This is my first full article since publishing my website, so I thought I'd share a paper I'd recently written regarding deceleration training in tennis and why it will benefit both coach and athlete coming into the spring tennis season - any feedback is also welcome.

Having worked in tennis for eight years as a technical coach, and four years within tennis conditioning, it's became fairly apparent to me that there's a piece in the puzzle that's missing in the average club/centre programme; knowledge on physical adaptation to players, injury prevention and specific physical training.

The first of these topics I'm writing about is training for deceleration, the ability to slow down and control force production. This is a training concept, from observing sessions and the lack of literature around the subject, seems to be something that has been completely forgotten about from a coaching perspective - unless at high performance level. The clear avoidance of this training puts an athlete at serious risk of injury with the sheer demand of force on the joints. I want to highlight to all players/coaches how important training for deceleration is and why it should be incorporated into your session plans.

If anyone has any questions or queries regarding how you can train for deceleration please feel free to contact me using the information provided on the 'Profile' tab.

Eccentric Strength Training to Improve Deceleration in Tennis

Strength training acts as the benchmark for both acceleration and deceleration training. This paper will focus primarily on the eccentric phase of strength training and benefits it can have in relation to deceleration and why, when applied correctly by coaches, it should not be overlooked.

Deceleration is defined as a “pre-cursor to a change in direction or a rapid drop in velocity in a minimal amount of distance or time” (Hewitt, Cronin, Button & Hume, 2011). This can be characterised by a sharp stop after a maximal sprint or when having to slow down to allow for changes of direction away from a straight line. Deceleration is often in response to an external factor such as a specific shot, movement or boundary line in that specific sport (Hewitt, Cronin, Button & Hume, 2011).

Hewitt et al. (2011) states deceleration is required after any sprint performance regardless of the relative velocity of the sprint, to slow the body’s center of mass (COM). The amount of time and distance allocated to slow the COM is dependent upon a wide variety of factors determined by the individual requirements of the sport (Hewitt et al., 2011).  In the sport of tennis for instance, the main influence will likely be the opposing players shot selection and the depth of the stroke.  These factors are especially critical given that on a tennis court the maximum sprint distance is approximately ten metres long, and given this short distance, maximal velocity will therefore not be reached.  Instead, the athlete in question will continuously be building velocity and for this reason the demands of deceleration on the joints in action can be tremendous.  Therefore, the training methodology applied, with correct technique, must replicate the demands of the forces required to maintain dynamic balance and effectively shift body weight into the next movement whilst also reducing the risk of injury.

For tennis players consistently partaking in regular competition, a high level of movement is required to accomplish success at junior events, British University and College Sport (BUCS) events, and professional level tournaments. Acceleration-concentrated training is common practice in strength and conditioning programmes for tennis players; but less focus is sometimes given to the importance that effective deceleration training plays in both upper- and lower-body movements of the tennis athlete (Kovacs, Roetert, Paul, Ellenbecker, & Todd, 2008). The lower body needs to perform large decelerations to prepare for and recover after groundstrokes, volleys, retrieving lobs to set up for an overhead and during the follow-through and on the landing phase of the serve. The upper body, particularly the muscles of the upper back and posterior aspects of the shoulder, feature the major muscles that help decelerate the upper limbs after ball contact in overheads, groundstrokes, and volleys. Kovacs et al. (2008, pg.3) states “A tennis athlete who can decelerate faster and in a shorter distance is an athlete who will not only be faster but will also have great body control during the tennis stroke”. Therefore, this greater control during the stroke will result in a greater level of dynamic balance (Kovacs et al., 2008).

Review of the Training Intervention

The four crucial components to effective deceleration are; dynamic balance, eccentric strength, power, and reactive strength (Kovacs et al., 2008).  The focus throughout this section will be analysing the strength training elements, and how they will benefit the tennis athlete and their deceleration capabilities when applied correctly.

As stated above, Kovacs et al. (2008, pg. 1) describes that it is “common practice” to focus training programmes towards acceleration, but fail to incorporate deceleration practice. When training or coaching an athlete for acceleration the focus is primarily concentric strength training, therefore the focus is on force production. With that said, to improve an athlete’s ability to decelerate, an athlete must be coached and trained to use their muscles in an antagonistic manner to be able to absorb that force.

This is where the focus on the eccentric strength phase of training is crucial. Not only does eccentric strength training promote an athlete’s ability to absorb the forces being generated more efficiently, but it also allows the athlete to prepare and react to the play quicker whilst also having the added benefit of being highly regarded to aid in injury prevention. Research states that humans can withstand 30% more weight eccentrically than concentrically (Ellenbecker, Davies, & Rowinski, 1988). Therefore, eccentric-focused strength training needs to be incorporated into an athlete’s periodised programme to make sure their strength gains are maximised. Taking this reasoning into consideration, the more force the athlete can withstand eccentrically during a general preparation phase should then be replicated into more specific training drills or act as a benchmark when moving onto more powerful exercises when the force demands are much greater. This will occur during a more specialised preparatory phase in their periodisation model and allow for a better deceleration, reduce the risk of injury and in turn hopefully put them in a greater position in competitive situations.

As the tennis athlete progresses and a sufficient eccentric strength base (as well as concentric) is established as mentioned above, this will then allow the athlete to progress onto more demanding training interventions where the force demands are considerably higher, power training for example. Having this ability to absorb large forces will stand them in a position where the chance of injury is substantially less and will lead to the greater strength adaptation. For example, in applied practice it is a foundational principle that before doing any form of power or plyometric training, an athlete must have a specified base level of strength. Despite the importance of this form of training there is seemingly a lack of information available for coaches in relation to eccentric training and injury prevention highlights an existing gap in the literature where more research is needed.

In relation to injuries, according to statistics gathered by the International Tennis Performance Association (iTPA) the lower body is the most frequently injured area in tennis players (ranging from 39-65%), followed by the upper body (ranging from 24-46%) the rest consisting of the head and trunk areas (Ellenbecker et al., 2009). A considerable amount of these injuries to tennis players are the result of inadequate eccentric strength, both in the upper body during the deceleration of the racket after serving, groundstrokes, and net-play as well as in the lower body during the deceleration of the body. Examples of when deceleration injuries occur due to potential insufficient eccentric strength may include when the athlete plants the feet to build a stable base for efficient stroke production or when reacting to the opponents shot selection, which then forces a change of direction. For instance, this could be the retrieval of a drop-shot which requires a fast acceleration forwards into the court and a sharp deceleration to prevent the athlete from touching the net or, when approaching the net and depending on the court surface, sliding into a shot.

These said injuries are most commonly going to occur due to the body not being able to absorb the forces that are required to perform that movement.

If the strength and conditioning coach prescribes, as suggested earlier in the text Kovacs et al. (2008), mainly acceleration type work while not enough spending enough time on deceleration training, it will result in an athlete who may have great initial velocity, due to a high level of concentric strength, but then will not be strong enough eccentrically to control the body to slow down fast enough before and/or after contacting the ball. This will result of this will be reduced on-court performance and may result in the increased likelihood of injury like the ones listed above due to insufficient eccentric strength (Kovacs et al., 2008).

As previously mentioned this topic hasn’t been greatly covered but it has been cited Kovacs et al. (2008) previously and the literature proposed states that most athletic injuries are the result of inappropriate deceleration abilities of athletes and an overemphasis of acceleration-focused (concentric specific movement) exercises both on and off-court.

Kovacs (2009, pg. 1) states that “Tennis players make an average of 4 directional changes per point but can range from a single movement to more than 15 directional changes on a very long point. In a competitive match, it is common for players to have more than 1,000 direction changes”.  Therefore, relating to the statistics above, efficient deceleration and eccentric strength is going to be required on each of these changes of direction to be able to prepare for the next ball. If the strength training programme that has been prescribed is appropriate the athlete should have the ability to decelerate at faster velocities in a sufficient time-frame and keep themselves under the needed control to make best possible contact with the tennis ball. The ability for the athlete to effectively decelerate is also important while transitioning into the recovery movement, this will allow them to be the ready position for the next shot earlier than say an athlete following a programme that is more focus towards acceleration.

To conclude this paper, tennis is a sport where high levels of agility and speed are required to compete at the highest level. Therefore, it is crucial that  as strength and conditioning coaches/practitioners we consider the physiological needs and force demands to perform these movements in an athlete’s periodised training plan in alignment with their training goals.

It is suggested in the literature that strength training is one of the fundamental building blocks of being able to both accelerate and decelerate. However, upon further investigation into current research, it’s it is implied that deceleration is not as highly applied or as focused on in training programmes as what acceleration is, and this attitude to coaching put’s the athlete at risk of not being able to maximise all their potential and could potentially lead to serious injury. The amount of force that is required to halt the body before changing direction can be highly demanding on the body, and for this reason an athlete must be strong enough to absorb this force, eccentrically, to allow for that next change of direction safely. With a higher level of eccentric strength, comes a much more efficient and lesser risk deceleration.

The constant need for changing direction to both attack and defend the court, determine opposing player’s shot selection and potentially environmental factors, requires a substantial amount of force to be able to stop the body before the next shot. Therefore, this paper proposes that eccentric strength training as a critical factor to any training programme for a tennis athlete, suggesting a greater emphasis should be placed upon eccentric training in both applied practice and in research.

References

1. With a higher level of eccentric strength, comes a much more efficient and lesser risk decelerKovacs, M. S. (2009). Movement for Tennis: The Importance of Lateral Training. Strength and Conditioning Journal, 31(4), 77-85. doi:10.1519/ssc.0b013e3181afe806
2. Kovacs, M. S., Roetert, E. P., & Ellenbecker, T. S. (2015). Efficient Deceleration. Strength and Conditioning Journal, 37(2), 92-103. doi:10.1519/ssc.0000000000000140
3. Hewit, J., Cronin, J., Button, C., & Hume, P. (2011). Understanding Deceleration in Sport. Strength and Conditioning Journal, 33(1), 47-52. doi:10.1519/ssc.0b013e3181fbd62c
4. Ellenbecker, T. S., Pluim, B., Vivier, S., & Sniteman, C. (2009). Common Injuries in Tennis Players: Exercises to Address Muscular Imbalances and Reduce Injury Risk. Strength and Conditioning Journal, 31(4), 50-58. doi:10.1519/ssc.0b013e3181af71cb
5. Fix the Brakes: Focus on Deceleration Training for Tennis. (2013, September 29). Retrieved August 20, 2018, from http://itpa-tennis.org/itpa-blog/fix-the-brakes-focus-on-deceleration-training-for-tennis