Shipping Included Benefits: A number of recent studies have shown that carrying 3- to 5-pound weights in each hand while running or walking increases the metabolic cost or intensity of the activity. They also add some upper body muscular conditioning that is normally lacking in these activities. As a result, Heavy Hands are useful to fitness walkers, joggers, and runners who want to increase their training levels without increasing speed or distance of their workouts. Read more at the University of Florida's Website. The Heavy Hands handles are 1lb in weight, come in regular and large sizes and the colors Red and Black. Add the screw-on weights (items 46902 and 46903) to increase the weight of each handle. These are the Large Black handles.