Is forcing yourself to breathe slowly after strenuous exercise potentially hazardous?

Question

My endurance is pretty lousy, and has been since I was a child. I overheat quickly, and it's not hard for me to get out of breath (it's improving a bit, with me doing running more often). One of the things I started doing several years ago, was forcing myself to not hyper-ventilate when out of breath, but rather keep a steady rhythm, and try to take in and put out more air. Occasionally, this has backfired, with me finding that I need to stop exercising for a bit because I'm greying out from not getting enough oxygen, but usually it's sufficient to breathe steadily during exercise even if I continue to feel like I'm out of breath.

I've read a few articles on competitive breath-holding where they state that the practice of doing it sometimes involves less the ability to get by with less oxygen and more teaching your brain to ignore the warning signs of oxygen deprivation, leading to problems like shallow water black-outs because you feel fine right up until you pass out. Obviously, above water, this is a bit less dangerous (although I do generally try to avoid passing out, and instead cease the exercise, or let myself gulp breath if it comes down to that). That said, is there any danger that I am, like the underwater breath-holders, masking the symptoms instead of improving my condition by forcing myself to breathe slowly?

Answer 1

It depends. Read thoroughly the invitation for this seminar; there is some information about research on this topic.

It seems that what you are doing can be really beneficial, but also it can be pretty dangerous. It depends on lots of factors, some of them strongly individual. I do not think anybody can advise you with this over internet.

If you want to do it correctly, you probably need to be examined by an expert.

Or you can try to continue, very carefully, and measure if this approach helps or not. Or even more carefully — practice it if you do not exercise — try to inhale and exhale reasonably slow for few minutes every day. This exercise should be safe for the most people.

However, do not expect that such an exercises do magic with your "lousy endurance". It would probably need more direct approach. I would suggest this book as a good place to start:

Maffetone, Philip. The big book of endurance training and racing. Skyhorse Publishing, Inc., 2010.

Answer 2

One thing I was taught during my martial arts tenure growing up was to slowly breathe in through the nose (like two or three seconds) and breathe out the mouth (again two or three seconds). This is something that my personal trainer encourages as I exercise nowadays.

However, my fitness level and cardiovascular health are not as good as they were when I was younger. Every time I exercise I at one point feel like I'm not getting enough oxygen doing the slow breathes so I take some "cheater" breathes to get my mind calm down. Then I return to controlled breathing to return to my body to a more normal state or homeostasis. (Bear in mind that this is all anecdotal so take with a grain of salt)

After some time of consistent exercising, your endurance should get better and this feeling of out of breath will decrease more and more. If after several weeks to a couple of months of no improvement, there may be a medical issue and consulting a doctor would be good. Until then, keep hitting the pavement/gym. :)