by Jenn Ess
Learn more about Jenn at the end of this article.

WATER: In the horse and On the horse

In the horse: Always allow and encourage horses to drink as much as they want!

It is a myth that drinking too much water or drinking cold water during/after exercise will harm horses. They are working and need as much water as they can get to stay cool and hydrated.

Dehydration is a serious health concern!65% of a horse’s body weight is water. Most water lost during exercise is lost through sweating. Most water lost through sweating is pulled directly out of the bloodstream.

Minor dehydration can cause poor blood flow to muscles and organs, low oxygen intake, loss of energy, and difficulty regulating body temperature.Severe dehydration can cause organ failure and lead to other health concerns like heatstroke/heat exhaustion and tying up/Rhabdomyolysis (See Heatstroke, Tying up below).

Supplement the amount of water your horse is taking in by wetting down their food before, during, and after riding. Most grains and pellets will absorb a certain amount of water on their own OR you can add soaked beet pulp to meals OR feed soaked beet pulp by itself.

On the horse: Carry a sponge while riding! Sponge water all over your horse during hot conditions to help them maintain a safe body temperature.

Factor in humidity as well as heat: Humidity prevents sweat from evaporating, so instead of pulling heat away from the body it sits on the skin and holds heat in. Scraping water off the horse after you sponge with a sweat scraper or hand will help to remove heat from the horse.

Check Your Horse:

  • Capillary Refill: Press your thumb against the horse’s upper gums. The color (pink flush) should return within 2 seconds of removing your thumb. If not — your horse is dehydrated.
  • Skin Tent: Pinch (gently!) a fold of skin on your horse’s neck or chest. The skin should snap back to its original place immediately after letting go. If not — your horse is dehydrated.
  • Rectal Thermometer: Normal temperature range for horses is 99 to 101.5 degrees. If body temp is higher than that — your horse is overheated.
  • Respiration: 8-16 breaths per minute is considered normal.
  • Heart Rate: 30-46 beats per minute is considered a normal resting heart rate. A horse in work will have a much higher heart rate but should be able to come back down to 64 BPM or less within a few minutes. You can check a horse’s heart rate by hand, with a stethoscope, or with electronic heart rate monitors.
    • Maxillary Artery: Press three fingers inwards and upwards underneath the cheekbone.
    • Radial Artery: Press two fingers just below the knee joint.
    • Digital Artery: Press two fingers on the underside of the fetlock toward the inside.

If it takes your horse more than 10 minutes to come back to a normal respiration or heart rate range it is a sign that they are becoming fatigued. Let the horse walk until they come back to a normal range and consider lessening their workload until fitness improves.

Overheating/Heat Exhaustion
When the horse’s internal body temperature rises above the normal and safe range.

  • Can cause lethargy, abnormal behavior, excessive sweating, foaming sweat, an absence of sweat in hot conditions, weakness, disorientation, heavy or irregular breathing, panting, and respiratory inversion (when respiration is quicker than heart rate. This is a sign that the body is struggling to take in oxygen and expel heat).
  • Can cause cell damage, brain damage, and organ failure.

Tying-Up (Rhabdomyolysis)
Uncontrollable cramping of the large loin and croup muscles.

  • Dehydration and electrolyte imbalances can both contribute to tying up.
  • Will cause dark-brown urine (this is blood and dead cells in the urine as the body breaks down muscle and organ tissue to get fluids and electrolytes). Is extremely painful and can be FATAL if left untreated. Call a vet immediately if you suspect a horse is tying up!

Emergency Cooling of the Horse
If your horse is showing signs of distress and needs to be cooled down quickly there are a few things you can do to help:

  • Continuously sponge cold water onto the horse and scrape it off again with either a sweat scraper or your hand (the water draws heat away from the skin but unless you remove it from the body it will become a blanket holding all that heat in).
  • Use ice water if you can get it. In an emergency cooling situation the benefit of bringing the horse’s temperature down overrides the possibility of a temporary muscle cramp from the ice.
  • Add rubbing alcohol to the sponge water. This mixture will evaporate quicker than water and help remove heat from the horse quickly. Do not allow any horse to drink water with rubbing alcohol in it and do not use this mixture over open cuts on the horse. It will sting!
  • Target large veins, arteries, and muscles for sponging: The neck, hindquarters, and between back legs have a large blood supply close to the surface of the body.
  • There is also a large vein that runs along the underside of the tail. If safe to do so, place a cold sponge under the horse’s tail. Most horses will clamp their tail down on the sponge.

FOOD: Before, During, and After Work

Today’s ride burns yesterday’s feed. Today’s feed replaces what the horse is losing through exercise, temperature regulation, and stress right now.

It is a myth that the horse’s stomach should be empty while exercising to avoid digestive upset. By forcing the horse to work on an empty stomach you actually cause gastrointestinal distress


  • Horses are grazing animals which are meant to be eating for the majority of their lives.
  • Because of this, horse’s stomachs produce acid at all times.
  • If there is nothing in the stomach for this acid to digest it will start to digest the lining of the stomach itself and can cause health concerns like sour stomach, diarrhea (which can easily lead to dehydration), stomach ulcers, and colic.

Feed your horse before the ride:

  • Feed for the amount of work you will be doing.
  • If you plan to ride at low or medium intensity of work for an hour or less you probably won’t need to add anything to your horse’s regular morning routine, but if you plan to ride at a high intensity of work, plan to ride for several hours at a time, or plan to ride at a higher intensity of work than the horse is used to doing, you will need to increase their feed accordingly.
  • Take this opportunity to get your horse loaded up on the things he will need during the ride: calories, water, electrolytes (see “Electrolytes” below).

Feed your horse during the ride:

  • If you are riding for more than two hours you need to give your horse something to eat so that they don’t burn through all the energy stores in their body or damage their own stomachs.
  • Let your horse graze for 10-15 minutes, carry a bag of treats to feed them, or carry a meal of your own feed to give them during a break.
  • Teaching a cue word or phrase can help prevent your horse from becoming pushy or rude about accepting food during work. Something simple like, “gentle,” “cookie,” or “snack,” will let them know when eating is appropriate.

Feed your horse after the ride:

  • Recovering from work is more than just rest.
  • The horse needs to replace everything they used during exercise and build the stores of the body back to normal, so feed them!
  • How much to feed will depend on how hard the horse worked, how long they worked, and what their normal dietary needs are.
  • Be sure to offer as much water as the horse wants to ensure good hydration. You can also wet their feed or give one last dose of electrolytes to be sure.

ELECTROLYTES – So much more than salt!

  • Sodium: contributes to cellular fluid balance, muscle contraction, and conduction of nerve impulses
  • Calcium: contributes to the release of hormones, muscle contraction, and transmission of signals between nerves
  • Potassium: contributes to heart function, muscle contraction, and digestive function
  • Magnesium: maintains nerve and muscle function, supports the immune system, contributes to regulation of the heartbeat, and strengthening of skeletal bones
  • Chloride: maintains proper blood volume, blood pressure, pH of bodily fluids, and maintains proper fluid balance between the inside and outside of cells

Notice the importance of the functions electrolytes contribute to – these are vital functions!

Feeding sodium alone will not benefit your horse!

  • Horses expel excess salt through urination
  • A large excess of salt in a horse’s daily diet will actually encourage dehydration by causing fluid retention (remember sodium contributes to fluid balance on a cellular level) and may cause them to drink less than they normally would.

Feed the electrolyte that suits you!

  • Powder electrolytes: Can be given mixed in feed or mixed with a buffer like molasses, yogurt, or baby food to be given orally in a large syringe. You must provide a buffer for powder electrolytes or you will burn the horse’s mouth, throat, and stomach linings.
  • Paste electrolytes: Can be bought pre-mixed and pre-buffered in large syringes for oral dosing and can be carried with you during a ride. It’s a good idea to carry at least one dose of electrolytes during a long ride in case your horse or a friend’s horse needs it.

Water additives only work if the horse is accustomed to them!

  • There are special types of electrolytes that are meant to be added to a horse’s drinking water.
  • If the horse is used to having these additives in their water and drinks them happily, good!
  • If the horse is not used to additives, be aware that adding something like this to drinking water unexpectedly or only during a ride may actually deter the horse from drinking and cause problems rather than alleviate them.

Why should I give electrolytes now when my horse has always done fine without them?

  • Why would you not use something that is proven to improve performance and reduce recovery time in your horse?
  • Electrolytes are instrumental in prevention and treatment of serious, sometimes life-threatening, health concerns. (Have you ever asked your vet exactly what’s in that IV drip bag?)

Electrolyte Imbalances
Lack of electrolytes can contribute to several serious health concerns.

  • Thumps: Similar to hiccups in people. When respiration mimics the heartbeat. This can be
    linked to low blood calcium levels and dehydration.
  • Tying Up (Rhabdomyolysis): (See “Tying Up” above ^^.)
  • Any Abnormal Behavior: Remember that electrolytes play a large role in transmitting signals between nerves, release of hormones, and coordination of muscle contractions. If your horse is suddenly acting or moving different than normal s/he may be suffering from an electrolyte imbalance.

Always be aware! Is your horse…

Eating? Drinking? Peeing? Pooping?

Behaving normally?

Sweating an appropriate amount for the work intensity and conditions?

Showing normal and healthy vital signs?

No one has ever paid a vet bill for being too cautious, too attentive, or too educated in regards to horse care and management.

If you suspect any of the conditions mentioned above OR your horse is behaving abnormally during or after a ride CALL A VET.


About Jenn Ess.

I grew up competing in endurance with my mother from 2003 to 2011 before moving on to other disciplines with my horses, though I did dip my toes back in for the 2017 season.

I’ve always found it very disconcerting that the horse care and management I learned and depended on so heavily in one discipline is often entirely absent from others. I just assumed that everyone knew these things and it still comes as a shock when I learn that someone who’s been an avid and successful rider for years doesn’t know how to take their horses pulse or has no idea what electrolytes are. There seems to be a misconception that just because the horse doesn’t compete at a high level or works mainly in an arena that they can’t get into trouble metabolically, but that’s just not true, especially in parts of the world where it’s regularly hot and humid.

I don’t consider any of this specifically “endurance” or “trail” riding information. It’s HORSE information and it’s immeasurably valuable to anyone who rides one, in or out of an arena. We all want happy, healthy horses at the end of the day.


3 3 Comments

  1. It is FABULOUS and comprehensive! Very nice article!!!

  2. Carole Schuh

    Thanks Jenn!!

  3. Jen you couldn’t have said it better!

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