The use of boots or leg wraps very much depends on what you want to get
out of the boots or wraps. You should carefully examine what you want to
do and how much boot to use.
Horse leg wear comes in two types: impact protection (in case he
bangs himself, or bangs his leg on something else) and
support.
If you always use support for your horse's legs, then the legs are never
"exercised" enough for them to develop their own strength (stretching and
absorbing concussion; tendons, ligaments, bones). So if you want to do
more, but your horse is already using maximum support all of the time, how
do you up that support for greater stress and impact?
If your exercise regimen is begun slowly and increases steadily but not
too fast, then he will develop strength of his own. If he is fully
supported, he will never need to develop structural strength, and if you
should ask for more effort, he may do damage because the legs do not have
the right internal support structure. It makes more sense to me to depend
on the horse to develop internal strength in his legs, and then support
him when you are asking for more than his usual effort.
If you're going to be in a long session, say 3x as long or 3x as hard as
usual, you'd want to provide extra support. For example, if the horse is
used to galloping a mile and a half, and also used to jumping 15 jump
courses, then you could probably provide simple impact protection for
either; but I'd want to put SMB's on to do a mile & a half
cross-country course with 15 jumps in it. I usually handle it by using
splint boots for impact protection for most normal work; they don't
provide support. I'll use support boots when showing, when riding
cross-country jumps, or when asking for unusual exercise. Typical work,
typical exercise, the horse should be able to handle with his own
legs.
"Sports Medicine"-type boots provide support for the tendons and
ligaments in the fetlock, as well as impact protection.
SMB-type boots go all the way around the fetlock, and apply pressure
all around. They're like an ankle or knee brace. They work well for
situations in which the horse will be asked to perform more than usual
(shows, riding cross country, slippery terrain). Consider carefully
before using them all of the time; if you use them all the time you
prevent the horse's leg from developing its own strength.
Open front jumping boots also provide some support to the fetlock. They
do not go all the way around, and the straps do not directly affect the
joint. They provide less support than SMB-type boots, but they do
provide some. They allow more freedom of the joint than SMB-type
boots.
They do not protect the front of the horse's leg. Open front boots may
not be suitable for riding in areas where the horse is likely to get
banged a lot (riding through brush, for example).
Splint boots (and brushing boots) provide only impact protection. They
have no support for the joint. They work well for situations where a
horse may be expected to interfere (lateral or circle work). They also
work well in situations where the horse may be expected to bang his
legs occasionally, but won't need leg support (trail rides, for
example).
Polo wraps alone do not provide leg support. They are not as heavy as
neoprene boots, and cannot be pulled tight the same way. It's just not
feasible to wrap a horse's leg in a polo wrap such that it provides
support.
You can use track bandages over padding, but that's not the same as a
polo wrap by itself.
Polo wraps are very pretty as decoration and provide impact protection.
Stable wraps (or stable bandages) consist of a stable bandage wrapped
tightly around thick quilts or other padding. Stable wraps provide
support for a horse's leg in situations where he may be putting an
undue amount of stress on a leg, or impact protection in situations
where he may be in danger of injury. They should only be used in a
stall or trailer; these wraps are not suitable for riding or
turnout.
Used in combination with bell boots, they make good trailering
protection.
When a horse has a leg injury (such as a bowed tendon), often his
injured leg may be wrapped for support and to prevent swelling. He may
also have his other leg (or all 3 other legs) wrapped in a stable
bandage, because he's putting less weight on the injured leg. His other
legs are supporting more weight.
After an unusual exertion, an exhausted horse may be wrapped in stable
bandages to support him and prevent any post-injury swelling.