A kettlebell is a weight that looks like a cannonball with a handle. Originating from Russia, kettlebell training is now a global phenomenon with clubs, gyms and individuals investing in equipment and training. Weights range from 4kg to 48kg. They differ from dumbbells and barbells in that the centre of mass is offset from the handle, so the weight constantly pulls against your hand, improving coordination and anaerobic fitness and strengthening your core muscles. Kettlebells can be used for a variety of purposes - from weight loss to strength training - by people with a range of fitness levels. Popular with celebrities such as Penelope Cruz and Sylvester Stallone, they are also used for training players at Chelsea and Liverpool football clubs, and in 2010 the British Army got on board when their PTI corp (responsible for the Army's physical training) signed up to a 30-day course designed and implemented by the author. The book includes information on the benefits of kettlebell training and how to use the equipment safely, and provides warm-ups, drills and training programmes for beginner, intermediate and advanced levels. From buying a kettlebell to training for weight loss, it's a comprehensive guide to a popular new fitness tool.