OSLO, NORWAY – It’s a well known fact that cross-country skiing is among the worst offenders when it comes to increasing risk of exercise induced asthma and has some of the highest use of asthma medicine among elite athletes.
According to the Norwegian TV station NRK, as many as half of the skiers on the Norwegian national team have asthma.
“These are not exact numbers, but we test the national team every year, and about half of them show sure signs of asthma,” says Kai-Håkon Carlsen, professor at the Norwegian College of Exercise Science (NIH).
Cold and stress to blame
Brutal competitions and training in at times extreme cold is part of the reason why so many cross-country skiers suffer from asthma.
“Asthma is particularly prevalent in cross-country skiers. The longer an athlete is pursuing the sport, the higher the risk of developing asthma problems,” the expert says to NRK.
“Events such as Tour de Ski where the athletes have several events back to back put extreme stress on the airways,” Carlsen explains.
Athletes who develop asthma through extreme training also put themselves as increased risk of other health problems. “A regular physician would suggest these patients reduce their stress level. But for these athletes, their training is the most important pursuit in the world. And they have to train that way in order to perform and produce the results they expect,” Carlsen says.
From www.langrenn.com, August 5, 2010 (Source: www.nrk.no.) Translation by Inge Scheve
Inge Scheve
Inge is FasterSkier's international reporter, born and bred in Norway. A cross-country ski racer and mountain runner, she also dabbles on two wheels in the offseason. If it's steep and long, she loves it. Follow her on Twitter: @IngeScheve.
14 comments
pleonard
August 12, 2010 at 3:36 pm
Living, skiing and coaching in Fairbanks, AK, articles like this one really irritate me because they fail to really address what the mechanism for development of asthma actually is, instead they look at a population of athletes notice a higher than normal incidence and say ‘skiing in the cold is bad for you’ or some such half truth. Without any experience in training and coaching in the extreme cold, I might read this article and think that any time it got cold we need to huddle indoors in fear of ‘the cold’ as if it is some sort of monster lurking outdoors ready to rob us of our ability to breathe.
From my observations as a coach and from the reading I have done on the subject the culprit is not actually ‘cold’ but low humidity in the air – due to its low temperature, air simply cannot hold enough moisture. By the time the air reaches the lungs it is at or very close to body temperature. In a healthy individual breathing clean, pollution-free air low humidity air is not a problem – they may experience temporary discomfort, or coughing after a hard effort (but that can happen at 40F too) if they breathe the air directly, but no lasting effect. However, if an individual has or is recovering from a respiratory infection or the air is highly polluted and they train outside in very low-humidity air without any shield (airtrim/lungplus/balaclava/facemask/neck warmer) then they greatly increase their risk for developing asthma. Over the past 4 winters here, I can point to more than a couple of occasions where athletes have not given themselves adequate time to recover from respiratory illness and ended up developing breathing issues. I can also point to many life-long skiers who have never had an issue despite regularly skiing in sub-zero (F) temperatures.
The one statement I find interesting here is Dr. Carlsen’s mention of the increased irritation from back to back hard efforts in the Tour de Ski. Again, as with any of the rest of this, I am skeptical due to the reading (some of which I believe was referenced here on FasterSkier a couple of years ago and might be good to link on this article to give a balanced appraisal of the subject) I have done and observations I have made as a coach and skier in the cold, and would want to see some peer-reviewed data that actually indicates this rather than comments or population studies that make good headlines but spread half truths as to what is actually happening.
Additionally, I feel that publishing articles like this does our sport little good and only adds to the public hysteria about skiing at cold temperatures. There is already enough of that in Norway and I have read that there have been calls from some folks there to change the FIS temp cutoff to something like -12C/10F or -15C/5F, which would virtually erase the opportunity for races using this cutoff in certain parts of the world – and perhaps even areas of Norway which are predicted to cool in certain models of climate change.
tim.whiton
August 12, 2010 at 4:22 pm
I agree with Pete that there is something very important missing in this article. I have been an asthmatic since birth and find articles like this incomplete and too one-sided, like most fasterskier.com articles have been recently. If this is going to be the premier website for cross-country ski journalism why are articles only offering one point of view? In regards to this piece, why not take the next step from simple translation (which does have its benefits, of course) and talk with respected medical practitioners who specialize in treating athletes with asthma.
This article implies that training and racing is making athletes sick and this brings us to the problem Pete is worried about.
Personally, it has been the training and racing for skiing and running that has made me healthier and allowed me to better control my asthma. My doctor gets pissed every June when I go to see her and I haven’t been running or skiing all that much recently: my breathing tests are always way down. I am also currently working with her office on trying to get the younger patients with chronic asthma outside doing strenuous aerobic exercise and one avenue I have been particularly pushing is cross-country skiing in the winter. What better way to grow the sport? But incomplete and one-sided articles like this will scare the crap out of parents and we will lose these potential skiers and the kids will likely continue to struggle with their asthma especially during the winter when skiing is the only outdoor aerobic sport to do.
trski
August 12, 2010 at 5:50 pm
obviously a very poorly written article. It is like saying the sky is blue…. well thanks cap’n obvious … it really is blue. Don’t think i would take it any other way. Having suffered from EIA as a cyclist it is usually exacerbated by the cold, dry air and lack of humidity. An athlete usually ‘grows out of the problem’ as he/she matures. Probably because they are not pushing themselves to the limits they used to because we ALL now have day jobs and real livings to make. Overall, a poorly written article/translation. Moving on to more important matters.
Tim Kelley
August 13, 2010 at 12:08 am
Thanks to Pete for jumping on this classic junk science article. You Fairbanks skiers know the real story. I like how these types of articles talk about World Cup cross country ski racers that only exercise outdoors for relatively short periods of time. It’s ironic that you don’t hear accounts of EIA with skiers that really spend a lot of time exercising in extreme cold, like winter and arctic expedition skiers and ultra-race competitors that put in up to 24 hr per day efforts day after day.
I’ve got to admit – I’m cynical when I hear claims of xc skiers getting EIA asthma after witnessing the “epidemic” of asthma problems with US skiers in the 90’s. Many skiers back then were getting “diagnosed” with asthma so they could get prescriptions for legal inhaler products that they assumed would improve their performance. And it was amazing how their asthma problems quickly were cured and forgotten as soon as the important qualifying races (such as Oly tryouts) were over.
jsasseville
August 13, 2010 at 6:55 am
Not only is this article an example of incomplete science, it also looks like “spin” to me. Last year before the start of the season Marit Bjoergen was given a medical exemption for a banned asthma medication. Her performance after receiving this exemption and using this drug was considerably better than before – she had her best year ever. At the time the coaches on the Norwegian team stated that the drug was not the reason why she was faster, but that she was training better. However, doctors with the team stated that the drug was helping her and did contribute to her success. After all, if a drugged is banned, there must be some positive effect, even for someone who doesn’t need it.
During the Olympics there was a story stating that a much higher proportion than normal of Norwegian National team skiers had EIA than in the normal population. I remember Justina Kowalczyk stating then that in looking at how fast Bjoergen was going at the Olympics that she herself should go to the Polish doctors and get “asthma” so that she could use the same drug.
I can’t help but think that stories like this are being used to give some credibility to all of these skiers using medication to increase their lung function. As an asthmatic who grew up in Winnipeg I agree that exercise helped me to breathe better overall and we raced in temperatures below -20C often.
rbradlee
August 13, 2010 at 9:30 am
I’d just like to follow up on one of Pete’s points. I think a big factor in EIA is air-pollution. I race every week in the winter at Weston Ski Track (where Pete got his start) near Boston. The race course is right next to the junction of two interstate highways (8 lanes each – Rte 90 and 95). The air temperature is usually quite moderate and the humidity reasonable (it’s just a few miles to the ocean). However, after the race I have quite a bad Racer’s Hack. We need to clean up the air, not quit ski racing.
Rob Bradlee
Sven
August 13, 2010 at 9:36 am
This flies in the face of the experience of many of us. I’d be interested to see hard data i.e. pulmonary function tests on the half of the half of the Norwegian national team that claims to have asthma.
-Adam Johnson
pheski
August 13, 2010 at 8:02 pm
As a primary care physician with special interest in sports medicine, a life-long member of the asthma club, and committed to responding to sloppy pseudo-medicine, I have to make some comments:
1. Asthma is a collection of illnesses, not a single condition. Not everyone with asthma has the same etiology, symptoms, triggers, response to treatment, or long term outcomes. For example, the article does not talk about how many of the athletes have allergic rhinitis or allergic asthma. Any article that lumps all asthma patients together is immediately suspect as superficial at best.
2. The article mentions neither how they define EIA nor how they make the diagnosis. These are critical if one is to make claims of high prevalence. Eucapnic voluntary hyperventilation (EVH), symptom scoring, direct chemical challenges (e.g.methacholine), and sport specific challenges all give starkly different prevalence rates – and none of these have been studied well to determine clinical significance as opposed to statistical significance.
3. Current studies suggest that drying and to some degree cooling of the airway mucosa are the trigger(s) that cause reversible airway narrowing in susceptible individuals with EIA. I am aware of no credible literature showing exercise as a cause (rather than a trigger) of asthma. Perhaps this is a translation issue>
4. It is important to recognize that testing that shows airway narrowing is not the same as identifying the clinical disease known as EIA.
5. Since exercise in cold and dry air may trigger EIA in susceptible individuals, the more often and the more intensely one exercises in cold and dry air, the more opportunities one has to observe the trigger. This is NOT evidence of causality. There are more motor vehicles accidents on Friday night than Tuesday morning, but Friday night does not cause accidents – there are simply more cars on the road and more impaired drivers.
6. Prevalence figures in the published literature are all over the map. Probably 10-15% of the general US population have some degree of symptomatic EIA, 95% of allergic asthmatics, 30-40% of patients with allergic rhinitis but not diagnosed with allergic asthma. In athletes, studies have shown prevalences of 10-50%, but without consistent definitions or testing systems, and generally small studies (as low as 14 subjects). Swimmers have a higher incidence of asthma than many sports, not because it causes asthma but because exercise in that environment is better tolerated by asthmatics and fewer quit.
7. Dr. Carlsen needs to also report what test and test criteria they use when screening the team, whether the results remain stable over a 10 year skiing career, what the prevlaence of alleric asthma and rhinitis are in the skiers, and what the baseline prevalences if these conditions are in non-skiers.
The line ‘It’s a well known fact that…’ would not have gotten past my 9th grade English teacher: if it is truly a well known fact, one needn’t say so. If one needs to say this, it usually means it is not well known, and the statement is false.
In short, the article is long on hype and bold statements and short on actual information.
Peter
caldxski
August 14, 2010 at 9:00 am
There’s a wonderful story about the days when the FIS was determining the rules for minimum low temperatures at which a xc race could be held. Back then the strongest countries were Norway, Sweden, Finland and the USSR, and so all eyes were on their representatives as they made comments on the temperatures.
Coincidentally, it happened that these countries were asked their opinions in the geographical (and nearly alphabetical) order listed above, with Finland as Suomi. The Norwegians cited cold temperatures as being harmful (even back then) and suggested a minimum of -15C. The Swedes went along but suggested -16C. The Finns, coming from a colder climate and being more accustomed to it, suggested -17C. Finally, the Russians suggested -21C and said “Skiing is not a tropical sport.”
The Russians summed it up.
John Caldwell
ajohnson
August 14, 2010 at 2:39 pm
Looks like Dr. Carlsen should attend Peter’s Journal Club meetings. Thanks Peter.
adam
nordic_dave
August 14, 2010 at 4:01 pm
You can look at a variety of environmental factors that cause
Either respiratory infections or exercise induced asthma.
Often times the asthma is a result of fighting off a long infection.The immune system is compromised and then susceptible to asthma. Bacterial pnuemonia usually comes with the after effects of asthma which can be treated and cured. I lived through this episode once.
Environmental factors that can contribute to exercise induced
Asthma:
Poor air quality/ pollution.
Dust
Wild fires or chimney smoke with a high
Degree of pm 10
Dry abrasive and cold air
High chemical contents like chlorene saturated in a closed
Air environment like swimming pools.
Poor hvac air circulation systems like indoor
Gyms or office buildings
Net result exercised induced asthma is common in every sport.
The headline to this article is shrill. The point although duly noted as to be precautionary is somewhat mute.
Lawrence
August 25, 2010 at 3:08 pm
One thing that is not much discussed in EIA is magnesium levels. Low magnesium levels are associated with asthma. Athletes can lose a great deal of magnesium through sweating. As someone who had asthma, and had low levels of magnesium, I have long suspected this may be an important factor in EIA. My asthma is gone now that have got my magnesium levels up to normal. I admit there were other factors in my asthma, such as allergies, which I have been able to completely control with magnesium ascorbate (a non-acidic vitamin C, that allowed me to take very large doses), after many years of antihistamines, desensitization shots, etc.
Cloxxki
September 11, 2010 at 6:57 am
Funny, I quit mountainbike racing after catching a athmatic allergy for tree pollen. Getting a salbutamol exemption is not so easy for a lesser connected sub-pro athlete. Not that I’d even want to race and need a banned med.
After a few years I decided to pick up skiing, as at least in the winter time I seem to be on top aerobic form with little training, winning to riders who are well out of my league in the summer time.
Just one sunny day in early June 2003, an extraordinary tough race (my first singlespeed race, among geared riders of my level), I seem to have triggered or caught it. Few days later, I was suffocating nad seeig black snow at merely 130bpm of leisurely trying to ride my bike to work. End of race career, it seemed. Perhaps, the air was indeed very dry that one race, perhaps I should try to get data on it as it seems so pivotal for my health. From lung on wheels to pityful lung patient with a fraction of the VO2.
@Lawrence, fascination on your Mg experiences, thanks for sharing!
dpskier
October 11, 2010 at 1:01 pm
I’m late on this and didn’t really know about the controversy on the banned inhalers at the last olympics. I too have found that aerobic exercise helps with asthma. I took up skiing because that was the time of year that I was healthier. I think that people who have a history of having asthma should be allowed waivers. That being said, they should not be allowed to compete if they are being treated for an asthma flare-up or another condition that requires the use of prednisone (a systemic steroid as opposed to the inhaled steroid). This could cost most of the season. There is a big difference in the effect of the drugs. The inhaled drugs basically allow for normal lung function (albuterol will help normal people a little bit) but the prednisone pills provide a huge performance boost once things quiet down. All of the things that they say about steroids are true. People can “develop” asthma later in life. The truth is that the condition was probably already there. A friend of mine who was an elite skier would always be coughing after a race. Over the years this got worse and worse until she went into see a specialist who put her on asthma medication. She tells me that it has made an amazing difference. The Norwegians may be uncovering conditions that these athletes have had all along. Someone of Marit Bjoergen’s stature should come out an talk about her condition for 2 reasons first to put an end to rumors (not that I think the drug she is taking will provide a boost), and second as an inspiration to others.