It is easy for the suppressed mind to take anything in, but to release it is difficult. So a suppressed mind will become constipated in a way. Everything will be taken in and nothing will be thrown out.
The body will begin to be greedy, it will begin to accumulate. Even the excreta cannot be thrown out.
For this type of mind, the breath cannot be thrown out so easily.
It is good to start with the body, it is necessary. But it is not sufficient. There are many problems with Hatha Yoga particularly for those in the West, because the system of Hatha Yoga and its related techniques were all developed in a very different milieu – really, for very differently constituted bodies as well as for different minds.