Defining, Developing and Measuring Agility

Agility may be defined as the ability to change direction rapidly, without losing balance, using a combination of strength, power and neuromuscular coordination.7,8,12,17 Until recently, these types of definition have dominated and greatly affected the way in which agility is trained and tested. However, recent developments have questioned whether these definitions truly reflect the nature of agility in a sports context, and as such, new definitions retain these movements but also add a reactive element. For example, Young et al.,16 and Sheppard and Young13 also add that agility is further affected by the athlete’s perceptual and decision-making skills (see Caption 1 and Figure 1). What is not in question is that agility plays a major role in the performance of many sports and indeed, for team sports such as soccer9 and racquet sports such as tennis, agility may be the best single indicator of overall performance. The significance of these more recent definitions may be illustrated by the fact that many agility drills are pre-planned and therefore only assess an athlete’s ability to change direction (and not respond to a sport-specific stimulus). However, in most sports, a change in direction is produced in response to a stimulus such as an opponent’s actions, and is influenced by perceptual and decision-making skills.13,15,16 For this reason, the ability to change direction and speed in a pre-planned movement, such as that demonstrated in certain agility tests (e.g. T-test, Pro-agility, 5-0-5), may be better described as change of direction (COD) speed.15 Developing Agility As a consequence of this updated definition of agility, several tests and drills have been developed5,3 that require athletes to change direction in response to a stimulus such as a light, thus incorporating reaction time within the agility task. Again, this may not replicate on-field play as reaction time wil