The fitness sector is a subsector of sport that has had a great growth in number of sports facilities, consumers and economic impact worldwide. In the same way, it is a sector that has adapted to the needs of consumers in terms of digitization. However, technological changes, their use and the pace of adaptation have been different depending on the geographical area. That is why this book will show how different countries in the world have adapted in the digitization of the fitness sector, showing good practices and processes to take into account for an improvement of the digital transformation of fitness. Each chapter will show an introduction to the sector and main technologies related to the country and fitness; Later, he will carry out a case study of the digital transformation of a fitness center or chain of fitness centers in the country. It will end with the conclusions and how the case study can offer tools or good practices for implementation in other countries or in fitness centers.