Hydration for Florida Athletes: Why Water Alone Isn't Enough

Sweat isn't just water. It's water plus electrolytes — primarily sodium, along with meaningful amounts of potassium, chloride, and magnesium. When you sweat, you lose all of these together.

If you replace the fluid loss with plain water — no electrolytes — you're diluting the sodium concentration in your bloodstream. This is called hyponatremia (low blood sodium), and even mild cases produce fatigue, cramping, cognitive impairment, and the muddy feeling that so many summer golfers describe.

In extreme cases, hyponatremia is medically dangerous. But mild-to-moderate cases are far more common than most athletes realize, and they show up as poor performance and awful recovery even when the athlete is drinking plenty of water.

An 18-hole round of golf in July heat in Palm Beach County can produce sweat losses of 3 to 6 liters. A three-hour tennis session can produce similar losses. A morning cycling ride from Delray Beach north along A1A can push sweat losses even higher because of the intensity and duration.

Sodium losses in that sweat vary widely by individual — anywhere from 500 mg to 2,000 mg per liter — but the average for adults in hot conditions is around 800 mg per liter. So a golfer sweating 4 liters over 18 holes is losing 3,200 mg of sodium.

Filling three water bottles adds fluid volume but adds essentially zero sodium. The sodium deficit gets deeper as the round progresses.

For active adults playing sport in Palm Beach County's heat, a workable hydration strategy has three components:

Pre-hydrate the night before and morning of. Drink adequate water in the 12-24 hours before your activity. Include sodium — a normal meal with salt is fine, or an electrolyte drink if you sweat heavily. Aim to start the activity in a well-hydrated state.

Hydrate during the activity with electrolytes, not just water. For any activity longer than an hour in the heat, plain water is insufficient. Use an electrolyte solution — commercial sports drinks, electrolyte tablets in water, or homemade solutions with sodium and other minerals. Target roughly 500-1000 mg of sodium per hour of heavy activity, along with adequate fluid.

Rehydrate after with fluid, electrolytes, and food. The 30-60 minutes after activity is a critical window. Fluid alone isn't enough — you need to replace sodium and other electrolytes, and food helps the fluid stay in your system (rather than being urinated out immediately).

Commercial options vary widely in quality. Look for products with: - 300+ mg of sodium per serving (many mainstream sports drinks have far less) - Meaningful potassium (100+ mg) - Modest sugar or none, depending on your goals

Options that work well for most Palm Beach athletes: - LMNT (high sodium, no sugar) - Nuun tablets (moderate sodium, easy to carry) - Skratch Labs (sodium plus modest carbs for longer efforts) - Gatorade Endurance formula (higher sodium than standard Gatorade)

Homemade option — for those who prefer to control ingredients: 20 oz water, quarter teaspoon of sea salt, a small squeeze of lemon or lime, and a small amount of maple syrup or honey if you want some carbs. Cheap, effective, easy.

One factor that changes the equation: how heat-acclimatized you are. Snowbirds arriving in Palm Beach County in October have relatively poor heat tolerance for the first two to three weeks. Their sweat rates are lower and their sodium losses are higher (heat-acclimatized athletes sweat more but conserve more sodium).

For snowbirds specifically: expect to need more careful hydration in your first month back in Florida each season. Play shorter rounds, hydrate more aggressively, and be more conservative about heat exposure until your body adapts.

For year-round residents: your body is better adapted, but the losses are still significant. Don't let acclimatization make you complacent about hydration.

Heat illness is a real concern in Florida summer sport. Watch for:

• Muscle cramping — often the first sign of significant electrolyte imbalance

• Headache during or immediately after activity — often mild hyponatremia

• Dizziness or light-headedness on standing after activity

• Cognitive fogginess disproportionate to the effort

• Nausea during activity in the heat

Any of these warrants stopping activity, hydrating with electrolytes, getting out of the heat, and — if symptoms persist or worsen — seeking medical care. Heat stroke is a genuine emergency.

For active adults playing sport in Palm Beach County: plain water is inadequate hydration for anything longer than an hour in the heat. Electrolyte replacement is not optional — it's the difference between finishing a round feeling depleted and finishing feeling okay.

The correction is simple: replace what you're actually losing. Water alone doesn't do it.