Join Date: Sep 2009
Location: Tampa Bay area, FL
I also have a TB, and your horse should be perfectly fine to be ridden in winter, as long as he doesn't have any problems sweating. I know of some TB's who have problems working up a really good sweat and they have to be cooled down extra carefully. As with any horse, make sure he's conditioned properly before competing, especially on something long winded like competitive trails. Depending on his body type, he was either meant to cover short distances very fast (Sprinter) or longer distances very fast (Stayer).
Since TB's were bred to run, they have big hearts and great lung capacity and deep chests, but their legs and hooves are often not up to par for things like navigating rocky terrain with ease. If that's what you plan on doing, make sure he has shoes and other protective gear.
Does he come from racing stock, or was he backyard bred? Most TB's have some race horses in their history, but if you got him from a trainer who decided not to race him because he wasn't fast enough, his conformation is going to be affected, rather than someone who bred their mare to someone's stallion--these horses are more likely to be crossed with something along their bloodlines but not show traits. Over all though, TB's are pretty much good for whatever discipline you choose to train them in--they're very willing and naturally athletic.