The Science of Sodium: Customizing Your Protocol (Part 2)

Most off-the-shelf hydration powders list only 300 mg to 500 mg of sodium per serving, well below the 800 mg to 1000 mg per hour starting point from Part 1.

Doubling your scoops to close that gap is not the answer. It raises carbohydrate concentration, which slows gastric emptying and can cause the bloating and gastrointestinal distress you are trying to avoid. Here is how I adjust a drink instead.

Add sodium to your usual mix. Check the label for sodium per serving, then add a fraction of a teaspoon of sea salt or unflavoured sodium citrate to your usual powder. This raises sodium without raising carbohydrate concentration. I use BioSteel sport hydration mix as my base.

Mix it into your flask or packet. I do not recommend salt capsules. Concentrated sodium swallowed without enough fluid can irritate the gut, and a capsule is harder to adjust than a drink. Instead, add the sea salt to your hydration mix and reach your target ratio directly in your flask. For long runs and races, I measure custom ratios into individual packets ahead of time so you control exactly what you take in.

Train your gut from week one. Your gastrointestinal tract adapts to repeated intake of fluid and carbohydrate, so you cannot expect it to handle large volumes and higher sodium concentrations for the first time on race day. All Team Redde Endurance rostered athletes begin gut training in week one of their plans.

Read your own signs. Sweat rate and sweat sodium concentration are individual. White, salty residue on your skin, clothing and hat suggests you lose more sodium than average and may need the upper end of the range. Swollen fingers can occur in the heat. If you also gain weight across a long session or feel bloated, you may be drinking more than you sweat, so review your fluid intake. Weighing yourself before and after a long run is the simplest way to estimate your sweat rate.

Never test a new sodium plan on race day. Use your weekend long sessions to adjust ratios and build a gut that tolerates them.