What is the name for drills where athletes work to improve speed and start times, such as shuffle starts?

The term "accelerations" specifically refers to drills designed to enhance an athlete's speed and improve their start times. This includes various practices like shuttle runs, explosive starts, and other techniques aimed at increasing quickness off the line and responsiveness. Accelerations are critical for athletes in many sports, as they need to reach peak speeds quickly at the beginning of their performance.

In contrast, agility drills focus on improving an athlete's ability to change direction quickly and maintain control, which may not specifically center on start times. Endurance training emphasizes building stamina over long durations, whereas interval training involves alternating between high-intensity efforts and lower-intensity recovery periods, which is more related to cardiovascular fitness than solely speed improvement. Therefore, the correct answer distinctly highlights the focus on improving speed through specific drills.