Why Proper Movement is so Important
Auxiliary Heart Pumps
The horse's circulatory system is dependent on the loading and unloading of the properly functioning hoof in order to perform at max capacity. With each footfall blood is drawn into and pumped out of the hoof capsule to to circulated through the rest of the system. In fact studies have shown that a stationary horse has 80% less circulation than a horse that is walking. That's pretty significant.
Use it or Lose it
The hoof in a healthy horse similar to muscle needs constant stimulation and exercise in order to build strong healthy tissue. This is only achieved through the loading and unloading of the hoof through, you guessed it, movement. And proper heel first landing movement. (There can be a few exceptions where it would be better to limit movement for a short period of time for example in the case of acute laminitis, torn tendons/ligaments, or fractured/broken bone(s))
So How Much is Enough?
Each horse of course has different movement requirements however some minimums that have been recommended are 60, 000 steps or 6 miles per day, which for the most part gives you an idea of how much movement we're talking about. Ways that you can increase your horses movement are as follows:
Provide them with 24/7 outdoor turnout when possible
Turn them out with a pasture mate
If they are being fed hay, spread the hay all over their pen in small amounts so they have to move from pile to pile in order to get their fill. If that isn't possible move the food source as far away from their water source as possible.
Provided the horse is currently sound, start an exercise regimen. Trail rides, arena work, lunging, in hand walks, etc. It doesn't have to be fancy just get going :)!