The added weight can elevate your exercise to a new level, however it can also increase stress to your hip, knee and ankle joints that could led to injury. The idea of adding weight to burn more calories per mile is not worthy of the risk involved while walking. So, adding weight while walking would not do more good to your health but would just increased your risk to injury.
Moreover, the wrist weights, hand weights, flexing devices and various pulley system would give you an upper body workout while you walk but this is an unnatural and inefficient arm motion while walking. Instead, use proper arm swing to gain upper body toning and good walking posture.
