This is an excerpt from Complete Conditioning for Hockey by Ryan van Asten.
Several factors influence change-of-direction speed and agility. These factors include physical, biomechanical, and perceptual and cognitive qualities.
The purpose of change-of-direction (COD) or agility exercises is to quickly change the body’s momentum to a new direction. Paul, Gabbett, and Nassis (2016) suggested that physical qualities represent the most significant determining factors of total time to complete an agility test. Although the ability to react to a stimulus, such as an opposing player, is essential, if the athlete does not possess the appropriate physical capabilities to perform the task, the cognitive abilities can never be realized.
Many scientific studies have highlighted the relationship between muscular strength and the ability to change direction. One such study demonstrated strong correlations between maximal dynamic strength; eccentric, concentric, and isometric strength; and COD performance (Spiteri et al. 2014). However, this same study noted that these factors did not influence agility performance when a cognitive or reactive component was present.
Since changing directions involves all three phases of muscle action (eccentric, isometric, and concentric), it has been demonstrated that improving these qualities alone will have a significant impact on the ability to redirect the momentum of the body in an organized manner. Spiteri et al. (2014) also highlighted the importance of braking capacity (eccentric strength) and suggested that eccentric strength is the main predictor of performance for COD tasks when the intensity and the total number of direction changes increases. Chapter 5 outlines in detail various strength training techniques that directly affect the COD ability.
On the other hand, training to improve power has also been shown to enhance COD performance. For example, Váczi et al. (2013) demonstrated slight but significant COD ability improvements resulting from a six-week plyometric training program. There is conflicting evidence regarding power training and COD performance, however. Tricoli et al. (2005) demonstrated that power training protocols such as weightlifting and vertical jump training improved vertical jump and sprinting performance but not COD performance. These authors suggested that power transfer to more complex agility tasks is difficult and could be influenced to a greater degree by motor control factors such as technique.
Like all dynamic sporting movements, COD and agility performance are governed by the athlete’s technical skills. The strength and power developed in the gym must be transferred effectively and efficiently to complex sporting movements to optimize the performance of these tasks. The gym setting is typically a more controlled environment with clearly defined actions; therefore, it is also imperative to train the sporting task’s technical skills. These technical skills must first be identified then progressively trained by increasing speed, complexity, and reactivity.
Coaches and practitioners should not begin training at the endpoint. Far too often, reactive agility training is the starting point when athletes do not possess the ability to perform simple tasks such as decelerating from a linear acceleration. These skills need to be broken down, beginning with slow and simple and progressing appropriately to fast and reactive. The end goal is fluid and efficient movement in the face of external stimuli.
Perceptual and Cognitive Qualities
Perceptual and cognitive qualities come into question when reactivity and decision-making are added to a task or during a game or practice. The majority of the scientific literature on strength and power training and its effects on COD and agility focuses primarily on predetermined skills. The literature that does examine agility often demonstrates that strength and power training have negligible performance benefits. This fact is due to the perceptual, cognitive, and decision-making skills necessary to react to a specific stimulus and optimize agility. Coaches often attempt to train reaction time; however, real-time agility during a game is far more complex. Data suggest that the most agile athletes in a game or competition exhibit more accurate and faster responses due to their capacity to anticipate what will happen (Roca et al. 2011). This anticipation comes by recognizing the opponent’s postural orientation, recognizing structure and patterns in game situations, and correctly predicting what the opponent is going to do. Roca et al. (2011) also studied the visual patterns between skilled and less skilled soccer players and found that the skilled players’ visual searching during play was more abundant and shorter. The skilled soccer players also alternated their visual fixation more frequently between the player in possession of the ball, the ball itself, and other game play areas. These data highlight the importance of information gathering and processing on agility performance.