The bicarbonate buffer system plays a critical role in regulating blood pH and dealing with the buildup of hydrogen ions during intense exercise. Unsurprisingly, sodium bicarbonate (also known as baking soda) has been a reasonably popular supplementation strategy for people doing high-intensity exercise, particularly for repeated sprint tasks or steady-state bouts lasting from 30 seconds to a couple minutes in duration.
A recent meta-analysis sought to determine if sodium bicarbonate supplementation might benefit strength or muscular endurance outcomes. 13 studies looked at muscular endurance; some assessed the endurance capacity of small muscle groups, and others looked at large muscle groups. 11 studies assessed some form of muscular strength, with some tests occurring in a rested state and others occurring in a fatigued state.
Results indicated that sodium bicarbonate supplementation enhanced muscular endurance, whether the task relied on small or large muscle groups. However, strength was not significantly improved, whether the task was completed in a rested or fatigued state. Based on its mechanism of action, this makes sense; theoretically, it should help delay fatigue in tasks that challenge the anaerobic energy system.
The bottom line: Sodium bicarbonate might help you crank out a few more reps if you’re training with high reps or short rest periods between sets, but it’s probably not going to acutely help you lift larger absolute loads.
It’s important to note that sodium bicarbonate generally has a pretty tight window for dosing – too small of a dose is ineffective, but too large of a dose often leads to gastrointestinal discomfort and diarrhea. So, if you’re thinking about experimenting with sodium bicarbonate supplementation, make sure it actually makes sense for the type of training you do, and keep a close eye on your dosing strategy. You might also consider implementing some creative strategies for supplement timing (as seen here) in order to increase bicarbonate levels without causing GI discomfort.