Some people refer to this style of walking as "power walking." With a small one or two pound weight in each hand and swinging the arms, you can get a boost to your workout. You'll keep your pace up and raise your heart rate. You may even burn a few more calories and shed an extra pound or two.
There's the added advantage of stress on the bones of the upper extremities, which can help with osteoporosis. Bone growth is stimulated whenever tension is applied by the tendon to the bone.
Some men and women who try this method of walking say it helps them remember to swing their arms and keep a more moderately brisk pace.