Tennis players must execute shots while decelerating as part of a change of direction. Many methods of testing and training change of direction fall short of accurately capturing tennis’ specific demands.
Most methods of testing and training change of direction (CoD) have two significant short-comings. First, they include a disproportionate amount of linear running. A change of direction breaks down into three components: deceleration, the directional change and acceleration. On either side of this sequence the player is moving at their speed and direction of play. Over-emphasizing linear running opens the door for an athlete’s acceleration and speed to mask his deficiencies in executing a change of direction.
Second, the tests are not sport-specific. They assess an athlete’s ability to change direction over durations, distances and angles she would not encounter in a competition.
Change of direction testing and training in tennis are particularly susceptible to these flaws. In many ball or court sports, the athlete changes direction in order to position himself for an upcoming task. They move towards or away from the ball or an opposition player to attain optimal position for a pass, shot or simply to create space for another player. However, the critical task in tennis – hitting the ball – overlays the deceleration and the directional change.
“The last step of a change of direction is always a lunge,” says tennis coach Ali Ghelem. “One step before the lunge you need to have the eccentric strength to decelerate the body. You must be good at decelerating before you bother with speed. If you come in with higher speed or more load from focussing your training on linear speed or building muscle mass, you have to be able to handle that increased momentum. Otherwise you lose more time in deceleration than you gained from getting there faster.”
Because most change of direction assessments do not separate out the three components, a “fast” tennis player in the testing lab could be slow on the court. These assessments also confine the tests to angles and movements that are not realistic – or at least not prevalent – during a tennis match. Most change of direction tests involve forward or lateral running, and changing direction 45, 90 or 180 degrees. They also include a non-tennis specific range of total distance, distance between changes of direction and total number of changes.
Tennis players can change direction between two and 15 times per point, with 70% of rallies containing four or fewer strokes, according to tennis strength and conditioning coach Matt Kuzdub. A singles player covers an area approximately 12 meters in each direction. Unless she is in a severely defensive posture, she will travel a much shorter distance between each change of direction. All aspects of training and testing should reflect those situations.
Kuzdub is presenting his work on change of direction training in tennis at the Women’s Tennis Coaching Conference in New York City. Kuzdub’s presentation will lay out how the different stages of a change of direction movement apply to tennis, and how to train performance at these key junctures. He emphasizes the importance of developing force in a variety of angles, the role of training through a range of joint angles and the neuromuscular elements that create a reactive split step.
“Tennis is different than other sports given the high rotational demand between changes of direction,” Kuzdub says. “Players need to absorb and apply forces across all planes of motion while executing the change of direction. A lot of training that you see has no real appreciation for that combination.”
Testing and training change of direction with 1080 Sprint
Kalle Granath coaches some of Sweden’s top professional soccer players and youth prospects. Granath uses the 1080 Sprint for change of direction training, sometimes in combination with FitLights to create multi-directional, sport-specific movement patterns. Granath can set the FitLights to cue an athlete through a known pattern, or he can randomize them to tap the perceptual-cognitive aspects of in-game change of direction.
The 1080 Sprint provides a unique way to train an athlete’s deceleration going into a change of direction. If the athlete is moving towards the 1080 Sprint – either forward or laterally – when they are cued to change direction, they must decelerate against the 1080 Sprint’s assistance. This creates an eccentric overload, which is immediately followed by a concentric stimulus as they accelerate away from the 1080 Sprint against resistance. Conversely, if they decelerate while moving away from the 1080 Sprint the resistance helps them reduce their forward movement. It then creates an overspeed first step as they come out of the change of direction.
“The assisted phase takes advantage of the stretch-shortening cycle. We go from the base of controlled patterns that can optimize a movement to making fast decisions in erratic patterns,” Granath said.
Tennis is particularly well-suited for change of direction training using the 1080 Sprint, given the distances involved and the patterns of play. Placing the 1080 Sprint outside the doubles court can the train the athlete’s acceleration and deceleration across the baseline. Depending on which side of the court the 1080 Sprint is on, the training will target deceleration with simultaneous rotation going into a forehand or backhand, and then recovering against resistance.
Similarly, setting it behind the baseline allows the coach to train the player’s movement towards and away from the net. The coach can set up scenarios such as serve-volley-volley-retreat, and progress the training from a purely conditioning scenario to hitting balls.
The output from the 1080 Sprint provides an accurate profile of each phase of a change of direction. More than that, the output goes beyond speed or time to complete the test. The output includes the athlete’s force and rate of force development. This accounts for the athlete’s ability to control his momentum, and can reveal when an athlete’s increase in muscle mass due to strength and power training is counter-productive for their ability to decelerate. Just as coaches develop a force-velocity profile for sprint speed, they can create similar profiles for change of direction ability.
Change of Direction Deficit: A More Isolated Measure of Change of Direction Performance Than Total 505 Time, Sophie Nimphius et al, Journal of Strength and Conditioning Research
Change of Direction and Agility Tests: Challenging our Current Measures of Performance, Sophia Nimphius et al, Strength and Conditioning Journal