Arm pain in tennis: what your gear can actually do

If you are reading this with a sore shoulder, elbow, forearm or wrist, the first thing to say is this: pain that lasts, that wakes you at night or that interferes with everyday movements is a matter for a doctor or a physiotherapist, before any change of equipment. Nothing below replaces that advice.

What equipment can do is narrower, and real. It is not the cause of the pain: that is almost always a load the body no longer absorbs — a volume of play, a stroke, a return to the court that came too fast. But equipment adds to or removes from the load on an arm that already has too much, and two things are worth knowing straight away: the most effective lever is not the racquet, it is the string — and a lighter racquet often makes things worse rather than better.

This article covers the whole upper limb, because the chain is the same: what travels back from the string bed passes through the hand, the wrist, the forearm, the elbow and then the shoulder. If the diagnosis is lateral epicondylitis, it has its own article, more detailed on that one point: tennis elbow and your racquet.

What happens in the arm, in one image

At impact, the ball forces a sudden deformation on the frame. Part of that energy leaves with the ball, part stays in the racquet as vibration and recoil, and a fraction travels up into the hand, the wrist and the forearm.

Anything that lengthens the contact and anything that absorbs energy reduces that fraction. Anything that shortens the contact and returns energy quickly increases it. That is the only principle to remember, and it orders everything else.

The levers, in the order they count

• The string — the strongest of all. A stiff monofilament transmits considerably more than a multifilament, all else being equal. Cost: one restring.

• The tension — strong. Dropping tension lengthens the contact and softens the launch. Cost: nothing extra.

• Mass and inertia — strong, and against intuition. More mass absorbs better. Cost: some lead.

• Frame stiffness — real but slow to correct: it means changing racquet.

• Grip size — moderate. A handle that is too small makes you squeeze, and squeezing tightens the whole chain.

The order matters: the first lever is also the cheapest and the fastest to try.

The string, first

It is the only part that touches the ball, and it decides how the shock is damped. A stiff monofilament — the most widespread family today, because it holds up to heavy hitting and spin — deforms little, returns energy fast, and transmits more. A multifilament, or a string with more generous elongation, deforms for longer under the ball and gives back more gently.

That is why our range is numbered in order of measured elongation: from N°1, the softest and most generous in return, through to N°7, the stiffest and most predictable. When an arm complains, we always look towards the N°1 and the N°2 — and never the N°7.

One detail that weighs more than people think: a stiff string ages badly. It loses its elasticity long before it breaks, and a racquet strung six months ago with a monofilament hits harder than it did on day one. It is the first thing to rule out, because it costs no more than a restring.

Then the tension

Dropping tension lengthens the contact and softens what travels up. Two or three kilos less is felt immediately, costs nothing extra, and can be tested at the next restring.

One honest limit, though: every string has a useful range beyond which loosening changes little in the stringbed and starts to cost control. Going down indefinitely is not a strategy.

A lighter racquet does not spare the arm

It is the most common reflex, and most of the time it is a mistake. When the arm hurts, people instinctively look for a lighter racquet — since weight is tiring.

But the weight that tires the muscle and the mass that absorbs the shock are not the same business. A light frame is pushed back by the ball more than a heavy one. It recoils faster at impact, it vibrates more, and it transmits more energy to the wrist. Mass, on the other hand, takes it: it opposes its inertia to the ball instead of giving way.

A lighter racquet tires the arm less over two hours, and mistreats it more on every shot.

So the right setting is not as light as possible. It is the highest mass your stroke can carry without arriving late — and not one gram more, because a racquet you can no longer swing produces a degraded stroke, which does damage of its own. That balance can be tuned, and tuned finely: a few well-placed grams change the inertia without making the racquet unmanageable.

Those few grams can be worked out before they are added: the configurator asks six questions and returns a mass, a balance and a swingweight, to be applied to the frame you already own.

Frame stiffness

A stiff frame deforms little and returns energy quickly: the ball leaves early, the trajectory is predictable, and the arm takes more. A softer frame absorbs part of the shock in its own deformation.

That does not mean stiffness should be avoided — a very soft frame requires you to produce all the energy yourself, which is another form of load. The right answer is in between: neither soft enough to force you, nor rigid enough to send the shock straight back into the arm.

In what order to change things

1. Restring, if the string is more than two or three months old. On its own, that step settles a fair share of cases.

2. Change string family before changing anything else — towards softer and more elastic. Biggest effect for the smallest price.

3. Drop the tension by two or three kilos at the same time, or just after.

4. Look at mass and inertia, and correct if the racquet is very light or very manoeuvrable. Check the grip size while you are at it: too small and you squeeze, and squeezing tightens the whole chain.

5. Consider the frame last — it is the slowest and most expensive lever.

One rule of method that applies throughout: change only one thing at a time. If you change the string, the tension and the racquet on the same day and things improve, you will not know why — and you will not know what to repeat next time.

What gear will not do

It will not repair a tendon, it will not correct a stroke, and it will not make up for coming back too quickly after a break. A softer string does not make an arm stronger: it removes load from an arm that has too much.

That is already considerable, and it is all one can honestly expect. If the pain persists despite these changes, or if it settles in, it is a healthcare professional you need to see — and the equipment will come in support of what they tell you, not in place of it.