Which of the following is a key phase in the long jump?

The long jump consists of four recognised phases: the approach run, the takeoff, the flight (or air phase), and the landing. The approach run is a key phase in which the athlete sprints down the runway to build up maximum controllable speed before reaching the takeoff board. The speed generated during the approach run directly determines the horizontal distance the athlete can achieve, making it one of the most critical phases of the event.

The other options describe actions that are not standard long jump phases:

• The double arm swing is a technique element used in the standing long jump (and to some extent during takeoff), but it is not a recognised phase of the running long jump.
• The glide is a technique used in shot put, not long jump. There is no glide phase in the long jump.
• The crossover step is a movement used in throwing events (such as the javelin run-up) and in various sports for lateral movement. It is not a long jump phase.

During the approach run, consistency is vital. Athletes use check marks on the runway to ensure they hit the takeoff board accurately at full speed without fouling.