In which phase of the canter and gallop stride does a horse primarily exhale?

In the context of a horse's stride during canter and gallop, the phase during which the horse primarily exhales is the second phase. This phase corresponds to the moment when the horse's body is moving into a forward stretch after having pushed off the ground with its hind legs. During this time, the horse is transitioning in its balance and positioning, which involves the expansion of the thoracic cavity as the forelimbs reach forward. The act of pushing off and the forward motion create a natural inclination for the horse to exhale as part of its respiratory cycle.

Having a clear understanding of these phases helps in recognizing the horse's respiratory behavior during different gaits. The timing of inhalation and exhalation is crucial for maintaining rhythm and cardio efficiency, particularly under increased physical exertion typical of galloping. The second phase plays an essential role in helping the horse manage its energy and ensure optimal breathing patterns for performance.