In sports, sometimes you think you've maximized the potential of the human body after decades of competition, and then you get surprised (see: https://en.wikipedia.org/wiki/Men%27s_100_metres_world_recor... )
Perhaps the same is true for horses.
Perhaps the same is true for horses.
Edit: Can't find the study anymore. This one [1] at least partially attributes to material.
[1] https://www.balticsportscience.com/journal/vol17/iss2/2/