The floor of the chest cavity is??

The diaphragm, located below the lungs, is the major muscle of respiration. It is a large, dome-shaped muscle that contracts rhythmically and continually, and most of the time, involuntarily. Upon inhalation, the diaphragm contracts and flattens and the chest cavity enlarges.May 16, 2019

take a break move to stretching and slowly work back into physically exercising if the problem continues go to a doctor or physical therapist