If you feel short of breath or get side stitches often while you’re running one problem you may be having is that you’re taking shallow breaths using your chest rather than using your diaphragm. If you can use your diaphragm muscle to pull down and help to fully fill your lungs, you’ll get better oxygen exchange and run more efficiently.
Now how do you do this?
The key is knowing that when you breathe in deeply your abdomen should go out to the front and out to the sides. Your chest should not expand more than your stomach during inhalation. Most of us are trained throughout our life to suck in our stomach and stick out our chest. However, that is an ineffective way to breathe during running.
Try this: put one hand on your chest and one hand on your belly or abdomen. When you breathe in deeply through your nose (or mouth) you should feel the hand on your abdomen go out and then when you exhale out of your mouth your hand should go back in.
Practice for a while in sitting and then standing and walking before you try it during running. You may need to try it while you’re running during slower runs or occasionally reset your breathing when you hit every mile marker to slowly change this breathing pattern into a habit.
This is also a great technique if you feel anxious or have difficulty taking full breaths during stressful situations.
Let me know how it goes!