What is sweat?
	sweat contains water and salts.
	horse sweat is about 10x more concentrated than human sweat!
	the main electrolytes in sweat are sodium (Na+), potassium (K+), chloride (Cl-), magnesium (Mg++) and calcium (Ca++).
	losses of electrolytes and water affect health and performance.

What are electrolytes?
	electrolytes are electrically charged particles in solution; some have a positive (+) charge and some have a negative (-) charge.
	sodium (Na+) is most abundant in the fluid outside the cells, whereas potassium (K+) is most abundant inside the cells (like the muscle).
	Na+ helps balance the body's water and maintains blood pressure.
	K+ helps balance the fluid inside the cells and is important for optimal muscle, heart and kidney function.
	Cl- helps maintain the balance of acids and bases.
	Mg++ is important for many functions in the body and contributes to the skeletal growth.
	Ca++ builds bones and teeth and contributes to healthy function of the heart, muscle, nerves and blood clotting.

How does sweat help heat loss?
	sweat must evaporate in order to take heat away from the horse efficiently.
	if the weather is hot and humid, the sweat will not evaporate quickly.

Sweating Buckets?
	the human sweat rate is only 2-3 L/h.
	the horse's sweat rate can be 10-15 L/h!
	talk about sweating buckets!

It’s not the heat, It’s the humidity?
	if a horse is exercising in the heat, endurance time may decrease by 25%.
	if it is hot and humid, endurance time may decrease 50%!
	always be aware of the humidity when exercising your horse.
	learn how to monitor the temperature of your horse.
	slowly acclimate your horse to exercise in the heat.

Are you a weather watcher?
	if conditions include warm to hot temperatures, help cool down the horse to "save sweat".
	repeated applications of water with a sponge will help to take heat away;
	continue sponging until the water coming off the skin is the same temperature as it went on.
	if weather conditions are hot and humid, use caution when exercising to avoid overheating the horse.
	if weather conditions are very hot and humid, consider stopping all exercise if more than one hour duration.

By Gayle Ecker and Leslie Huber D.V.M
Equine Research Centre
Guelph, Ontario, Canada

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