Characterizing the Exercise Workloads and Energy Needs of Horses

be a higher intensity. Intensity can also be estimated by the horses average heart rate. 
It has been found that there is a relationship between the horses heart rate and its oxygen uptake. The horses oxygen uptake refers to the amount of oxygen inhaled by the horse that will then be used to fuel metabolism within their skeletal muscles during exercise. Estimating the oxygen uptake helps researchers estimate how much energy is being expended by the horse during exercise. However the average person cannot measure how much oxygen is being used by their horse. Observing the horses heart rate is a more userfriendly way to estimate how much oxygen is being utilized and thus how much energy is being expended during exercise. As the heart rate increases more oxygen will be used by the horse to fuel their movement during exercise. The heart rate can be accurately measured using an equine heart rate monitor Figure 1 2.
Figure 1. Horse wearing an equine heart rate monitor prior to being tacked up. Photo credit Erin Orr Penn State.
Measuring the horses pulse by hand is not an accurate way to determine the horses heart rate during exercise. By the time a horse comes to a stop and the rider dismounts to check the pulse the horses heart rate has already drastically decreased. Using an equine heart rate monitor can track the horses heart rate over the entire exercise session and provide an opportunity to calculate the average heart rate. The NRC table provides some general heart rate averages that may be found for each exercise level. The use of an equine heart rate monitor in addition to identifying the frequency and duration of exercise may help to properly estimate a horses workload.
Once you have determined the duration frequency and intensity within a horses exercise

routine you can use the table created by the NRC to determine if your horse fits into the light moderate heavy or very heavy exercise category. This table can direct you in determining your horses energy needs and how you may need to make nutritional adjustments to meet these requirements. 
Exercise Requires Energy
For each exercise level the 2007 NRC also provides daily energy requirements. To provide some reference an adult 1000pound horse at an average maintenance level meaning the horse is not in work pregnant lactating or breeding requires about 17 megacalories Mcalday. Horses within the different exercise categories would then need a