What is a one-sentence summary of the following article?
The most effective way to warm your hands is to exercise, which gets the blood pumping to your muscles and skin, warming your entire body.  Pick up the pace a little if your hands get cold when you are out walking. Do some chores to get yourself moving. Do some squats, jumping jacks, or other aerobic exercises. Getting up and exercising on the spot isn’t always an option, so if your hands get cold and you can’t increase your heart rate with aerobics, do some hand and foot exercises.  Wiggle your toes and fingers Move your hands in circles Clench and release your hands and feet Another way to get the blood flowing to your hands again is with a massage. Especially in the winter months when skin gets dry, spend some time massaging oil or cream into the skin of your arms, wrists, and hands. Don’t forget to massage in between your fingers and your fingertips. Although this is a more long-term approach to warming your hands, both smoking and caffeine cause your blood vessels to constrict or narrow, and if there isn’t enough blood flow to your hands, they will get cold. In cold months, try white teas instead of coffee to get your mornings going.

Summary:
Get moving. Do hand exercises. Massage your hands and arms. Stay away from cigarettes and caffeine.