A few weeks back I wrote an article about strength training for tennis. More specifically, I wrote that physical training for tennis should stop focusing on “fancy drills” that may appear useful on the outside. Among other qualities (not the focus of this article), physical training for tennis should include a properly planned and executed strength training protocol. In this post, I’m going to outline the mechanical demands of tennis - this will hopefully provide a better understanding as to why strength training is important for tennis. And a brief application of strength training will be linked to each tennis demand to provide further context.

NOTE - There are physiological demands as well - and although related to the mechanical demands, for simplicity, we’ll assume they are independent of each other.

Physical Qualities For Tennis & The Influence of Strength Training

Tennis Demands Explosiveness

I don’t think anyone will argue that the modern game is characterized by explosive movements. The pace of the game is faster than it’s ever been, which means players need powerful movements to get to the ball. Research indicates that these movements are almost all within 3m of each other and a 3 set match may demand up to (or more than) 500 of these explosive bursts (Kovacs 2006). Exceptions to the 3m movements may include running down a drop shot or running for a wide ball.

How does strength training apply?

Performing maximal or near-maximal resistance training elicits neuromuscular adaptations. Basically, your nervous system becomes more efficient at recruiting, firing and synchronizing the appropriate muscle fibres, specifically type 2 fibres (the ones that are important for generating speed and power). That said, there may still be a by-product of muscle growth (hypertrophy), something that shouldn’t be a concern as the benefits of being more explosive surely outweigh the costs of being slow.

Tennis Requires Motion in Multiple Directions and Planes

Tennis is a multidirectional sport - a player will move forward, backward, laterally etc. It’s also a multi-planar sport. There are 3 planes of motion (figure 1) - sagittal, frontal and transverse. Tennis demands movement in all of these planes at different times. Every time you hit a groundstroke, you’re working the transverse plane (i.e. you’re rotating). When moving laterally or lunging to the side, you’re working in the frontal plane. Finally, when moving forward or volleying, you’re moving in the sagittal plane.

Figure 1. Source

How does strength training apply?

Working in a the weight room allows coaches to have more control over the environment. It’s possible to place the athlete into different situations where they need to work on a specific movement, and in a specific direction. For example, tennis players may have poor mobility and strength when moving laterally. A simple exercise like a side lunge can have a tremendous impact on a player's lateral movement while simultaneously working on increased range of motion in that specific pattern - especially when there’s an emphasis to continuously increase range with overload. Players need to be cautious - performing too many exercises in a certain direction or plane while neglecting others will make them good at those movements ONLY. This is the principle of specificity at work (something we’ll get to in another post).

Acceleration, Deceleration & Change of Direction in Tennis

It shouldn’t be a surprise that tennis requires great acceleration and change of direction (COD) abilities. When reacting after a split step, the aim is to accelerate to the ball as quickly as possible in order to get set-up effectively. The better your position when you set-up, the better your chances of hitting a quality shot. After every shot in tennis, a player must recover to be better prepared for the next ball. Change of direction ability has a big impact on an effective recovery. This is quite obvious for most players and coaches. What perhaps is not as obvious is a player’s ability to decelerate quickly and effectively in order to be set for the oncoming shot. While acceleration and change of direction require a tremendous amount of strength and power generation (to impart force into the ground and displace your body), deceleration requires a great amount of force absorption (to stop your body while it’s in motion).

To test explosiveness, acceleration, COD & more, check out the following 2 posts:

--> Testing in Tennis Part 1
--> Testing in Tennis Part 2

How does strength training apply?

Think of a squat. When you’re lowering the squat, this is effectively the deceleration phase - can you handle a high amount of load under control and then use strength, elastic energy etc. to lift the load back up? The ‘lifting back up’ is the second component of the squat; the acceleration/change of direction portion. At the most basic level, the more force you can absorb and then impart into the ground, the better will be your ability to accelerate, decelerate and change direction.

Tennis Demands Varying Joint Angles & Muscle Actions

Tennis requires a player to perform all kinds of movements. These include but are not limited to: bending forward and backward, reaching in all directions, lunging, squatting, twisting, flexion and extension of the elbow, shoulder and wrist etc. All of these actions have varied angles of flexion, extension, pronation, supination, abduction, adduction etc. at different joints, depending on the specific requirements during a point.  All of these movements will also necessitate differing muscle actions. Not to mention that velocity of each movement will differ at each joint.

QUICK ASIDE - For the younger generation of players reading this, there are 3 types of muscle actions: 

Concentric muscle action - the muscle shortens against an external load (ex: the upward/lifting motion of a squat or bicep curl).

Eccentric muscle action - the muscle lengthens against an external load (ex: the downward or lowering motion of a squat or bicep curl).

Isometric muscle action - the muscle contracts but there is no change in length against an external load (ex: think trying to lift a weight that’s just too heavy, you put all your strength into it - muscles contract - but the weight doesn’t move).

How does strength training apply?

Let’s use the serve to illustrate this point. When you’re beginning the service motion, you bend your legs, rotate your torso, extend your spine and externally rotate your shoulder. These are the main actions and all are performed eccentrically. Once you begin propelling your body with your legs, uncoiling your trunk, flexing your spine, internally rotating your shoulder, pronating your forearm and flexing your wrist at contact - you’re performing concentric muscle actions. Oh and when you land on your front leg after the serve, guess what? You first absorb the landing eccentrically and then stabilize your body isometrically (i.e. for a moment in time you’re contracting your leg but nothing is moving, not you, nor the ground from your landing).

Overhead & Rotational Strength & Power Are a Must for Tennis Players

Hitting big groundstrokes and serves, undoubtedly demands a strong, powerful lower body - and in today’s game, it’s almost a prerequisite to have a big serve and forehand. Guys like Raonic and Isner routinely hit serves in the 130s and even the smaller guys like Goffin and Ferrer can get their serves up into the high 120s. And the women are becoming more and more athletic as well with players like Azarenka and Kvitova hitting serves between the 110-120 mark and Serena being able to hit in the 120s in a routine like fashion.

How does strength training apply?

You may have the strongest legs in the world, but if there’s a leak in the chain - from legs, through the trunk and shoulder, there’s no way you’ll be able to get pace on the ball. Rotationally, it’s important to have strength and power so it can be transferred into the groundstrokes. The shoulder must have both power qualities for high speed bombs, and it needs to be able to handle the large forces that are being imparted on it with each ball strike.

Tennis is Demanding, Strength Training Can Prevent Injury

A tennis match is unpredictable. Match time, point length, ball direction from opponent, weather conditions, opponent style of play, playing surface etc. are all factors that can vary and may be out of a player’s control. This adds an interesting dynamic to any match - you don’t know how long you’ll be out there and what kind of shots will be expected of you. The tissues (bones, ligaments, tendons, muscles, fascia etc.) have to be able to handle the repetitive nature of the sport. If the force being imparted on your rotator cuff, for example, is greater than what that tissue can handle, injury will eventually ensue, this is a fact. And just because there’s no signs of pain now, does not mean that everything is fine and dandy. Proper strength training, working through all movements, muscle actions, joint angles etc. will offer the support the tissues need to minimize injury risk.