In 1976, at the age of 18, American Brad Parks found himself in a wheelchair. Five months after the accident that paralysed Parks, he tried hitting a ball on holiday with his parents. He experienced the need to bounce the ball twice and was immediately enthusiastic about the sport. A month later, Parks began actively playing wheelchair tennis with his therapist Jeff Minnenbraker. In 1977, they started promoting the sport and soon after, the first wheelchair tennis tournament in history was held in Los Angeles. Since then, the sport has grown tremendously. In 1988, it was a demonstration sport at the Paralympic Games, and since 1992 it has been a regular part of the Summer Games. Today, the sport of wheelchair tennis is practised worldwide. The international tournament calendar had 140 tournaments in 2009. The year-end championships consist of the Wheelchair Tennis Masters (singles) and the Wheelchair Doubles Masters (doubles). In addition, there is the World Team Cup, comparable to the Davis Cup and Fed Cup in able-bodied tennis.