Ralf Dujmovits and Nancy Hansen

The doors have closed behind Ralf Dujmovits and Nancy Hansen. The so far only German climber who has scaled all 14 eight-thousanders and his Canadian partner moved in a 110-square-meter hypoxia chamber of the German Aerospace Center (DLR) in Cologne on Tuesday. As reported, the two mountaineers are participating in a study conducted by DLR in cooperation with the University of Texas to investigate whether extreme hypoxia can also have a positive side effect for human beings. US researchers from Texas found in two experiments with mice that heart muscle cells devided when the animals were exposed for two weeks to oxygen deficiency corresponding to conditions at 7,000 m. In mice which had previously been triggered myocardial infarctions, cardiac function improved after two weeks of hypoxia.

Medical control around the clock

Monitor in the control room

Ralf and Nancy, both healthy, are the subjects of the pilot study. They are to stay in the hypoxia chamber for about a month. In the first few weeks, acclimatization as on a Himalayan expedition is simulated. The oxygen percentage in the air will be gradually lowered and temporarily increased only twice in between – as if the two climbers would descend again to breathe thicker air. The last two weeks, the 56-year-old German and the 49-year-old Canadian are to  spend in a simulated height of 7,000 meters. The experiment can be stopped at any time in case serious problems arise. A DLR research team monitors Dujmovits’ and Hansen’s state of health around the clock. The daily schedule includes heart and lung function checks, blood and urine tests, fitness checks and so-called “cognition tests”, which check the reaction and perception of the subjects.

Yesterday, I visited the two climbers in their new “home”. That was possible on Wednesday for the last time without breathing mask. After more than half hour in a simulated altitude of about 3,700 meters, I felt a little bit dizzy. I preferred to do the interview with Ralf subsequently in thick air, by phone.

Ralf, you can not get out, there is no daylight, and the oxygen is lowered. That does not sound like a holiday apartment.

Nancy has a pulmonary function test

No, it isn’t a holiday apartment. But we have adjusted ourselves to it over a long period of time. We took it that way. We prepared ourselves mentally for almost nine months. Now we are here and actually feel quite well.

How does the prospect feel of being locked up for weeks and not being able to move to fresh air? That must be almost like torture for a climber.

Not even like that. I have the great privilege that I was allowed to be outside a lot. I do not see a big problem with being inside for five weeks now. We have been asked this frequently. But neither Nancy nor I are very worried that we can not handle it. We both can be very focused on special things. We have agreed to it and accept it as it is.

How did you prepare for this experiment? Have you filled up as much fresh air and nature as possible?

Skiing down to Monte Rosa Hut

We were in Valais for a week. We spent the final two nights on the Gnifetti Hut at 3,700 meters, followed by a night in the winter room of the Capanna Margherita on the Signalkuppe at 4,550 meters. So to say, we had pure nature for us. We were completely alone on the Capanna Margherita for 24 hours. We got up at 6.30 a.m. to enjoy the beautiful sunrise. Then we skied down to the Monte Rosa Hut through best powder snow. We really filled up, had a great time and, of course, a bit of pre-acclimatization too.

What motivates you to participate in this study?

Nancy had in her family environment some cases of heart attacks that ended either deadly or in very difficult recovery. Therefore, motivation for her is really to be able to bring something forward in the field of research. It’s similar with me. My interest in medicine has always been there and will continue. Being able to be possibly part of a new treatment for heart attack patients is a great story.

Maybe it’s also an additional motivation that this “seven-thousander”, which you want to scale, is still unclimbed.

Of course, it’s a bit of a first ascent. (laughs) But it’s not so much this first-time act that motivates us, but rather the support to get a step further in heart attack research.

Nitrogen tank in the DLR outdoor area

Are you also worried, be it mental or physical, when you consider the weeks in the hypoxia chamber?

There was a big unknown we both had a hard time with. It is not so easy to convert the percentage of oxygen in the air to (virtual) altitude. We have to rely on what Jens and Uli (Prof. Jens Tank and Dr. Ulrich Limper from DLR, the heads of the study) had predicted. But here we also have the opportunity to see how the air is composed by means of sensors installed in all rooms. From my feeling, that fits very well. Therefore, the trust that we must have in the team, is absolutely justified. We feel we are really in good hands here.

You are now the first complete day in the hypoxia chamber, at a quasi-altitude of about 3,700 meters. Does it feel different than on a mountain?

Of course, it’s different because the hardness factors such as strong sunlight, wind, cold, storm or snow fall are missing. So, of course, it’s much easier. But the thin air feels as we know it from high altitude – although the height is simulated by reducing the oxygen content. Normally, this percentage is always the same, no matter how high you are. (The hypoxia is caused by the lower pressure with which the oxygen is pressed into the lungs.) Here nitrogen is pumped into the rooms and thus the oxygen percentage decreases.

Do you think that you will learn something about yourself in the next few weeks?

Mobile climbing wall in the living area

I have already learned a lot. There are many, many little things. For example, we trained on the mobile climbing wall yesterday. It was specially set up for us here because we wanted to stay fit while climbing. We immediately noticed that not the lack of power in the arms or fingers will be the limiting factor, but the stamina in the thin air. We underestimated that. If we climb the overhanging part of the wall here, we’ll probably never get to the point where we run out of energy, but we’ll be at the limit in terms of endurance.

Does it help you to get through the whole thing as a couple?

That definitely makes it a lot easier. Yesterday at dinner I briefly imagined what it would be like if I were sitting here alone, maybe watching the news and then going to bed by myself. That would be terrible. You do not have anyone to talk to about what happened during the day. Being able to do this together with your partner is really great. We have a lot to laugh about. But we had also the first difficult moments during the night. Nancy suffered from headache, I had a slight pressure in my head. You talk about it, and then it’s a bit easier again.

Is it a bit like sitting in a base camp in bad weather and not being able to avoid each other?

You can really compare it. I remember for example 2009, when we were stuck in Lhotse Base Camp for three weeks in extremely bad weather and could only switch between our personal tent and the mess tent. It’s not much different here. However, we actually have more space to move, because the rooms here are very spacious. In addition, we have a lot of tasks to do during the day.

Ralf has a ECG

What do you expect, how will you come out of this experiment? As a physical wreck?

That’s the big unknown. We originally planned to go on expedition afterwards and use this extremely good acclimatization. However, cause we have no idea whether we are still fit enough to climb an interesting mountain, we have limited our plans to the Alps. There are e.g. on the south side of Mont Blanc so many high-altitude destinations. If we’re still fit enough, we’d rather go there instead of buying a permit, having to pay a liaison officer in advance, and then maybe having to say: We’re too weak, it’s just not possible.

But it’s also possible that you will be just lazily lying in the sun?

It’s possible too. After the time here in the chamber, the trade fair “Outdoor” will take place in Friedrichshafen. After that we’ll have a bit of time left without obligations. Maybe then we will be lying in the sun.

Ralf Dujmovits (l.) and Nancy Hansen in the still empty DLR living area

This seven-thousander has neither a summit, nor does it offer impressive views. It covers an area of ​​only around 110 square meters – and is located on the grounds of the German Aerospace Center (DLR) in Cologne. A hypoxia chamber within DLR’s medical research lab “:envihab” – the name stands for environment and habitat – will be comfortably furnished in the coming months.

Four weeks in the chamber

In mid-May, Ralf Dujmovits, the only German mountaineer who has climbed all 14 eight-thousanders, and his partner, the Canadian climber Nancy Hansen, will move in there for four weeks. They are taking part in a highly interesting hypoxia study conducted by DLR in cooperation with the University of Texas. The assumption: Although extreme oxygen deficiency threatens life, there could also be a positive effect on the body.

Stronger heart through hypoxia?

Ralf is wired for magnetic resonance imaging (MRI) …

US researchers from Texas found in two experiments with mice that heart muscle cells devided when the animals were exposed for two weeks to oxygen deficiency corresponding to conditions at 7,000 m. In mice which had previously been triggered myocardial infarctions, cardiac function improved after two weeks of hypoxia.

Now it is to be tested whether this effect also occurs in humans. For this purpose, Dujmovits and Hansen, both healthy, will spend two weeks in an oxygen-reduced environment comparable to 7,000 meters above sea level, as subjects of the pilot study. “We expect them as healthy, well-trained subjects to increase their cardiac output as well,” says DLR doctor Ulrich Limper during the first of several preliminary examinations in Cologne. For a further study, an experienced mountaineer is being sought as test person, who has already stayed at heights significantly higher than 7,000 meters and in addition has suffered a heart attack. He too is to spend two weeks in hypoxic conditions – of course only after he has completely recovered from the infarction.

Immediate termination possible

… and prepared for the examination of his brain

Ralf and Nancy first want to pre-acclimatize on the mountains in the Swiss canton of Valais and then go to the hypoxia chamber in Cologne in mid-May. In the first two weeks, the simulated altitude will be increased from 3,000 to 7,000 m by adding nitrogen and thus slowly lowering the oxygen concentration to eight percent (usually it is 21 percent). Over the last two weeks, Dujmovits and Hansen will have to hold out at the equivalent of an altitude of 7,000 m. Unlike in the mountains, however, the air pressure in the chamber remains constant, so that the experiment could be terminated immediately in case of complications.

“Completely crazy”

Blood draw from Nancy

He has done a lot of research and reading on the findings on long-time stay in high altitude, says Ralf Dujmovits: “In addition, my own experience of many nights in series above 7,000 m have led me to believe that the risk is within manageable limits. And if there are any problems, we can at any time press the red button and stop the study.” Nancy Hansen admits she has a queasy feeling. “Of course I am nervous about the risk! It’s completely crazy to live at the equivalent of 7,000 m for two weeks,” says the 49-year-old. “On the other hand, we can leave the study at any point if we feel too unwell. The bigger question for me is whether there will be long-term negative effects.“

Heart attacks in the family

Measuring the lung volume

Dujmovits had started studying medicine as a young man before fully dedicating himself to the mountains. The interest especially in high altitude medicine has remained, says the most successful German high altitude climber. “Being able to contribute to new findings in the field of myocardial infarction research is fascinating as well as exciting. Moreover, I have the opportunity to learn more about my body and its reaction to hypoxia.” Nancy Hansen agrees, adding family reasons for participating in the study: “My father had a massive heart attack 14 years ago. My uncle died of a heart attack. My young nephew has had two, 16-hour open heart surgeries. The topic is really important to me.”

Interesting for earth and space

This also applies to the DLR. “We are not just learning about the limits of the body of highly trained and specialized people who are comparable with pilots or astronauts and can serve as a study model for them, in our case Nancy and Ralf,” says Ulrich Limper, “but we also have the opportunity to improve the treatment of an acute heart disease, what would especially help the patients on earth.”