Tuesday, August 31, 2010

Hair, sun and heat

A strange study!

Head Hair Reduces Sweat Rate During Exercise Under the Sun


Anonymous said...

Makes sense. I always keep my hair trimmed with #4 clippers in the summer, less sweating and evaporation means hotter body and it has been over 90 degrees for 45 days in a row here, and humidity is high, heat exhaustion is a given when exercising outdoors and heat stroke is a real risk.

Anonymous said...

my guess- enough hair would reduce the radiant heat load reaching the scalp. Possible there is alayer of air cooled by evaporated sweat within the haired area? Head is known to be a major source of heat exchange in various heat strain situations.

Heat balance is determined by about several factors including radiant temp, air temp, air speed, humidity, clothing (& hair apparently), metabolic rate & workload (ie internal heat generated). Water input also. Sun is a source of radiant heat (infrared radiation) and indirectly heats the air ie radiant heat hitting surfaces in contact with air warm it up.
Just some quick thoughts.