Cold weather training
Cold weather forces your body to work harder during training, and this also applies to your cardiovascular system. As the heart works harder to pump blood around the body during cold weather exercise, this invigorating workout helps to keep your heart health in tip-top shape.
During running, thermoregulatory metabolism, which keeps core temperature steady at rest, is adjusted through a body temperature independent mechanism to compensate for the exertional heat generation. The colder the environment, the higher the metabolism at rest, and the more complete the compensation is.