How Your Tennis Strings (and Grip Size!) Could Be Causing Your Injuries

Ryan Choi, PT, DPT, FAFS

When tennis players talk about injuries, the usual suspects pop up: bad technique, overtraining, the courts, or just plain old bad luck. But there’s one factor that many miss... your strings and grip size. Your strings and your grip work together in ways that can seriously affect your arm health. Let’s break it down and we’ll talk about when it’s time to see a physical therapist too.

Strings: Not Just About Power and Spin

Choosing tennis strings isn’t just about spin and power — your strings are your racket’s shock absorbers. The right setup can protect your arm, while the wrong one can overload your tendons and joints, fast.

The String Breakdown

Here’s a quick look at the main string types and how they treat your body:

• Natural Gut – The gold standard for comfort. Super soft and arm-friendly, but expensive and not the most durable. Great if you’ve had elbow or shoulder issues.

• Multifilament – A more affordable, synthetic version of natural gut. Still soft and comfy — a great middle-ground for recreational players.

• Polyester (Poly) – This is the “performance string” you see a lot of pros using. It’s stiff, durable, and great for control, but it’s also tough on your arm — especially if you string it tight.

• Synthetic Gut – Kind of a jack-of-all-trades string. Not too soft, not too stiff. Works well for casual players who want good performance without risking their arm.

How Strings Can Affect Your Arm

1. Stiffness = More Shock

Stiff strings (like polyester) don’t absorb much vibration. That shock gets sent right up your arm, which can lead to tennis elbow (that dreaded pain on the outside of your elbow) or even shoulder issues.

2. Tension Matters

Even if you have comfy strings, stringing too tight reduces their shock-absorbing power. Lowering your tension a bit lets the strings flex more, which can protect your arm from the constant vibration.

Rule of thumb: If you’re feeling soreness, drop tension by a few pounds and see if it helps.

3. Old Strings = Trouble

Even the best strings lose their bounce after a while. Old, dead strings don’t absorb shock well, which means more stress on your arm every time you hit.

Don’t Forget Grip Size!

Strings are just part of the equation — your grip size plays a big role too. If your grip is too small, your hand must overwork to keep the racket stable, which can strain your wrist and forearm. If your grip is too big, your arm gets stiff and you lose flexibility, which can lead to shoulder troubles.

Quick Grip Check

Here’s a simple way to check your grip size:

• Hold your racket like you normally would.

• See that gap between your fingers and your palm? You should be able to fit your index finger from your non-hitting hand right in that space.

• If the gap is way too big or way too small, your grip size might be off — and that’s putting unnecessary strain on your arm.

The Winning Setup for Injury Prevention

Player Type	Suggested String	Recommended Tension	Grip Size Tip
Arm Injury Prone	Natural Gut or Multifilament	48-53 lbs	Make sure you can fit that index finger!
Power/Advanced Player	Hybrid (Poly mains, Multi crosses)	50-55 lbs	Check grip, especially if you use overgrips.
Casual Player	Synthetic Gut or Multifilament	50-55 lbs	Get your grip size right from the start.

Still Hurting? Time to See a Physical Therapist

Working with a tennis-savvy physical therapist can do wonders for your game — and your long-term health. Physical therapists are trained to pinpoint the root causes of pain, whether it’s from muscle imbalances, overuse, or even how you’re swinging.

We’ll create a personalized plan to correct muscle imbalances and build strength where you need it most, so you can play with more power and flexibility. Plus, we’ll teach you movement and strengthening exercises that actually make sense for tennis players.

Physical therapists also use hands-on techniques (manual therapy) and other modalities to improve mobility in key areas like your shoulder, elbow, and wrist — all the joints that take a beating on court.

And here’s the thing: you don’t have to be injured to see a physical therapist. Think of it as a tune-up for your body, the same way you string and adjust your racket to keep it in top shape.