These 2 exercises worked for me. I did this 5 days a week (around 15-30 mins) and it took approx 4 weeks to get to a predominantly nose breathing situation.
1. Jog slowly at a pace that is comfortable while breathing through your nose.
2. Speed up pace until you feel like you will need to breathe through your mouth stay there for 10-20 seconds.
3. Slow your pace back down to where it's comfortable.
4. Adjust your pace up and down between these zones in intervals.
5. Over time increase pace and interval length.
- It's ok to take some mouth breaths as you continue practicing. The goal is to increase % of breathes via nose.
- When you get the hang of that try it while jumping a rope.
Seated breathing exercise, do with shirt off to observe abdominal and chest region while practicing:
1. Sit comfortable, good upright posture.
2. Breathe in fully and hold for 2 seconds.
3. Sip in as much more breathe you can and hold 2 seconds.
4. Sip in the final amount you can and hold for 2-3 seconds.
5. Exhale out fully and hold for 2 seconds.
6. Exhale out tiny bit more and hold for 2 seconds.
7. Exhale out tiny bit more and hold for 2-3 seconds.
8. Repeat from step 2.
- I found this really good to do in a park or in nature.
These two where my main exercises on top of using that in boxing.
- In a fairly short amount of time I was able to get a full lung breathe through the nose easily.
Good luck.