Agility dogs lacking core strength from routine physical exercise are more susceptible to one of the most common canine knee injuries, a cranial cruciate ligament rupture, which is similar to an anterior cruciate ligament (ACL) tear in humans. According to a research survey documenting activity and injury odds of more than 1,200 agility dogs, just about any physical exercise seems to lower the risk of rupturing the ligament, however some exercises can increase the risk. In addition, the size and shape of the dog, and thereby certain breeds, were also found to be at higher risk.

Balance and core strengthening exercises, in addition to well-known activities such as dock diving, barn hunt and scent work, are associated with a decreased rate of ligament rupture.

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