “They would come from the Tour de France and come straight here, and some of them couldn’t tolerate. They couldn’t keep up.”

The altitude advantage

With time, Johnson says the body gets used to the demands of breathing and living and training at altitude. It takes about a month for the body to fully acclimate, after which organs, muscles and other tissues, like lung membranes, begins to slowly change in response to the environment: capillary density increases, meaning the heart can more effectively transport blood, and the mitochondrial density of the blood itself increases to carry more oxygen.

“There are a lot of mechanisms your body uses to adapt,” says Joe Howdyshell, a local high-alpine endurance runner and coach with Summit Endurance Academy.

“The ones that happen the quickest are blood volume and respiration rate. The stuff that takes longer is building red blood cells. Oxygen moves across (membranes) slower, so your body has to figure out how to transport it faster. Your blood volume will increase to boost your blood pressure, and if your pressure increases then the oxygen is shuttled to your muscles faster.”

For seven years, Howdyshell has lived like Cosplich, training and recovering for endurance races above 9,000 feet from his home base in Frisco. And, like Cospolich, he’s noticed that such an extreme altitude has had an effect on his performance in races at lower altitudes.

“For athletes who live here it’s not as simple as just going to a lower elevation and crushing things,” Howdyshell says. “Up here, you’re never able to train the way you can at a lower elevation. The physiological limits are absolute… That means your training pace will be affected and that affects your ability to be fast.”

The two runners have found one way around this: use the mountain environment to their advantage. When Cospolich needs to train for speed but can’t make it to a lower elevation, she heads to a trail with a slight decline, like the, and lets gravity help her find a full, powerful stride. Howdyshell does the same in the Frisco area, along with sets built around 15 seconds of max effort followed by long rest periods.

“You will get tired faster up here, and the second you get tired you aren’t performing to your best strength and speed,” Howdyshell says. “If you keep training without resting you’ll continue to work at a slower speed. It really is all about making sure you get the rest you need between efforts so you get the absolute max out of your training.”

High altitude, shallow genes

Before getting to rest, however, Johnson and other experts get down to the genetic level. Like all traits — hair color, eye color — a person’s ability to acclimate is informed by DNA. In fact, doctors have already isolated the exact gene that comes into play at altitude: HIF1A, or HIF Alpha 1, an indicator for hypoxia.

“If we get hypoxic, the reaction is that the pulmonary pressure constricts,” Johnson explains. “That increases the pulmonary artery and increases the resistance of the pulmonary bed, and that’s where we start to lose to ability to increase your activity level. That’s where the gene, HIF Alpha 1, gets triggered.”

In a recent study, cardiologist Dan Levine took a group of military veterans from Texas and flew them to Colorado, where they went directly to a high school track and ran two miles. The goal was to figure out who can and can’t handle altitude at the genetic level. It helped identify the HIF1A gene and pointed to a major — and unavoidable — hurdle for athletes who’ve lived and trained in Breckenridge for decades: the Summit County gene pool just isn’t deep enough.

“The reason we have that problem is because we, in Summit County, are the youngest gene pool (at altitude) in North America,” Johnson says. “We had about 2,700 people here in Summit County in 1970. Now, we have 30,000. All of us, our genes are coming from the sea level. If we were in Nepal or South America or Ethiopia, those people have several thousand years of time to acclimate, and those people tend to be better acclimated than we are.”

Is altitude training in Breckenridge a war of attrition, then? Not exactly.

“I will say, living and training at this altitude is a huge advantage for something like the Leadville 100,” Cospolich says. “Because the altitude itself in that race makes it so hard — the course isn’t too difficult — it makes a huge impact to live and train up here.”

The trick? For both Howdyshell and Cospolich, staying in race shape comes down to recovery. Both recommend building a training program with plenty of sleep and at least one rest day, with constant activity sprinkled throughout.

“The best thing you can do is spend a lot of time exercising and a lot of time resting,” Howdyshell says. “Make sure you aren’t just resting on a couch. If you do that your body will say, ‘This is normal.’”

The body struggles with altitude no matter what, the athletes and experts agree, but that shouldn’t mean the end of competition, especially in the heart of the Rockies.

“Looking back I think there were a lot of things I could’ve done earlier to be more effective… but it can be hard up here because it’s so beautiful,” Cospolich says. “The culture up here keeps you active all the time. There’s no real downtime. You always want to be enjoying things, so when you have a rest day it’s hard to look outside and force yourself to recover.”

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