Both are possible:

Standing starts emphasize muscular work and explosiveness.
Flying starts require less explosiveness and put less stress on your muscles and tendons, which helps reduce the risk of injury.

For short sprint intervals (10–15 seconds) designed to fully stimulate your explosiveness, speed production, and neuromuscular activation, standing starts are encouraged to get the most benefit. For longer sprints, it’s up to you.

Updated on: 16/06/2025