According to Physical Fitness Network, generally speaking, healthy women of medium height should start training from a kettle bell weighing 8 kg (male 12 kg). I am 157 cm tall and weigh about 47 kg. When I first started practicing kettlebells (I had hardly done exercise and weight training before), I started practicing from 8 kg and have been using it until now 12 kg. Don't let your weight scare you. The characteristics and fame of the kettle bell are that it can shape your body, give you beautiful body lines and never turn you into a woman. If you haven't exercised for a long time, or you really don't have the confidence to use an 8 kg kettle bell, you may start training with a 6 kg kettle bell, but it is really not recommended to use a 4 kg kettle bell unless you use two 4 kg kettle bells to train at the same time. Conversely, if you have the habit of exercise and fitness, and do weight training regularly, you can use a kettle bell with a weight of 12kg for training.