So first up in my series of oddball things I've started doing to help me improve my running is nose breathing. As the name says, I do all of my breathing through my nose when I run now (and of course when I'm not running either). An important distinction is that I both inhale and exhale through the nose, rather than the more common "in through nose, out through mouth" or all mouth breathing.
Last winter, I noticed that when the weather got cold, I started getting some mild exercise-induced asthma. It starts with a little tickle in the airway, then moves to light coughing and struggles to get air in, and finally ends up as some nice wheezing and gasping for air. If you've ever experienced even a slight bit of asthma, you know how unpleasant (and dangerous) it is. This seems to happen to a lot of people during the winter, because the cold air both irritates the lungs and also tends to be drier. And of course, the harder your exert yourself, the worse the asthma gets.
I got through that winter okay, but it was bad enough that my PCP and I decided that if it happened again this winter, I might need to get an inhaler. I really didn't want to go down that path, so I started doing some research about alternative therapies. It turns out that there were some small studies published that suggested that nose breathing could help prevent bronchial irritation and improve asthma symptoms. I did some more poking around and found that there were even some oddball runners out there who contend that it's a more efficient way to run for longer distances (something about maintainingg CO2 levels so that your body doesn't feel like it's hyperventilating).
Now, I don't have the time to cite all the sources out there, but there are several purported benefits to nose breathing. Breathing in through the nose allows the air to warm up more before it hits the lung, thus decreasing bronchial irritation. Breathing out through the nose helps keep your breathing even and steady (in cold weather, I've found that it also keeps your nose warm, because if you only breathe in through the nose that means that the nose only gets cold air). Breathing through the nose supposedly has other benefits as well, like increased nitric oxide production in the sinuses (helps dilate your blood vessels and keep your blood pressure down). And the turbinates in your nasal passages help funnel air into the deeper parts of your lung compared to mouth breathing. Finally, your nasal passages are lined with cilia, which help filter particulates out of the air before they hit your lungs.
Figuring I had nothing to lose but an open mind, I decided to give it a shot over the summer, after my spring races were done and before I really had to start training for the fall race.
Okay, so the first thing about nose breathing is that it slows you down at first. It slows you down a lot. In spring of 2009, I ran a half-marathon at an 8:00/mile pace. My "easy" training pace was around 9:15/mile and it was very comfortable. When I first tried to breathe exclusively through my nose, I couldn't even run for more than a quarter of a mile at a 9:30ish pace before I had to open my mouth and gasp for air. So I did as much as I could, slowed down a lot, and just kept putting the miles in.
The real limiting factor is the exhaling part. It seems that when you breathe out through the nose, you really need to use your diaphragm to get the air out. But my diaphragm wasn't strong enough to push the air out as fast as I needed it. There would be a moment where I would really feel the need to start inhaling but I wasn't done with my exhale yet. It was unpleasant to say the least. Eventually, I believe my diaphragm got stronger and my exhale rates increased - either that or I just somehow got more aerobically efficient and required less oxygen. It's probably a combination of both. At any rate, after about a month, I was able to run over 5 miles at my easy pace breathing exclusively through my nose.
Okay, so once I was able to maintain the nose breathing for a few miles, then the question became, will I ever be able to get back to my race paces? One night in August, I decided to open up the throttle and see where I could take it. I did 2 miles at an easy pace of 9:31 to warm up, then I hit it. I ended up running 3 miles at 7:23, 7:16, and 7:13, which were pretty close to the 7:14 pace I had run in a 5K earlier that summer (mouth breathing and dying). And I didn't feel like I was dying this time. I was a convert. But the true test was still to come in the winter.
So now that I'm fully converted to nose breathing, I'm happy to report that this winter I've had no issues with exercise-induced asthma. None! Not even a slight tickle. While most of my runs have been at an easy pace, I've opened it up a few times and had no issues. In fact, just a couple of days ago, I ran a few miles at a sub-7:30 pace in below freezing temperatures - no problems. Now, it may just be that since I'm in better shape than I was last winter, that's what solved the asthma. But the thing is, even if that's the case, nose breathing has become so natural and comfortable for me now that it feels really odd when I try to mouth breathe. So at this point, I really have no reason to change back.
There are only two downsides that I've discovered so far. First is that I generally need to blow my nose about a mile into my run when it's really cold out - so I have to keep tissues handy because I'm pretty bad at the farmer's blow. Second, nose breathing is definitely noisier. It doesn't bother me at all, but sometimes other runners think I'm really struggling when I'm actually running at a really comfortable and easy pace. I'd like to say that I don't really care what they think, but I definitely feel self-conscious about it for some reason.
There is plenty of information out there on the interweb about nose breathing. I don't know how much of it is true, but if you look on Pubmed, you'll find some actual published studies on it. And there was a Russian scientist, Konstantin Buteyko, who has created a breathing program to help asthma sufferers. I don't really know anything about it (so don't take it as an endorsement), but it got some press in the NYTimes recently. If you suffer from asthma, it might be worth checking out. Oh, and final disclaimer - I'm not a doctor and I don't pretend to be one on TV. Nothing here should be construed as medical advice - it's merely meant to be informative. Please consult your physician and do your own research if you are interested in controlling asthma. Good luck!