Is your horse fit? Cardiac recovery index

Have you ever wondered if your horse is fit enough to handle his exercise regimen? Do you worry after an intense ride if you overdid it? Are you sometimes unsure how environmental conditions (heat, humidity) are affecting your horse? The cardiac recovery index is used at vet checkpoints in distance rides to assess if a horse is overly stressed or fatigued. It's a simple test and might help riders evaluate their horse's fitness and work program.

What is needed
You can do the test during or after a workout. The test requires a stethoscope; a flat, comfortable trotting surface 125 feet long; and a stopwatch or watch with a second hand.

The procedure
How to do the test:

1. Take the horse's heart rate. Place the stethoscope just above the elbow on the chest wall. Start a stopwatch and count the heartbeats up to fifteen seconds. Multiply the number by four to calculate the number of heartbeats per minute. The average resting heartbeat will be 30-40 per minute, but if your horse has been exercising it will be higher, of course.
   
2. Reset the stopwatch. Start the stopwatch again as you trot the horse up and down the 125 foot (38 meter) path (total distance 250 feet or 76 meters).
   
3. You'll finish in under a minute. Wait with the horse until one minute has elapsed since you started trotting.
   
4. Immediately take the heart rate again.
   
5. Compare the heartrate before and after the trotwork.
   • If the "after" heart rate is equal to or lower than the "before" heart rate, your horse is fit to continue.
   • If the heart rate is 4 beats/minute higher, the horse is not fully recovered. Repeat the test in 10 minutes.
     
   • If the heart rate is 8 beats/minute higher, the horse is not fit enough for the workout. Repeat the test in 30 minutes if the horse's heart rate is still elevated, call it a day and monitor your horse carefully.

Causes of a false reading
Possible causes of a higher reading could be excitement/fear, injury, or heat stress/dehydration. A few tips to try if your horse's results seem artificially high. Try to remove distractions such as other horses, noise, and fearful situations. Do not let the horse eat while taking the pulse. Encourage the horse lower his head in a relaxed position (not thrown up). Pat or stroke the horse, and take a deep breath yourself. Sometimes the horse anticipates he'll need to trot again. Use body language to relax your horse and let him know there is no more work.

RESOURCES
Understanding the cardiac recovery index from HorseJunction

Resting and recovery heart rate fom distanceriding.org

CRI Cardiac recovery index from South Eastern Distance Riders Association

CRI: Appropriate and Inappropiate Use from Endurance Riders of Alberta