By Monica N. for Stacked Fitness Hydration
SEPTEMBER 2, 2026 • 8 MIN READ
Key Takeaways
- Sweat sodium concentration ranges from roughly 200 mg/L for light sweaters to over 2,300 mg/L for salty sweaters, with the average athlete losing around 950 mg/L, so generic hydration advice misses most people.
- Potassium is the more commonly under-consumed electrolyte: the average adult man takes in only about 88.7% of the NIH's daily target, a deficit that exists before a single drop of sweat is lost.
- Creatine supplementation increases total body water by roughly 6%, mostly stored inside muscle cells, which raises, not lowers, the practical need for consistent electrolyte intake.
- Stacked Fitness Hydration's TONE pairs 5g of creatine with 980mg of electrolytes in a single daily stick, so the extra fluid demand creatine creates is met with the sodium and potassium to actually hold onto it.
Most active adults treat hydration as a water problem. Carry a bottle, drink on schedule, call it handled. But water is only half of what you actually lose in a hard training session, and the other half, sodium and potassium, is the part almost nobody tracks until a workout falls apart for no obvious reason.
Electrolytes are not a bonus category bolted onto hydration. They are the minerals that let your body hold onto the fluid you are drinking, fire your muscles correctly, and avoid the mid session crash that usually gets blamed on "not eating enough" when it is really a sodium and potassium problem. Here is what the current research says about how much active adults actually lose, what a real shortfall looks like, and where electrolytes intersect with creatine in a daily routine.
Water gets the credit, electrolytes do the work
Sodium is the primary electrolyte lost in sweat, and it is doing more than seasoning your fluids. It regulates the balance of fluid between the inside and outside of your cells, supports nerve signaling, and helps your muscles contract the way they are supposed to during a heavy set or a long run. The American College of Sports Medicine has treated sodium as a core part of the hydration equation for decades in its position stand on exercise and fluid replacement, not as an optional add on, because water without enough sodium alongside it is processed and cleared by the body differently than water paired with electrolytes.
Potassium works alongside sodium on the other side of that same fluid balance system, and it gets far less attention even though shortfalls in it are arguably more common among active adults, for reasons the numbers below make clear.
How much sodium you actually lose when you train
Sweat sodium concentration varies enormously between people, mostly due to genetics and how efficiently your sweat glands reabsorb sodium before it reaches the skin. Sweat testing data compiled by Precision Hydration puts the range at roughly 200 milligrams of sodium per liter of sweat on the low end, to more than 2,300 milligrams per liter for so called "salty sweaters," with the average athlete landing somewhere around 950 mg per liter.
How much of that concentration you actually lose in an hour depends on both that number and how much you sweat, which is itself highly dependent on sport and intensity. A normative dataset from the Gatorade Sports Science Institute, drawn from more than 1,300 athletes, found sweat sodium loss rates that scale directly with training demand, from roughly 27 mmol per hour in baseball up to nearly 56 mmol per hour in football and endurance work. Converted to milligrams, that is the difference between about 626 mg lost per hour of baseball and more than 1,280 mg lost per hour of football or hard endurance training.
For context, the FDA's daily value for sodium tops out at 2,300 milligrams, about a teaspoon of table salt, the same ceiling most nutrition labels are built around. A single hour of endurance training can burn through roughly half of that ceiling in sweat losses alone, and a hard hour of football conditioning can burn through more, which is a very different picture than the "just cut back on salt" advice most adults are used to hearing.
Potassium: the electrolyte most active adults are quietly short on
Sodium gets most of the hydration conversation, but potassium is arguably the more commonly under consumed electrolyte among active adults, and it does not get replaced by a pinch of salt. The NIH's Office of Dietary Supplements sets an adequate intake of 3,400 milligrams a day for adult men and 2,600 milligrams for adult women. Actual intake, based on NHANES survey data cited in that same fact sheet, averages roughly 3,016 milligrams for men and 2,320 milligrams for women, which means most people are training on a baseline deficit before a single drop of sweat is ever lost.
That gap matters because potassium works on the other side of the same fluid balance system sodium operates in, and low levels (a condition called hypokalemia when it becomes clinically significant) show up first as constipation, fatigue, muscle weakness, and general malaise, according to the same NIH fact sheet, exactly the symptoms that get written off as "just an off day" instead of a mineral gap.
The warning signs are easy to miss
Most active adults are not dealing with a medical electrolyte emergency day to day, but the milder end of the spectrum, cramping, unusual fatigue mid session, headaches after a long sweaty workout, is common and usually gets misread as under eating or overtraining. At the far, more serious end of the spectrum, a position stand from the International Society of Sports Nutrition on ultra endurance exercise notes that exercise associated hyponatremia, a drop in blood sodium that can become dangerous, is driven by two things: heavy sodium loss through sweat during long efforts in heat, and aggressive fluid intake using low electrolyte drinks that dilutes the sodium you have left. The same position stand recommends athletes target roughly 500 to 700 milligrams of sodium per liter of fluid during long sessions, rising toward 300 to 600 mg per hour in hot, humid conditions, well above what most sports drinks actually contain.
Why electrolytes and creatine work better stacked together
Creatine adds another layer to this picture that most people never connect back to electrolytes. A controlled study published in the Journal of Athletic Training found that creatine supplementation increased total body water by roughly 6 percent over about four weeks of use, with that extra fluid stored primarily inside muscle cells rather than under the skin. That is a feature, not a side effect, for anyone chasing muscle fullness and training capacity, but it also means creatine users are asking their body to hold onto meaningfully more fluid than usual, which raises the practical need for consistent electrolyte intake rather than lowering it.
This is exactly the gap Stacked's TONE was built around. Instead of managing a separate hydration supplement and a separate tub of creatine, TONE combines 5 grams of creatine with 980 milligrams of electrolytes in one daily stick, so the extra fluid demand creatine creates is met with the sodium and potassium to actually hold onto it. If you are comparing hydration supplements or looking for the best creatine and hydration product that treats electrolytes in creatine as one problem instead of two, that is the thinking behind the formula.
A practical electrolyte routine you can actually follow
You do not need to weigh your sweat or memorize milligram targets to get most of the benefit here. A few practical starting points:
Do not wait for thirst. Thirst tends to lag behind an actual sodium and potassium deficit, especially once you are training regularly, so build electrolyte intake into training days by default rather than reacting to how you feel mid session.
Match intake to training load, not a flat number. An easy 30 minute walk and a hard 90 minute endurance session are not the same electrolyte event, even though both technically count as "exercise."
Cover potassium on purpose. Sodium is easy to over correct for since it is already in most diets; potassium rich foods like bananas, potatoes, and leafy greens need more deliberate attention, especially if you are already tracking sodium closely.
Pair electrolytes with creatine, not around it. If creatine is already part of your routine, a combined hydration in creatine formula removes one more thing to manage on busy training days.
Electrolytes are not a niche concern for ultra endurance athletes alone. They are the difference between a hydration routine that actually works and one that just moves water through your system without doing much for how you feel or perform.
For more on this, see how much sodium you actually lose in a workout and what athletes get wrong about sodium.
Further reading
American College of Sports Medicine, Position Stand: Exercise and Fluid Replacement
Precision Hydration, How to Estimate Your Sweat Salt Loss
Gatorade Sports Science Institute, Normative Data for Sweating Rate, Sweat Sodium Concentration, and Sweat Sodium Loss in Athletes
NIH Office of Dietary Supplements, Potassium Fact Sheet for Health Professionals
FDA, Sodium in Your Diet
International Society of Sports Nutrition, Position Stand on Ultra Endurance Exercise
Powers et al., Creatine Supplementation Increases Total Body Water Without Altering Fluid Distribution, Journal of Athletic Training, 2003
