The complete guide to sodium bicarbonate for athletes.

Sodium bicarbonate is one of the most studied performance supplements in sports science. Over 40 years of research, hundreds of randomized controlled trials, and an official endorsement from the International Society of Sports Nutrition (ISSN) — and yet most athletes have never tried it.

The reason is simple: baking soda dissolved in water causes brutal GI distress. Nausea, cramping, bloating mid-race — consequences bad enough that most athletes who try it once never try again.

This guide covers everything: the mechanism, the evidence, the dosing protocol, the GI problem, and the hydrogel system that solves it.

During maximal effort, your muscles produce energy through anaerobic glycolysis — a fast process that doesn't require oxygen but produces hydrogen ions (H⁺) as a byproduct. As H⁺ accumulates, blood pH drops from its resting value of ~7.4 toward ~6.9 during peak effort.

This acidosis is the burn you feel. It impairs muscle contraction, slows enzyme activity, and forces you to back off. The limiting factor in an 800m race or a 5-minute cycling interval isn't usually your aerobic engine — it's the acid environment shutting it down.

The result: your blood pH stays closer to 7.1–7.2 instead of falling to 6.9 during hard efforts. That difference extends how long you can sustain maximal intensity before acid forces you to slow down.

The evidence-based dose is 0.3g of sodium bicarbonate per kilogram of body weight. Here's what that looks like in practice:

If you're new to bicarb, start at 0.2g/kg and build up over 2–3 sessions. Your gut needs to adapt before you hit the full therapeutic dose.

Here's the catch that stops most athletes: when you dissolve 19g of sodium bicarbonate in water and drink it, it reacts with your stomach acid (HCl) immediately — producing CO₂ gas, causing bloating, nausea, and worse.

The solution is hydrogel encapsulation. By mixing bicarb with maltodextrin, fructose, and xanthan gum — and letting it gel for 3–5 minutes in water — you create a thick matrix that protects the bicarb from stomach acid. The gel passes through the stomach largely intact and releases the bicarb in the small intestine, where it absorbs cleanly into the bloodstream.

This is the mechanism behind Maurten's Bicarb System (retail: ~$17.50/serving). BICARB.NET uses the same principle with the same ingredients — at $5/serving.