A MEDICAL CORRESPONDENT says on the Tight-lacing— “Women breathe so much more by the enlargement of the upper part of the thorax, that moderate support, short of actual compressions, does no harm if applied about the lower part of the female thorax. Of course if circulation is hindered or organs unduly compressed anywhere, harm is done.
The average size of a woman’s waist is about twenty-two inches for a woman about five feet two inches. Some women may have waist as small as seventeen inches, but the breadth of the shoulders bears a direct relation to the size of the waist. ‘In young children the inspiration is almost entirely by the diaphragm, which being highly arched in expiration becomes flatter as it contracts, and descending presses on the abdominal viscera, and pushes forward the front walls of the abdomen.
The movement of the abdominal walls being here more manifest than any other part, it is usual to call this the abdominal mode or type of respiration. In adult men, together with the descent of the diaphragm and the pushing forward of the front wall of the abdomen, the lower part of the chest and the sternum are subject to a wide movement in inspiration.
In women the movement appears less extensive in the lower, and more so in the upper, part of the chest, a mode of breathing to which a greater mobility of the first rib is adapted.’ – Kirke’s Physiology, p.157. MM. Beau and Maissial call the respiration infra costal, in women supra costal, type of respiration. Dr. Hatchinson gives two diagrams showing the different means of expansion of the thorax in men and in women.
Professors Sharpey and Ellis point out in their work on anatomy, p.109, that the process of ossification does not invade the cartilage of the ribs in women till extreme old age, but occurs in adult age in men to a great extent. ‘The first upper ribs in woman have a greater freedom of motion than in men, causing the breast to rise at each inspiration, whereas in men the chest expands more generally, especially at the lower part.‘— Animal Physiology, by John Shea, p. 107.