A man exercising Sweating is an important function which helps the body perform
exercise for longer
The adage "men perspire, women glow" is correct, according to Japanese
researchers, who found men are much more efficient at sweating.
Women unused to physical exercise had the worst sweating response, says the
research in Experimental Physiology which confirms previous findings.
This could mean women suffer more in hot temperatures as sweating helps the
body deal with heat.
A UK expert said women had less body fluid so could not lose as much as men.
The researchers asked 37 people to cycle continuously for an hour in a
controlled climate with increasing intensity intervals.
They were divided into four groups - trained and untrained females, trained and
untrained men - and the rate at which they produced sweat was measured.
Start Quote
Women are at a disadvantage when they need to sweat a lot during exercise,
especially in hot conditions
End Quote Yoshimitsu Inoue Osaka International University
The results of the study showed that while physical training increases sweating
in both men and women, the degree of increase is greater in men.
And the difference in sweating between the sexes became more pronounced as the
intensity of the exercise increased.
The sweating rate depends on the sweat output per gland.
Testosterone link
But women needed to get hotter, or work harder, than men before they got
sweaty, says the study.
This was particularly noticeable in the untrained women.
Sweating is known to help the body perform for longer when exercising.
Previous studies have shown that men have a higher sweat output than women, in
part because testosterone is believed to enhance the sweating response.
Lead researcher Yoshimitsu Inoue, from the Laboratory for Human Performance
Research at Osaka International University, said: "It appears that women are at
a disadvantage when they need to sweat a lot during exercise, especially in hot
conditions."
Mr Inoue explained why he believes the sexes have evolved to sweat differently.
"Women generally have less body fluid than men and may become dehydrated more
easily.
"Therefore the lower sweat loss in women may be an adaptation strategy that
attaches importance to survival in a hot environment, while the higher sweat
rate in men may be a strategy for greater efficiency of action or labour," he
said.
The findings could help to shed light on why men and women cope differently
with extremes of temperature like heatwaves.
But researchers says that exercising regularly before a heatwave comes will
help both men and women acclimatise better.
Professor Tim Cable, director of the school of sports and exercise studies at
Liverpool John Moores University, said sweating is a good thing not a bad
thing.
"The cooling effect on the body happens more quickly when we sweat. Females can
less afford to lose fluid than males because they have a smaller store of body
fluids to start with."
"It's likely that women lose heat by other mechanisms. They may lose more heat
via the skin because of their size and surface area - in the same way that
smaller animals lose more heat than big animals," he said.