Are horses with thin legs faster than horse wider legs?

The thickness or thinness of a horse's legs does not directly correlate with its speed. Several factors, including breed, conformation, muscle mass, and training, influence a horse's speed. Some horse breeds, such as Thoroughbreds and Arabians, are known for their speed and often have relatively long, slender legs. However, there are many other horse breeds with thicker legs that can also be very fast. Ultimately, a horse's speed depends on a combination of factors, and leg thickness alone is not a reliable indicator.