BOSU™ is an acronym for “both sides up”. The BOSU® Balance Trainer can be used with the platform side either up or down for different types of balance challenge. The solid platform is 25 inches in diameter and the dome should be inflated until it is firm. Two recessed handles on the bottom of and towards the sides on the platform make it easy to turn over or carry. This hybrid fitness product has its genesis in the field of medicine, as well as balance, functional and sports specific training. Neuromuscular physiology, which helps to define human movement, provides the science that backs this remarkably complete approach to training. The BOSU® Balance Trainer offers a different means to make exercise more appealing and effective for average people, fitness enthusiasts and highly trained athletes.