Speed and agility are important aspects of athletic performance and are necessary for success in any sport. Agility refers to the speed of changing direction of movement without impacting balance to maintain momentum, while speed means the ability to go from one point to another in minimum time. Speed and agility not only help you perform better athletically, they also help decrease your risk of injury.
Understanding Speed and Agility
Speed is the distance covered by an athlete in a given time. It consists of several components: maximum velocity, speed endurance, and reaction time(1). Agility on the other hand is a multidimensional skill including coordination, balance, quickness, as well as the ability to make educated decisions right away in a sophisticated environment(2). Athletes who play high speed sports such as soccer, basketball and tennis require both speed and agility(3).

The Role of Muscle Fibers and Neuromuscular Adaptations

Speed and agility are determined by the type of muscle fibers an individual has. There basically two types of muscle fibers. Slow twitch (Type I) muscle fibers produce less force and contract slower than fast twitch (Type II). While fast twitch fibers are involved in explosive movements(4). Plyometric exercise training works on both of these fibers and, therefore improve speed and agility(5). Studies of high intensity interval training and resistance training have also shown that athletes who train regularly improve sprinting speed and agility significantly(6).
Training Techniques for Speed and Agility
The best drills to train for speed and agility combine a variety of drills that train different parts of the skills. For example, a sprint training system attempts to improve acceleration and maximum velocity(7). Agility drills such as ladder exercises, cone drills, and shuttle runs improve how an athlete can change direction quickly and efficiently(8). Additionally, reactive drills (drills where athletes respond to visual or auditory cues) add to decision making and reaction time(9).
Strength and conditioning programs are also crucial. Exercises that build lower-body strength, such as squats, lunges, and deadlifts, provide the power needed for explosive movements. Core stability exercises are essential for maintaining balance and body control during rapid changes in direction.
The Relationship Between Speed, Agility, and Injury Prevention

Speed and agility both improve performance and decreases risk of injury among athletes. Injuries are associated with poor agility, and poor neuromuscular control, especially in the lower limbs(10). Joint stability and coordination are improved with agility training and can better protect athletes from sprains, strains and other injuries(11).
For example, studies have demonstrated that athletes who complete agility-based training programs are at a lower risk of developing anterior cruciate ligament injuries(12).
Conclusion

Athletes need speed and agility to perform, to be fit and prevent injury. Targeted training methods such as sprint drills, plyometrics, and strength conditioning can help athletes improve their speed and agility. These fundamental skills will continue to be better understood as sports science evolves, and help athletic training and performance.

References
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