Why Sodium Matters More Than You Think in Long Races

Ask most runners what they need in a long race, and they’ll say carbs or water, and often sodium. And when cramps strike, dizziness kicks in, or your stomach refuses to absorb more fluid, sodium is usually the missing piece.

What sodium actually does

• Fluid balance: Sodium keeps water where it needs to be — in your blood plasma and muscles. Without it, water just sloshes in the stomach or flushes out as urine.

• Muscle contraction: Every stride, pedal stroke, or step relies on sodium to help nerves signal muscles. Low sodium = misfiring signals = cramps.

• Preventing hyponatremia: Drinking lots of plain water dilutes sodium levels. That can lead to nausea, confusion, and in extreme cases, medical emergencies.

How much sodium is enough?

Sweat sodium losses vary wildly. Some athletes lose 400 mg/L, others over 1500 mg/L. Heat, genetics, and training all play a role. That’s why sodium guidelines are broad: 500–1000 mg sodium per liter of fluid.

Dirtbag Hydration is built with 400 mg sodium per serving. Why not higher? Because it gives flexibility.

• For light sweaters, 400 mg per serving is plenty — it keeps hydration balanced without putting unnecessary strain on the kidneys.

• For heavy sweaters, it’s a solid base you can stack. Add salt capsules, tabs, or extra sodium powder, and you’re easily covering high losses without having to overthink.

Why flexibility matters

Some brands cram 1000 mg sodium into every serving. That works for heavy sweaters, but for athletes with lower needs, it can cause GI distress, bloating, or even kidney discomfort over long efforts. Dirtbag’s approach is simple: start with a baseline, then adjust upward as needed.

Practical tips for race day

• Hot day, salty sweater? Carry extra sodium caps and take one every 30–45 minutes alongside Dirtbag.

• Cool weather, light sweater? Stick to Dirtbag alone and you’re covered.

• Unknown sweat rate? Test in training — weigh yourself before and after long runs to estimate fluid loss, and note if your clothes are caked in salt.

Bottom line

Carbs fuel the engine, but sodium keeps it from stalling out. Ignore it and you’ll pay with cramps, dizziness, or worse. Dirtbag Hydration gives you a flexible 400 mg sodium baseline — enough to keep most athletes balanced, adjustable for the ones who need more. Fuel smarter, sweat harder, finish stronger.