I have often been asked about breathing techniques for runners and it’s an interesting question. My initial response is that obviously you need to breathe properly while you’re running, but having said that, I do also think that people can over think it.
Your body is an incredible piece of equipment and your breathing is automatic, so you will breathe as fast or slow as is necessary. The speed of your breathing is controlled by how much oxygen your body needs depending on the intensity of the activity you're doing. However that said, if you are finding that breathing is hard when you’re running and that no matter how quickly you're breathing, it feels like you can't get enough air, it might be an idea to consult a doctor and rule out possible causes like asthma.
The speed of your breathing is controlled by how much oxygen your body needs depending on the intensity of the activity you're doing.
In basic terms if you are out for an easy run you should be able to hold a conversation while running. If you can’t do that it means you’re probably running too fast for your current fitness level. If you are racing or doing some sort of speed session then that is a different matter, because for those sessions you should be working so hard you won’t be able to talk at the same time!
Focus on something else
Often when you are running and breathing really hard it can be a distraction and lead you to think that you are more tired than you actually are. The best thing to do is ignore this completely and focus on something else. As I said your breathing is instinctive and you don't really need to do anything to control it. This is why I find it hard to answer the question "How should I breathe while running?"
I really think it’s a good idea to try and relax as much as possible and just let your body breathe for you, even if you need to slow down to get your breathing under control. I find that breathing in through the mouth and then out through the nose is a good way to get things under control. Not necessarily for the whole run, but just long enough to get back to a stage where you are comfortable. For the duration of the run you should be breathing in through the mouth, because that is the best way to get as much oxygen into your system as possible.
Match your breathing with your strides
Another good way to get things under control is to match your breathing with your strides. For example try inhaling for 2/3 strides and then exhaling for 2/3 strides, although bear in mind the number of stride for each interval depends entirely on how big your lungs are. The more exercise you do though, the more efficient your lungs will become and your body will adapt and increase the amount of oxygen you can take in with each breath. I'm basically saying that the more running you do, the better and more efficient your breathing will be.
Have good posture
To help matters you need to make sure that your posture is good and that you’re not slouching while you run. If you are it will really limit the amount of air you can get into the lungs. I often see runners hunched over and really struggling while they’re running but if they weren't hunched over as much, they'd find it a lot easier! Obviously you don't want to be over exaggerating and leaning back while running and pushing your chest out, but just be sensible and don't slouch! You can get into the habit of focusing on good posture when sitting in the office or at home by practicing with your shoulders back and chest out!