Electrolytes for Workouts: When You Need Them and How Much
Electrolyte drinks, powders and tablets are everywhere now, and the marketing makes it sound like plain water is no longer enough. For some sessions, that is true. For plenty of others, it is not. Knowing when electrolytes for workouts actually help comes down to how long you train, how hot it is, and how much you personally sweat.
Here is what the American College of Sports Medicine and a large dataset of more than 1,300 athletes show about sweat losses, how to estimate your own needs, and where sodium, potassium and magnesium fit in.
Key Takeaways
- The ACSM recommends drinking during exercise to avoid losing more than 2% of body weight from water deficit.
- Sweat rates and sweat sodium vary widely between people, so personalized plans beat one-size-fits-all rules.
- In data from 1,303 athletes, average sweat rates ranged from about 0.8 to 1.5 liters per hour depending on the sport.
- Sodium is the electrolyte sweat research tracks most closely; long, hot or very sweaty sessions are where added electrolytes make the most sense.
- Weighing yourself before and after training is the simplest way to estimate your own sweat losses.
What Electrolytes Do During Exercise
Electrolytes are minerals that carry an electrical charge when dissolved in body fluids. Sodium, potassium, magnesium, calcium and chloride help regulate fluid balance, nerve signaling and muscle contraction. When you sweat to cool down, you lose water along with some of these minerals.
Sodium gets most of the attention because it is the electrolyte researchers focus on in sweat testing. A 2017 review in Sports Medicine by Lindsay Baker centers on sweating rate and sweat sodium concentration and stresses that both can vary considerably within and among individuals. Factors include exercise intensity, environmental conditions, heat acclimation, aerobic capacity, body size and composition, protective equipment, sex, maturation, aging, diet and hydration status.
What the ACSM Recommends
The American College of Sports Medicine's position stand on exercise and fluid replacement remains a widely cited reference. Its core guidance is practical:
- Before: start training well hydrated with normal electrolyte levels. When needed, drink fluids at least several hours before activity so your body can absorb them and urine output can return to normal.
- During: drink to avoid excessive dehydration, defined as more than 2% body weight loss from water deficit, and excessive shifts in electrolyte balance that can hurt performance.
- Electrolytes: beverages containing electrolytes and carbohydrates can provide benefits over water alone under certain circumstances.
- After: replace any remaining fluid and electrolyte deficit. How fast you need to do it depends on when you train next and how big the deficit is.
Because sweat rates and sweat electrolyte content vary so much, the ACSM recommends customized fluid replacement plans rather than fixed drinking schedules. The goal is not to drink as much as possible. It is to roughly match what you lose.
2%
Body weight loss to stay under
1,303
Athletes in the sweat dataset
1.5 L/h
Avg sweat rate, American football
How Much Sodium Do Athletes Lose in Sweat?
A 2019 study in the Journal of Sports Sciences by Barnes and colleagues compiled sweat testing data from 1,303 athletes collected between 2000 and 2017. Sweat rate was measured from body mass change during exercise, and sweat sodium was measured with a standardized absorbent patch method. Note on funding: the authors are from the Gatorade Sports Science Institute, and the study was funded by PepsiCo, which sells sports drinks.
The averages differed significantly by sport. We converted the published sodium values from millimoles to milligrams (1 mmol of sodium is about 23 mg) and rounded them:
| Sport | Avg sweat rate | Avg sweat sodium loss |
|---|---|---|
| American football | 1.51 L/h | 55.9 mmol/h (about 1,290 mg/h) |
| Endurance | 1.28 L/h | 51.7 mmol/h (about 1,190 mg/h) |
| Basketball | 0.95 L/h | 34.5 mmol/h (about 790 mg/h) |
| Soccer | 0.94 L/h | 34.6 mmol/h (about 800 mg/h) |
| Baseball | 0.83 L/h | 27.2 mmol/h (about 630 mg/h) |
Values are group averages per hour of exercise from Barnes et al. (2019). Individual athletes varied widely around these numbers.
The authors concluded that American football and endurance athletes have the greatest need for deliberate hydration strategies. Notice the spread, too: these are averages, and individual standard deviations were large. Two people doing the same workout can lose very different amounts.
When You Need Electrolytes for Workouts
You probably benefit most if
- You train for longer than about an hour, especially continuous endurance work.
- You train in heat or humidity, or wear heavy gear.
- You are a heavy sweater or know you lose a lot of sodium in sweat.
- You train twice in one day and need to rehydrate quickly between sessions.
Water and food may be enough if
You do a typical 45- to 60-minute lifting session in a climate-controlled gym and eat regular meals. Food supplies sodium, potassium and magnesium, and the next meal usually covers modest sweat losses. That is consistent with the ACSM framing that electrolyte drinks help "under certain circumstances," not always.
Do not forget potassium and magnesium
Daily intake matters more than what you sip mid-workout. According to the NIH Office of Dietary Supplements, the adequate intake for potassium is 3,400 mg per day for adult men and 2,600 mg for adult women. The recommended dietary allowance for magnesium is 400 to 420 mg per day for adult men and 310 to 320 mg for adult women, depending on age. Fruits, vegetables, beans, nuts, seeds and dairy are the foundation.
How to Estimate Your Own Sweat Rate
The ACSM notes that individual sweat rates can be estimated by measuring body weight before and after exercise, and the Baker review calls body mass change the simplest and most accurate way to measure whole-body sweat rate. Here is a simple version:
- Weigh yourself nude or in minimal clothing right before a typical session.
- Track how much fluid you drink during the session.
- Towel off and weigh yourself again right after, before eating, drinking more or using the bathroom.
- Weight lost plus fluid consumed is roughly your sweat loss. One kilogram is about one liter; one pound is roughly 15 to 16 fluid ounces.
If you regularly lose close to 2% of your body weight, drink more during sessions. Repeat the test in different conditions, because summer and winter numbers can be very different. If you also take glycerol for hydration, see our article on glycerol supplement benefits.
Where goBHB® Fits In
Most electrolyte products are minerals with flavoring. goBHB® takes a different approach: it is a ketone supplement first, made with patented beta-hydroxybutyrate (BHB) salts. Because that BHB is bound to calcium, magnesium, sodium and potassium, each serving also brings electrolyte minerals along with it. CleanForm designed it to provide electrolyte support and to support hydration and muscle function, with no caffeine.* Check the supplement facts panel for the mineral amounts per scoop.
It is not a full sweat-replacement drink for a three-hour run in August. For long, hot sessions, you will still want enough fluid and sodium from food or a dedicated sports drink. But if you want a caffeine-free scoop that adds ketones and some minerals to your training water, goBHB is an easy fit. Choose Unflavored to mix into water, coffee or your pre-workout, or Strawberry Kiwi or Tangy Apple, which are naturally flavored, sweetened with stevia and 20 calories per scoop. Each tub has 30 servings. For what the research says about BHB salts themselves, read do exogenous ketones work?
Safety note: goBHB contains mineral salts. If you have kidney disease, have been told to limit sodium or potassium, take medications that affect electrolytes, or are pregnant or nursing, talk to your healthcare provider before using it.
Ketones Plus Minerals
goBHB®
- Patented BHB salts of calcium, magnesium, sodium and potassium
- Zero caffeine, 50/50 DL blend, 30 servings per tub
- Unflavored, Strawberry Kiwi or Tangy Apple
Electrolytes FAQ
Should I drink electrolytes before or after a workout?
It depends on the session. The ACSM suggests starting well hydrated, drinking during exercise to stay under 2% body weight loss, and replacing any remaining fluid and electrolyte deficit afterward. For short sessions, a normal meal afterward often covers it.
Do I need electrolytes if I lift weights?
For most indoor lifting sessions under an hour, water plus regular meals is usually enough. Long sessions, hot gyms, two-a-days or very heavy sweating are when electrolytes become more useful.
How do I know if I am a salty sweater?
Some people notice white residue on clothing after training, but that is not a reliable measure. Lab sweat testing is more precise, though results depend heavily on how the test is done.
Can you drink too many electrolytes?
Yes. More is not better. Aim to roughly replace what you lose, stay within daily nutrient guidelines, and talk to your doctor if you have kidney issues or have been told to limit sodium or potassium.
The Bottom Line
Electrolytes for workouts are most useful when sessions are long, hot or very sweaty, and sweat losses vary so much between people that a quick before-and-after weigh-in is worth more than any generic rule. Aim to stay under 2% body weight loss, replace sodium when you sweat heavily, and build potassium and magnesium through your daily diet. If you want a caffeine-free option, goBHB is a simple way to add ketones and electrolyte minerals to your training water.
Sources: American College of Sports Medicine; Sawka MN, et al. American College of Sports Medicine position stand. Exercise and fluid replacement. Med Sci Sports Exerc. 2007;39(2):377-390. Barnes KA, et al. Normative data for sweating rate, sweat sodium concentration, and sweat sodium loss in athletes: an update and analysis by sport. J Sports Sci. 2019;37(20):2356-2366. Baker LB. Sweating rate and sweat sodium concentration in athletes: a review of methodology and intra/interindividual variability. Sports Med. 2017;47(Suppl 1):111-128. NIH Office of Dietary Supplements. Potassium fact sheet and Magnesium fact sheet.
*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. Consult your healthcare provider before starting any supplement.