Looking into the Potential Strength Benefits of Sodium
Salt has been called the “secret weapon in the gym” and “the newest workout supplement1.” The white granules known as table salt (also sea, kosher, or Himalayan salt) in your kitchen are simply sodium and chloride put together. By itself, sodium is one of several critical electrolytes which are minerals that affect the body’s fluid balance, muscle and nerve impulses, blood pressure and acid–base balance.
Though human requirements are only 300-500 milligrams of sodium daily, the average American consumes ten times that – over 3,400 mg2! It’s well known that athletes have a higher need for sodium, mainly due to sweat losses. However, competitive athletes also train hours a day (and the majority not resistance work) compared to the average person in the weight room. So then, we wondered where the hype about extra sodium came from. Does liberally salting nearly everything you put in your mouth help you pump more iron in the gym?
The Strength Training Community
Reading through three online sources3,4,5 touting the benefits of salt for size and strength it would appear that we’ve missed out on the key to bodybuilding success! Sodium increases blood volume and intracellular water retention. True, but sodium just doing its job for fluid status and muscle contraction doesn’t mean more salt enhances power and strength for greater gains. None of those articles provide evidence-based references or citations to support these supposed enhancements. (Sodium phosphate is a different molecule that is mentioned as an intracellular buffer that can increase aerobic and anaerobic performance when supplemented3.) The authors do agree that although you shouldn’t limit sodium, you don’t need supplemental salt for strength gains, just ample dietary consumption. A fourth bodybuilding source6 advises not to add excessive sodium to meals and shares that it’s more important to have potassium in balance with sodium intake.
Sports Nutrition Experts
We asked Jennifer McDaniel, RDN, a Certified Specialist in Sports Dietetics (CSSD), in the St. Louis, Missouri area if strength athletes and power lifters need additional sodium beyond that in the typical American diet. She informed us that sodium requirements vary significantly based on intensity and time of training session, sweat rate and acclimation to the training environment. “Based on the current research available, strength-based athletes do not need more than the average intake of sodium from the typical Western diet,” McDaniel said. She explained that most athletes’ eating habits far exceed the recommended limit of 2,300 mg sodium* per day making it unlikely that strength trained athletes would need an increase in daily sodium for the average hour–long training bout.
* for the general public, from the 2015-2020 US Dietary Guidelines7.
Also, nationally known, Marie Spano, RD, CSSD and Certified Strength and Conditioning Specialist®, gave us her input regarding athletes’ sodium needs. She shared that dehydration can decrease strength and power. “Your muscles need sodium to hold on to more fluid and for muscular contractions, so consume adequate sodium to cover sodium losses through sweat,” Spano advises. She previously wrote, “To achieve proper hydration, athletes may want to add sodium to their sports drinks or preworkout meals to help retain the fluid they’re consuming.8” The amount depends on total dietary sodium intake and sodium losses through sweat while training in a particular environment.
American College of Sports Medicine’s (ACSM) 2016 position stand and The International Society of Sport Nutrition’s (ISSN) 2018 research and recommendation update both addressed sodium. Regarding hydration, the ACSM indicated, “Sodium consumed in pre-exercise fluids and foods may help with fluid retention,” and advised ingesting sodium during exercise when large sweat losses occur9. The ISSN stated that inadequate sodium would impair performance and advised replacing adequate amounts due to sweat losses10. In regard to extra sodium the Society indicated it was beneficial for hydration in the early days of training in the heat10.
Neither ACSM or ISSN directly mentioned sodium involved in strength, power, weight training or muscle mass. In fact, the ISSN didn’t list any sodium compounds as “muscle building supplements” based on available literature but did name sodium bicarbonate and sodium phosphate under the “performance enhancement” category, noting there was strong evidence to support their efficacy10. The Society also indicated limited or mixed evidence to support the efficacy of [sodium] nitrates to improve aerobic work performance and endurance exercise10.
Evidence from Scientific Research
Being that salt is everywhere in our diet, research on supplemental sodium chloride solely for muscle strength or growth is lacking. Sodium bicarbonate, on the other hand, is not easily obtained from food and has evidence as a modestly effective sports nutrition supplement for short-term, high intensity exercise (anaerobic work) performance11,12. Benefits are most likely due to its action as an extracellular (blood) buffer11. Sodium citrate is a potential alternative buffer, but with unknown effectiveness. For endurance work, sodium phosphate may enhance performance12.
The Final Word
So, it seems the hype surrounding salt for strength comes from the importance of sodium for hydration and muscular contraction. Most people generally get enough of it in the form of sodium chloride, more of which doesn’t help strength gains as long as dehydration is prevented, particularly for training sessions that are very long or in the heat. Other sodium molecules consumed as sports nutrition supplements may offer ergogenic effects that can’t be derived from table salt, namely sodium bicarbonate for anaerobic work. The consensus is not to limit salt if you’re intensely resistance training, but you don’t need to intentionally use the saltshaker everywhere either. Consider just drinking a higher sodium fluid electrolyte beverage pre-workout.