My Pulsense device does not appear to detect my pulse when I wear it in cold weather. Why does this happen?

• Cold weather can cause the blood flow at your wrist to decrease and the Pulsense device may not detect your pulse. The Pulsense device is meant to be worn in temperatures that range from 23°F to 95°F (-5°C to 35°C). If you wear it in an environment where the temperature is below 23°F (-5°C), wear warm clothes to keep your body warm and protect the device.