While cones, hurdles, and the like can serve a purpose, the majority of the exercises programmed with them are huge time-wasters. As an athlete, having finely tuned agility is necessary to compete at the highest level — regardless of your sport or position. Unfortunately, most agility training uses gimmicky equipment to fool athletes into thinking they are doing something productive.
During competition, athletes have to react to a live stimulus. They must change their body’s position efficiently based on what is happening around them, in real-time. At no point during an athletic competition does your opponent tell you what they're going to do next and give you time to prepare for it.
Reactive agility drills throw an unpredictable stimulus at the athlete. This stimulus can be any visual or auditory cue, such as the pointing of a hand or blow of a whistle, which the athlete will need to respond to. Reactive agility exercises add a level of unpredictability, unseen in the standard, predetermined drills. This randomness replicates a true stimulus-response experience, better preparing athletes for actual competition.
Read about the drills over at Train Heroic.