This happens a lot and most of my clients are always super embarrassed when I get them to do a burpee and they burp. They shouldn’t be embarrassed and neither should you. Burping during exercise is completely natural and uncontrollable. The easiest way to explain burping when you exercise is to compare it to the shaking of a pop bottle.
We all carry gasses in our stomach and when we bounce up \and down and make sudden movements what we do it shake up the “carbonation” and the gas has to be realised. So that would mean you could be eating foods that cause excess gas in your stomach. Most foods that contain carbohydrates can cause gas,sugars and starches in any form are the worst contributors. Fats and proteins cause little gas.
Another reason could be that when you exercise and are out of breath, you swallow too much air in an attempt to get oxygen, having excess air in your stomach causes you to burp.
So there you have it!! Dont be embarrassed its a natural thing.