How to Reduce Leg Cramps During and After a Dive

Leg cramps are one of the most common comfort issues divers face. They aren’t caused by one thing but by several small factors stacking up: exertion, cold, hydration, technique, and gear fit. This guide focuses on practical ways to prevent them before, during, and after the dive.

At a Glance

• Main Causes: overexertion, cold, hydration, finning technique, gear fit
• Fast Fix: stop, stretch the calf or hamstring, slow breathing, reset
• Best Prevention: hydration, warm-up stretching, efficient frog kick, proper trim

Leg cramps are one of the most common problems divers deal with, especially during long surface swims, current, cold water, or any dive that forces you to work harder than expected. Most cramps don’t come from a single cause. They appear when several small factors add up: fatigue, hydration, technique, workload, and gear fit.

Why Divers Get Leg Cramps

• Overexertion from current, long swims, or heavy gear
• Cold water tightening muscles and increasing workload
• Dehydration or low electrolytes
• Poor finning mechanics, especially straight-leg flutter kicking
• Tight or under-conditioned muscles
• Gear restrictions that reduce circulation or ankle mobility

Before the Dive: Reduce the Conditions That Lead to Cramping

Hydrate and Balance Electrolytes

Dehydration is one of the most consistent contributors. Drink water across the day, not in one big hit at the site. Add electrolytes to help maintain fluid balance. I personally use Skratch Labs the night before and again before the dive, but any balanced mix works.

Fuel Your Body

Don’t dive on an empty stomach. A simple meal with complex carbs and modest sodium is enough. You don’t need specialty foods unless you know something works for you.

Warm Up and Loosen Tight Muscles

Five minutes of stretching makes a real difference. Focus on:

• Calves
• Hamstrings and quads
• Ankle mobility

Check Gear Fit

Small gear issues create large problems underwater. Look for:

• Fins that are too tight or too stiff
• Boots that compress or bunch up
• Drysuits that restrict leg extension

During the Dive: Reduce Workload and Improve Efficiency

Use an Efficient Kick

Straight-leg flutter kicking is the most common trigger. A bent-knee frog kick reduces strain and gives better control with less effort.

Control Buoyancy and Trim

If your trim is off, your legs compensate constantly. Proper weighting prevents your fins from doing the work your buoyancy should be doing.

Manage Workload Early

• On long surface swims, roll onto your back and use a backstroke kick
• Inflate your BCD and rest before pushing through fatigue
• Ask for help early instead of after exhaustion sets in

If You Cramp Underwater

• Stop finning immediately
• Signal your buddy
• Stretch the muscle by pulling your fin tip toward your shin
• Slow your breathing and relax before resuming

If the cramp returns repeatedly, end the dive. Fatigue and elevated CO2 make recurrence likely.

After the Dive: Recovery and Prevention

Stretch Again

Light stretching clears tension from calves, quads, and hamstrings.

Rehydrate

Replace what you lost with water or electrolytes. If you’ve been eating salty snacks, water is usually enough.

Heat Helps (With Context)

Heat relaxes tight muscles. DAN has noted that heat applied immediately after diving may theoretically increase decompression stress, but by the time most divers reach a shower, that window has already passed. Use heat if it helps.

When Cramping Signals a Bigger Issue

• Circulation problems
• Nerve impingement
• Medication effects
• Nutrient deficiencies

If cramps appear outside of diving or persist despite good preparation, consider a medical evaluation.

Where I Am With This

I deal with leg cramps on many dives, especially in cold water or during long surface swims. There isn’t a single fix. What works for me now is simple:

• Hydration and electrolytes across the day
• Stretching before and after diving
• Building leg strength and mobility outside the water

It’s a work in progress. If you struggle with the same thing, you’re not alone. Preventing cramps usually comes down to reducing workload, improving technique, and taking care of the basics before you ever enter the water.