I travel for a living . I miss my weight at home and not all hotel offer a good exercise room . I purchase the Shake Weight because of it be size , weight and portability , but really do not think it would be all that effective . now the Shake Weight have become my favorite exercise . after use it on the road a few day I notice I could increase my rep or weight on my set at home . muscle definition become apparent after a few week . so I use the shake weight every time I exercise . it be my warm up before my weight training and my primary exercise on the road . my only wish be if they make something that effective for the lower body as well . if you be very much out of shape and overweight , I would suggest weight loss before any exercise program . I lose over 70 pound before get serious about the exercise . how ? see -lrb- ... -rrb-