Usually IMST training is done with a device that adds resistance to your breathing. If you want to try it without a device, just restrict airflow through your

Usually IMST training is done with a device that adds resistance to your breathing. If you want to try it without a device, just restrict airflow through your nostrils with your thumbs while inhaling. (and keep your mouth closed of course). It should be very difficult to inhale. You exhale freely