As colder temperatures approach and daylight becomes shorter for those of us in the Midwest, our horses' coats grow longer. Horse owners that continue to work their horses throughout fall and winter must consider whether or not to body clip their horses. Many factors play into this decision, such as how often and how hard the horse is worked, if the horse is living out or mainly in a stall, how long the horse's coat grows, and how the horse tolerates clipping. The first body clip generally happens in October or November and you may have to clip again in January or February, but you have to watch if you clip later than February because a later clip could affect the horse's summer coat.
Horses with winter coats who are expected to perform are a lot like people who workout in colder temperatures. When it is a little cooler, people may wear extra layers while at rest. However, if I go out for a 30 minute run while it is 45 degrees outside and wear insulated socks, long underwear, sweatpants, a long sleeve shirt, a sweatshirt, a winter jacket, a scarf, gloves, and a hat and never take any layer off, my body temperature is going to rise significantly and my body will start to sweat as I run. However, all these layers are going to trap that sweat and may cause me to become chilled if I don't loose some layers. As a human being, I have the conscious awareness to change this situation. If I start to overheat on my run, I can remove layers of clothing, so I can continue to exercise and be at a comfortable temperature. Horses, on the other hand, do not have the capacity to remove that extra layer of insulation while they exercise. So, if you start to notice your horse sweating and taking longer to cool out as their winter coat comes in, you may want to consider some type of a body clip to make your horse more comfortable while they are working.
My horse's workload does not change in winter, and he does grow a winter coat. While his winter coat is not very thick, my horse becomes too hot and will sweat considerably from a normal workout if I do not clip him. He tolerates clippers well. So, in order to keep him working more comfortably in winter, I choose to body clip him. I do a full clip on him, which takes all the hair from his body and legs off. After I clip him, I blanket my horse. Remember, through body clipping you remove the horse's natural layer of insulation and protection from the elements. So, you must insulate the horse in cooler temperatures with a stable blanket or winter turnout (when they go outside) if the temperatures are cold. For warmer temperatures, an unlined could suffice. If you are unsure about what type of blanketing option is appropriate for your horse please consult a professional from a local tack shop or blanket company, if you do not have a trainer t consult, BEFORE YOU BODY CLIP, because immediately after you finish body clipping, you will want to put a blanket or turnout on your horse.
If you don't have the ambition or equipment to body clip your horse, you can always ask a trainer or a groom for referral, if they don't clip themselves. It is a good skill to learn, but is messy and can be time consuming, so its best to learn on a tolerant horse that you can mess up on like a school pony or horse before clipping a high level performance horse.
Read more about body clipping from Dover Saddlery here