Tennis is a world class competitive sport attracting millions of players and fans worldwide. Professional tennis players travel and compete extensively year round, with tournaments on the professional men's and women's calendars numbering between 400 to 600, including tournaments and team events for junior, seniors, and wheelchair players. Thus, there are many different opportunities for all levels players to compete in any given week of the year. In addition, tennis is a common recreational sport, which is enjoyed by people of all playing abilities. Tennis has evolved from a technical/tactical game, based on style and finesse to the current fast paced, explosive sport based on physical abilities, where serves over 200 km/h are common. Therefore, to be competitive and successful, tennis athletes will need a complex interaction of physical components (i.e., speed, agility and power combined with medium to high aerobic capabilities). Underlying these physical components are cognitive and psychological processes, allowing the athlete to cope with ensuing fatigue and the pressures of match-deciding points, as well as significant extrinsic rewards (e.g., ranking, money endorsements). The evolution of tennis play over the last
20 years has led to an increased interest in tennis research and several groups have been working to create an interdisciplinary sport science approach to further understand the interaction between the different sport science disciplines (e.g., biomechanics, physiology) and performance in tennis. The aim of this tennis special issue is to provide a better understanding of the complex demands of tennis, from an interdisciplinary point of view, including papers related to biomechanics, physiology, nutrition or health. I hope that the readers could find all this interesting information useful.