Sylvia, he can open more but again we want to keep it within reason so as not to disturb the abs or the spine too much. If at some point he did not go as far as others then yes that is him not getting enough air in. Just keep your ribcage expanding laterally is the most important point.

Ok understand Cecile. Thanks a million!

Hi Cecile, this has been so informative, assisting me a lot to explain to my class how to do this, always easy to do yourself, but hard to get it across to the class and this helped me a lot. Also helpful were the questions and your answers, thanks a lot for taking the time.

Very useful tips! Thanks!

Thank you for the tips.