Surfers two or four people enter the water and ride the waves repeatedly in a 20-minute period. Although the rules vary in each organization, a five or six-person jury evaluates the best 2, 3, or 5 moves. The criteria are: wave selection (more difficult, more points), position on the wave (the higher the better), the time spent on the wave, and the quality of the movement. In the four-man competition, the best two advance to the next round. All level competitions have separate races for men and women.
Movements on large waves are quite dangerous; so surfers have to be good swimmers. Professional surfers have a great sense of fitness and balance. The ability to choose the best waves comes from some local knowledge and some experience. Training on land is meant to strengthen leg muscles.
Surfboards are traditionally made of wood, but now fiberglass is also used; most boards now weigh less than 1 kilo. There are two different boards: short board and long board. Professional surfers use shortboards in competitions, but the ISA (International Surfing Association) still has a shortboard classification at the World Championships.
The longboard is much more stable but harder to turn, so it’s often used by beginners. The shortboard is lighter and rotates more easily. This type of lacquer or non-slip plastic area allows the athlete to hold on more comfortably. The surfboard is attached to the athlete by the ankle so that the two are inseparable. Small wings at the back and rear of the board increase stability.