Pick an electrolyte powder by sodium per hour, not by brand
In short
The ACSM benchmark for sodium replacement is roughly 500mg per hour, while dietitian-reviewed electrolyte powders deliver anywhere from 300mg to 1,000mg of sodium per serving — a threefold spread. For a lifter training 60 to 90 minutes in an air-conditioned gym, a 300–500mg serving already meets that benchmark; 1,000mg formulas are built for long endurance efforts with heavy sweat loss. The three things worth checking on the label are sodium in mg, added sugar in grams, and whether the product is third-party tested.
There is one number that actually separates electrolyte powders: sodium per serving. Across dietitian-reviewed products it lands at 300mg, 330mg, 500mg and 1,000mg — and every one of those tubs says the same word, "electrolytes", on the front. A threefold difference hides behind identical labelling.
The reference point is the ACSM guideline of roughly 500mg of sodium per hour. When a product claims it "meets ACSM recommendations", that is the figure being met, and the 500mg formulas are built to it.
How much sodium do you actually need?
Session length and sweat rate decide it. Products designed around workouts of an hour or less sit near 300mg per serving, which covers most lifters running the big three plus accessories in an air-conditioned room. At the other end, 1,000mg formulas assume a 10-mile run or a long sweaty ride — they taste genuinely salty, which is why the instructions say to mix one packet into 16 to 32 ounces (470–950ml) of water. Use less water and the salt comes through harder.
What else is in there?
Potassium and magnesium are lost in sweat too, but in far smaller amounts than sodium, and the formulas mirror that ratio — a 1,000mg sodium product carries around 200mg potassium and 60mg magnesium. One popular 500mg formula pairs it with 370mg of potassium and no magnesium or calcium at all, so if you assumed a full four-electrolyte blend, read the panel. Some products add zinc at 15% of the daily value, a trace mineral that helps the intestines absorb water and electrolytes.
How much sugar is in it?
Added sugar spans 0g to 11g per serving. Older formulas carry 11g of added sugar; newer sugar-free lines switch to stevia or allulose and drop to 1–2g of carbohydrate. A middle option sits at 7g added sugar and 9g total carbohydrate. The industry moved away from carbohydrate blends specifically so athletes can dial carbohydrate intake separately — which is the right direction for lifters. Intra-session carbs belong in your meal and supplement plan, not smuggled into a hydration drink.
These figures come from a dietitian product review, not a randomised trial. Sodium loading is a different decision if you have high blood pressure or kidney disease — ask a doctor. Products sweetened with allulose can cause mild bloating or gas in some people. For how to read supplement labels generally, see choosing creatine monohydrate and salmonella in greens powder.
Three lines on the label
Start with third-party testing — it is the only mechanism confirming that what the panel lists is what is in the tub. If you compete, look further for Informed Sport certification, which means the product has been screened for substances banned by the major athletic bodies. Sodium in mg comes second, added sugar third.
You can measure your own requirement. The difference between your weight immediately before and after a session is mostly sweat, and the bigger that drop, the higher up the range you should shop. But do not log that number. A Muscle Index score takes bodyweight as an input, so a score computed from post-sweat weight reads higher than it should. Sweat-loss weight and index weight are two different numbers, and index weight should be taken under the same conditions each time, away from training.
Diet context matters more than the marketing does. If your meals already run high in sodium, the 1,000mg in a packet is added on top of that, not a replacement for it. If the goal is replacing what you lost during a session, start in the 300–500mg band and only move up for genuinely sweaty summer training.
Frequently asked questions
How much sodium should an electrolyte powder have?
The ACSM benchmark for sodium replacement is roughly 500mg per hour. Commercial powders range from 300mg to 1,000mg per serving, and for a gym session of around an hour indoors, the 300–500mg band already meets that benchmark.
Who are the 1,000mg formulas for?
They are built for high-sweat endurance work — a 10-mile run or a long sweaty ride. The salt is strong enough that the maker recommends mixing one packet into 16 to 32 ounces of water, and it is more than an hour of air-conditioned lifting requires.
Do potassium and magnesium matter?
Both are lost in sweat but in far smaller amounts than sodium, and the formulas reflect that — around 200mg potassium and 60mg magnesium alongside 1,000mg of sodium. Some products omit magnesium and calcium entirely, so check the panel rather than assuming a full blend.
Is sugar-free better?
For lifters, usually. Added sugar ranges from 11g per serving down to 1–2g of carbohydrate in sugar-free lines, and removing the carbohydrate lets you control intake from food instead. Note that allulose-sweetened products can cause mild bloating in some people.
What should you check first on the label?
Third-party testing, then sodium in mg, then added sugar. Third-party testing is what confirms the panel is accurate, and competing athletes should also look for Informed Sport certification, meaning the product was screened for banned substances.
Source: Men's Health