How to Avoid Leg Cramps During and After a Dive

Why Leg Cramps Happen While Diving

Leg cramps are a common annoyance for divers — especially during surface swims or finning against current. They're usually caused by a combination of:

Overexertion (especially in cold water)
Dehydration or electrolyte imbalance
Poor finning technique
Tight or under-conditioned muscles

For many of us, it’s not one cause — it’s several things stacking up.

Before the Dive: Set Yourself Up for Success

Hydrate Intentionally

Even mild dehydration can trigger cramping. Drink water and electrolytes — not just one or the other. Personally, I use Skratch Labs hydration mix 12–24 hours ahead of a dive day, then again right before diving.

Eat Smart

Don’t skip meals before diving. Aim for something that includes:

Complex carbs (for fuel)
A bit of sodium (to retain fluids)
Magnesium-rich or potassium-rich foods if you like — the old advice about bananas and cramps isn’t strongly supported by science anymore, but it’s harmless and may help some people.

Stretch and Warm Up

If you jump in with tight calves or hamstrings, you're asking for trouble. Spend 5–10 minutes doing:

Calf stretches
Quad and hamstring stretches
Ankle rolls

If possible, do these before suiting up.

Adjust Your Gear

Check for anything that restricts circulation:

Fins that are too tight
Boots that bunch up
A drysuit that pulls when you move your legs

Try different fins if you're consistently cramping — stiffer blades can fatigue your legs faster.

During the Dive: Stay Ahead of the Curve

Use Efficient Finning Techniques

Flutter kicking with straight legs is a cramp magnet. Instead:

Use a bent-knee frog kick (low effort, better control)
Keep movements smooth and small
Avoid rapid or panicked kicking

Control Your Buoyancy

Poor buoyancy means more finning to stay in position — and that leads to overworked legs. Fine-tune your weighting and trim so you’re not constantly correcting your position with your feet.

Watch Your Workload

Surface swims, current, surge, or towing gear can push your muscles past their limit. If needed:

Surface on your back and use a backstroke kick
Inflate your BCD and rest before continuing
Signal for assistance early instead of pushing through

After the Dive: Recovery and Prevention

Gentle Stretching

Take 2–3 minutes to stretch again after the dive — especially your calves, hamstrings, and quads. This helps flush waste products and reduce tightness.

Rehydrate With Electrolytes

Replace what you lost with another dose of electrolyte mix or just plain water if you’ve been eating salty snacks. Keeping fluids balanced is more important than forcing any specific drink.

Hot Shower or Warm Compress

Warming the muscles can relieve post-dive soreness or minor cramps — but there's a caveat. DAN has suggested that applying heat too soon (less than 30 minutes) after diving might increase decompression stress due to vasodilation. That said, unless you're diving right next to a hotel room, it’s highly unlikely you’ll get to a hot shower in less than 30 minutes. You'll probably be cleaning gear, logging dives, and debriefing — so the risk is low. And honestly, a hot shower after a cold dive feels so good.

When to Seek Medical Advice

Persistent leg cramps could be a sign of:

Circulation issues
Nerve impingement
Medication side effects
Nutritional deficiencies (like magnesium)

If cramps occur outside of diving or don’t improve despite taking precautions, talk to your doctor or a sports medicine specialist.

Final Thoughts

I’ve struggled with leg cramps on virtually every dive — especially during long surface swims or when using stiff fins. I haven’t fully figured out how to stop them yet, but I’m actively working on it. Right now, I’m focused on:

Staying on top of hydration and electrolytes
Stretching before and after dives
Building leg endurance and mobility with out-of-water exercise

We’ll see if it pays off. If you’re dealing with this too, you’re not alone — and it’s worth experimenting to find what works for your body.