Primum Sapienti
2024-02-05 21:35:58 UTC
From 1967
Quite a number of interesting facts.
http://userhome.brooklyn.cuny.edu/anthro/jbeatty/CORESEA/AMA.pdf
The Diving Women of Korea and Japan
Some 30,000 of these breath-holding divers,
called ama, are employed in daily foraging
for food on the bottom of the sea.
Their performance is of particular interest
to the physiologist
"She carries a counterweight (of about 30 pounds)
to pull her to the bottom..."
"If she dives deeper than the level of maximum
lung compression (her "residual lung volume"),
she becomes subject to a painful lung squeeze;
moreover, because the hydrostatic pressure in
her blood vessels then exceeds the air
pressure in her lungs, the pulmonary
blood vessels may burst. "
"Lanphier has calculated that repeated dives to
depths of 120 feet, such as are performed by male
pearl divers in the Tuamotu Archipelago of the
South Pacific, can result in enough accumulation
of nitrogen in the blood to cause the bends
on ascent."
"To compensate for this loss the Korean diving
woman eats considerably more than her nondiving
sisters. The ama's daily food consumption amounts
to about 3,000 kilocalories, whereas the
average for nondiving Korean women of
comparable age is on the order of 2,000
kilocalories per day."
"They showed, for one thing, that with the same
thickness of subcutaneous fat, divers had less
heat loss than nondivers. This was taken to
indicate that the divers' fatty insulation is
supplemented by some kind of vascular adaptation
that restricts the loss of heat from the blood
vessels to the skin, pmticularly in the arms and
legs. Secondly, the observations disclosed that
in winter the diving women lose about half of
their subcutaneous fat (although nondivers do
not)."
Quite a number of interesting facts.
http://userhome.brooklyn.cuny.edu/anthro/jbeatty/CORESEA/AMA.pdf
The Diving Women of Korea and Japan
Some 30,000 of these breath-holding divers,
called ama, are employed in daily foraging
for food on the bottom of the sea.
Their performance is of particular interest
to the physiologist
"She carries a counterweight (of about 30 pounds)
to pull her to the bottom..."
"If she dives deeper than the level of maximum
lung compression (her "residual lung volume"),
she becomes subject to a painful lung squeeze;
moreover, because the hydrostatic pressure in
her blood vessels then exceeds the air
pressure in her lungs, the pulmonary
blood vessels may burst. "
"Lanphier has calculated that repeated dives to
depths of 120 feet, such as are performed by male
pearl divers in the Tuamotu Archipelago of the
South Pacific, can result in enough accumulation
of nitrogen in the blood to cause the bends
on ascent."
"To compensate for this loss the Korean diving
woman eats considerably more than her nondiving
sisters. The ama's daily food consumption amounts
to about 3,000 kilocalories, whereas the
average for nondiving Korean women of
comparable age is on the order of 2,000
kilocalories per day."
"They showed, for one thing, that with the same
thickness of subcutaneous fat, divers had less
heat loss than nondivers. This was taken to
indicate that the divers' fatty insulation is
supplemented by some kind of vascular adaptation
that restricts the loss of heat from the blood
vessels to the skin, pmticularly in the arms and
legs. Secondly, the observations disclosed that
in winter the diving women lose about half of
their subcutaneous fat (although nondivers do
not)."