My waist was 27 inch and it had gone down to 24 inch just using this hula-hoop ... I did not do other exercise much. Make sure you have to spin it fast when you play the hula-hoop so that 1-hour exercise is really 1 hour. If you do it slowly, 1 hour could be equivalent to 30 min or even less. The best way to do it is to switch on some sort of pop music with fast rhythm, spin the hula-hoop along and you will follow the rhythm and get by the 1 hour very easily.