Page 99 - May 2022

USING A HEART RATE
MONITOR
by Nancy S. Loving, DVM
Ahealthy heart is paramount to equine athletic performance. This fantastic pump incessantly beats day after day, year after year, pushing blood around the body to maintain organ health and to fuel locomotion and
heat dissipation.
As a horse exercises, muscles demand more oxygen. The call is answered by an increased heart rate, which bathes the working muscles with more blood. At rest, only 15% of the blood volume circulates to the muscles, while during exercise, blood flow to the muscles increases to 85%. The faster a horse goes or the more difficult the exertion, the more quickly his heart beats to deliver precious oxygen and nutrients. This rapid circulation of blood also removes metabolic waste products and heat from the tissues.
A simple piece of technology – a cardiotachometer or heart rate monitor – assists in understanding how well a horse copes with exercise stress and how safe is safe and how far to push a horse.
THE WORKING HEART RATE (HR)
VETERINARY VIEWS
© TRACKNER
At rest, only 15% of the blood volume circulates to the muscles, while during exercise, blood flow to the muscles increases to 85%.
One of the great advantages of a heart
rate monitor is the immediate information available about a horse’s heart rate while working. There is no other way to gather
this data – by the time a rider dismounts
and starts to take a horse’s pulse, it will have dropped by half, or be at least 20-50 beats per minute (bpm) below the working heart rate.
A heart rate monitor tracks exactly what is occurring with exercise, and this helps with strategies of incremental changes in training. Without this data, it may be assumed that a horse is not experiencing much stress when
in fact certain conditions and speed drive the working heart rate up significantly.
The best information is gained by using the monitor consistently to compare a horse’s day-to-day performance. Most horses find a pace that maintains their heart rate within a comfort zone. With few exceptions, horses are truly the masters of conserving energy. Whether in training or in competition, an elevation in a horse’s working heart rate that varies from his normal for a similar work
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