What's Up With Deceleration?

Why Athletes Need To Train Deceleration

If someone were to ask you what is more important for a basketball player, a big vertical jump or the ability to land that vertical jump in a good position, what would you say?  Often times, coaches and trainers are focused on their athletes being able to jump high and sprint fast because that is what is noticeable and pops to the untrained eye in sport. While being able to jump and accelerate is great for athletes, being able to control the landing is an essential, and often neglected component for preventing injury and increasing performance.

Deceleration occurs frequently in sport when an athlete is jumping, cutting, changing direction, tackling and so on. Think about a receiver sprinting and then having to make a cut to complete the route. The athlete will need to decelerate enough to make the cut and then accelerate to complete the route. This is done primarily through flexion of the hip, knee, and ankle that allows them to reduce the force. This reduction of force not only requires strength in the legs and trunk but also body control and awareness. 

The problem with neglecting training deceleration is we are equipping our kids with Corvette engines and then giving them Prius brakes. This is why the rate of ACL injuries has increased by 400% in the last 10 years for young athletes. (3) In one study looking at causes of non-contact ACL injuries, videotape reviews showed ACL injuries for female athletes often occurred during a simple deceleration maneuver (1). If we know that ACL injuries are increasing and poor deceleration is an indication of injury, it stands to reason that it needs to be trained and taught in a controlled environment. In doing this, we can better prepare athletes for success in the unplanned and reactive environments that happen in sport.

So, what happens if athletes don't have the required strength and control to properly decelerate? First, we will see a breakdown in their movement. One of the more common breakdowns is the knee abducting (valgus). Studies have shown that valgus movements when landing are a risk factor for non-contact ACL injuries, and training programs that reduce knee valgus reduce the risk of ACL injuries (1). 

Next, from a performance standpoint, if the athlete does not have the required strength and control it is common for the hip, knee, and ankle to experience a longer range of motion with too much flexion. This will reduce the athlete’s ability to produce force quickly after the deceleration and the transition from deceleration to acceleration will happen too slow. Reactive strength (being able to absorb force and rapidly accelerate) is critical for multi-directional speed and agility that is necessary for the sport. As we all know being a step or two behind an opponent can make all the difference. 

Now that we understand the benefits of controlling the deceleration phase for reducing injury and increasing performance how do we train it? 

First, establishing a base level of strength through squatting, lunging, stepping up, and rotating the trunk is critical. Following a linear progression that includes these movements each week will allow young athletes to build the requisite strength that is required to move well in sports. It is essential that these movements can be done properly with a load in a controlled environment because they mimic the movements you perform on the field, court, or track. Forces absorbed by the body are much greater in a sport-like reactive environment. (2) Basically, if we cannot establish a proper base level of strength and control in these positions in a closed environment it is unrealistic to expect our athletes to handle it in an open sport environment leaving them susceptible to injury. 

Second, we need to learn to maximize the stretch-shortening cycle. The stretch-shortening cycle happens when the muscle lengthens (eccentric action) providing a stretch load that will increase force production when the muscle shortens (concentric action) (2). The stretch-shortening cycle can greatly enhance force production when used right. 

Real-world ways to train the stretch-shortening cycle include a variety of plyometric exercises. Depth drops are a great tool for reinforcing landing mechanics and teaching athletes to properly absorb force. As they gain strength and display competency in landing and absorbing force they can progress into completing another task directly after the drop like a vertical jump, lateral jump or sprint. This sequence trains what we see in sport when deceleration is required followed by rapid acceleration. 

Overall, having a big vertical jump or being fast is great for an athlete, but if they don’t have the strength to put on the brakes and reduce force in a controlled fashion there is a greater chance of injury. A combination of acceleration and deceleration training is crucial if we are going to maximize athletic potential in all levels of athletes. 

1.Boden, B. P., Sheehan, F. T., Torg, J. S., & Hewett, T. E. (2010, September). Noncontact anterior cruciate ligament injuries: mechanisms and risk factors. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3625971/)

2. Speed, D. (2017, May 1). Effective Deceleration Technique for Court and Field Sports. Retrieved from https://www.nsca.com/education/articles/kinetic-select/effective-deceleration-technique-for-court-and-field-sports/

3. Reporter, D. (2019, November 29). Rate of young athletes needing ACL surgery has risen 400% in 10 years. Retrieved February 27, 2020, from https://www.dailymail.co.uk/health/article-7739051/Rate-young-athletes-needing-ACL-surgery-risen-400-10-years.html?ito=facebook_share_fbia-top&fbclid=IwAR3Kr6D0ct8vAkWU2jU99YP7Enlrxg5qPfWxkLkFQu1KSC7BT2jstlpVICc