Analyzing the biomechanics of an effective tennis serve is a fascinating endeavor. Although many components seen in traditional throwing analysis can be seen within its service motion, several aspects may differ slightly.
However, many players mistakenly believe they must rotate/turn their body forward as they serve, however this doesn’t work as the service motion works mostly on momentum transfer.
Stance
To develop an effective tennis serve, it’s crucial that you begin by assuming a proper stance. An ideal position involves sideways facing your court with feet shoulder-width apart and nondominant foot (left for right-handed players) at approximately 45-degree angles toward the net. Once in this stance, bend knees and drive off of the ground in order to create vertical linear momentum which will help your racket accelerate toward contact with ball quickly. Keep arms loose for optimal results as tight arms slow racquet down while tightness can even cause power losses!
Leg drive is another essential step. Your legs and hips (accelerators) form part of the kinetic chain and when operating at maximum capacity you will generate more power for each stroke. To do this effectively you must ensure sufficient force through ankles and knees to achieve this result.
Once your stance and leg drive are secure, you can focus on synchronizing upper body rotation with lower body movement – one of the primary challenges of adding power to one’s serve. Many players resort to using their shoulders or arms alone in swinging the racquet around, which works if done with control – however to speed it up you must put more force in legs and hips for this to happen at top speed.
Mastering a serve takes years of dedication and practice, but even recreational players can gain much benefit from following these simple steps and drills. By sticking to them, your serve can become stronger on the court! Just remember it won’t happen overnight — but in time it will definitely pay off! Thank you for reading – Peter Fryer of Love Tennis Blog
Cocking Stage
Successful tennis serves depend heavily on an effective cocking stage, or “cocking phase”, in which rotational momentum of the lumbar spine is quickly reversed, creating what’s known as “corkscrew effect”, to transfer force from muscle segments of the dominant arm into force vectors of transmission. An athlete utilizes dissociation between pelvis and trunk (known as “X factor”) as potential energy to harness for their stroke; two foot positions used during cocking include foot-up technique and foot-back technique – the former producing greater vertical force than its counterpart.
At this stage, the shoulder is in maximum external rotation and abduction, with its humerus elevated by approximately 100 degrees in frontal plane. This extreme position is accomplished through coupling between shoulder rotator muscles, trunk muscles and scapula contributions and shoulder external rotation produced by contraction of supraspinatus and infraspinatus muscles; for elevation purposes it also benefits from contributions by the rotator muscles of glenohumeral joint as well as posterior tilt of scapula muscles rotator muscles combine with contributions of trunk muscles and trunk/scapula contributions allowing the elevation of 100 degrees in frontal plane (Kibler, Chandler Shapiro & Conuel 2007).
Leg drive not only generates the necessary torque to cock an arm, but it also provides extra energy by pushing the racquet downwards away from the body – this counters any excessive amounts of external rotation occurring during cocking phase and prevents shoulder from reaching peak adduction at impact.
Cocking of arm and leg is achieved within less than one-hundredth of a second, due to highly efficient activation of muscles in shoulders and torso region. Furthermore, this phase is distinguished by minimal use of left erector spinae part, remaining this way throughout serve (Kovacs & Ellenbecker 2011).
Acceleration
At this stage, tennis players must apply force to both racquet and ball to change their state of motion and accelerate them. The greater the force applied, the faster and more powerful their serve. Muscle action involving latissimus dorsi, pectoralis major, and deltoid generates this force change needed in both objects’ states of motion change.
Effective delivery of force necessary to accelerate racquet and ball requires an effective combination of leg drive during loading phase and high degree hip rotation during cocking phase, along with maintaining an appropriate foot position that stores energy for acceleration phase of serve.
When serving at excessive speeds, tennis players need to ensure they generate sufficient power without jeopardizing their body and risking injury. Excessive forces required to accelerate both racquet and ball to such high speeds could result in overuse injuries such as shoulder, elbow or wrist strains.
To avoid such injuries, players should train effectively with exercises like plyometric training that improve their ability to decelerate quickly at high velocities.
Studies have demonstrated that the efficient production of angular momentum by the trunk plays a significant role in determining the velocity with which racquet hits ball. This is mostly due to how quickly trunk moves during this phase and therefore must produce large amount of angular momentum within a limited amount of time.
Studies have also demonstrated that when the speed of the racquet at which the ball is struck increases, its coefficient of restitution decreases due to energy lost through sound and heat transmission upon impact with it.
Follow Through Stage
The tennis serve is a complex movement involving many body segments, muscles and joints. As one of the key elements in a game of tennis, its execution requires great skill from all involved. To be effective, players must hit the ball at high speeds with precision while combining different phases to produce maximum power; thus making achieving consistency difficult to accomplish without proper technique. Only the greatest tennis players have such consistency with their serve technique.
The key to an effective cocking phase of serving lies in its loading stage (stage 3). To reach this goal, large amounts of kinetic energy must be generated in both upper and lower trunk muscles in order to generate significant axial rotation, torso elevation and shoulder flexion while activation of the rotator cuff muscles is essential – all these actions play a vital role in determining direction and speed of ball which impacts service velocity (Kovacs & Ellenbecker 2011b).
Once the loading stage has been completed, the cocking position should remain constant throughout acceleration and deceleration stages. Meanwhile, arm angular velocity increases during these steps to help move the racket toward its target further away. At the conclusion of deceleration stage glenohumeral internal rotation and forearm pronation continue until point of contact has been reached.
Acceleration and deceleration during this phase results in large eccentric loads on both upper and lower trunk muscles, particularly those belonging to erector spinae muscles. This occurs due to arm lengthening during cocking and acceleration stages which increases rotational forces at elbow, wrist and hand level.
Follow through is an indicator of a quality serve, yet learning it from watching other players may not be so straightforward. To better comprehend its movement and muscle recruitment requirements for optimal follow through performance, using mirrors or video recordings of yourself performing can be extremely helpful in learning this technique. This allows you to focus on all the movements necessary for an excellent follow through performance.