It’s all in the waist. Your core strength lies in your back and stomach muscles. The Adjustable Message Hula Hoop will train your back and stomach to be stronger, while also burning fat and helping you achieve a slimmer waistline. It’s not just a Hula Hoop. It’s s a complete portable fitness product that can be carried anywhere as it is engineered to be the most practical, interactive and effective workout tool on the market today .