ridecamp@endurance.net: [endurance] Sweat vs. Lather

[endurance] Sweat vs. Lather

ChacoL@aol.com
Fri, 8 Mar 1996 02:23:14 -0500

According to the book, "Equine Fitness," published in England but an
excellent reference:

The proteins found in the sweat glands are of a special type and their nature
suggests that they have detergent-like properties. This means that they aid
in the dispersion of the sweat droplets into a thin film along the hairs, and
this helps evaporation. We are able, therefore, to explain some observations
known to all horsemen, i.e., that sweat readily lathers, and also that as the
horse becomes fitter the sweat becomes more watery. In horses exercised
frequently (and so presumably becoming fitter), the protein content of the
sweat decreases because the time required for its replacement cannot keep
pace with the rate of its secretion in the sweat.

Also of note in the same chapter on Thermoregulation:

Large amounts of sodium, potassium, and chloride (as well as calcium and
magnesium) are lost from the horse during sweating. This means that, at a
similar rate of sweating to a man, a horse will lose about three times as
much sodium chloride and five to 10 times as much potassium as the man.

And further:

As a general rule, a horse which is sweating moderately heavily will be
losing about 8 3/4 pints of sweat per hour (5 liters). Each liter of this
sweat contains 7.5-10.5 grams sodium chloride and 1.5-3.5 grams potassium
chloride. In a 50 mile ride held in a cool climate, Thoroughbreds were found
to lose 8 gallons (3 litres) of sweat over a five-hour period. This
corresponds to a loss of about 3/4 lb of salt, which is equivalent to between
one-third and one-half of their total body sodium chloride content. Horses
exercising at a fast pace in hot, dry climates will have sweat losses two or
three times this amount.

Something to think about in planning your electrolyte replacement program.

Linda Romander
San Francisco, Calif.