Has anyone heard of this concept before / care to shed some light on it?

In this video Dr Cassar basically explains that it helps build your energy, leaving you invigorated after exercise rather than tired. You do it by taking deep, long, controlled inhales and exhales - through your nose only. Running, walking, cycling, whatever cardio, but only through your nose.

I had a look at this before on google too and everywhere it seems to boast benefits of nose-breathing over mouth-breathing, basically because the nose filters more toxins in the air out. I haven't looked more into the Chi part though.

My main exercise these days is beach running, and I've tried this before. At the end of my run I am no longer exhausted or gasping for air, and I seem to have a lot more control during my run and have a steadier pace. I breath in for 4 strides, then out for 4. I do however probably run at a slightly slower pace (however i've only done this for the full duration of my run - 30 minutes - once), but i'm sure that would improve over time. Initially it felt like I was underwater or something, that feeling of oxygen depravity, but after awhile you kind of get used to it and I think due to this feeling, your body and all its functions has to therefore run more efficiently.

Heres the video that talks about Chi Breathing:

https://www.youtube.com/watch?v=K0PzDy_hyKY

Thoughts / opinions: Wanted!