By Lachlan Maskell, Co-founder, Fluence | 05/07/2026

Running in Australia is a different sport depending on your postcode and your month. A July tempo run in Hobart asks almost nothing of your hydration. A February long run in Brisbane, Darwin or Cairns, where the humidity means your sweat barely evaporates, can strip litres of fluid and grams of sodium out of you before breakfast. Any guide to electrolytes for runners that ignores that spread is selling you a product, not a plan.

So here is the plan-first version, including the parts where the honest answer is "you don't need anything".

First, the honest baseline

For most runs under about an hour in mild conditions, a normally hydrated runner eating normal meals does not need electrolytes at all. Water before and after, food as usual, done. Sports Dietitians Australia's fluid guidance and the American College of Sports Medicine's position stand both frame electrolyte replacement as something that scales with sweat losses, not a default requirement for all exercise.

Electrolytes earn their place for runners in specific situations:

  • Heat and humidity, which drive sweat rates up dramatically
  • Long runs beyond roughly 60 to 90 minutes
  • Double days and high-mileage weeks, where losses accumulate
  • Salty sweaters, who lose far more sodium per litre than average
  • Early-morning fasted runs, where no meal precedes or immediately follows the session

If your running lives in those brackets even part of the year, and in most of Australia it does from roughly November to March, it is worth building a simple routine.

Know your sweat: testing basics

You do not need a laboratory to get useful numbers, though labs exist if you want precision.

Sweat rate, the towel-and-scales method. Weigh yourself immediately before a run (minimal clothing, after a toilet stop) and immediately after (towel off first). Add the weight of anything you drank during the run. Each kilogram of loss is roughly one litre of sweat. Do this a few times across different temperatures and you will know your personal range. This is the same field method sports dietitians use with athletes.

Sweat sodium, the rough signals. Published research puts sweat sodium anywhere from about 230mg to over 2,000mg per litre between individuals, with around 800mg per litre being typical. White salt crust on your cap and singlet, stinging eyes, and a history of late-run cramping in heat are soft signals you may sit toward the salty end. If you race seriously, a professional sweat sodium test (the kind Precision Hydration and some Australian sports dietitians offer) turns that guess into a number.

A moderate sweater on a one-hour humid run might lose around 1 to 1.5 litres and somewhere near 800 to 1,200mg of sodium. A salty, heavy sweater on the same run could lose double that. Your plan should follow your numbers, not your training partner's.

Before, during, after

Before the run

Start hydrated rather than trying to fix a deficit mid-run. Practical version: drink normally through the day prior, and have roughly 300 to 500mL of fluid in the hour or two before longer or hotter runs. Pale-straw urine is the low-tech check. For an early hot-weather long run, a serve of electrolytes in that pre-run fluid, such as one Base 250 sachet (250mg sodium, 250mg potassium, 60mg magnesium, 40mg vitamin C, zero sugar), gives you a head start on what the session will take out, without sugar you do not need at 5am. Because it is non-carbonated, it sits quietly in the stomach, which matters more before a run than marketing copy admits.

During the run

  • Under 60 minutes, mild conditions: nothing, or water to thirst. Genuinely.
  • 60 to 90+ minutes, or shorter but brutal heat: water plus electrolytes, drinking to thirst as a starting rule. The ACSM guidance emphasises avoiding both significant dehydration and overdrinking; both ends hurt performance, and drinking far beyond thirst carries its own risks.
  • Beyond about 90 minutes: carbohydrate enters the conversation, roughly 30 to 60g per hour per the sports nutrition literature. A zero-sugar electrolyte plus gels or chews, or a carbohydrate sports drink, are both legitimate ways to get there. This is the one context where the sugary bottle is the right tool, and we say that as a zero-sugar brand.

For heavy sweaters doing long hot sessions, this is also where higher-sodium products in the 500 to 1000mg tier, or a doubled serve of a moderate product, make sense. A single 250mg sachet is not designed to fully cover a two-hour Darwin long run for a salty sweater, and we would rather tell you that here than have you find out at the 90-minute mark.

After the run

Post-run is where the moderate tier quietly does its best work. Research on rehydration suggests replacing roughly 125 to 150 per cent of the fluid deficit over the following hours, and that fluid is retained better when it comes with sodium, whether from food or a drink. If you finish a long run and head straight into a normal meal, food handles much of it. If breakfast is still hours away, or you simply do not feel like salty food after a hot session, a sachet in your first big glass of water replaces electrolytes lost through sweat while you get on with the morning. Zero calories, no artificial colours, and it does not fight with your coffee.

One more note for the curious: Base 250's elemental magnesium reacts with water to release dissolved molecular hydrogen, one of the most studied molecules in wellness science. Research suggests molecular hydrogen may support antioxidant capacity, lower perceived exertion and aid recovery - the science is promising but still developing. Runners are a sceptical audience and that is healthy; the full evidence picture is on our science page, and the electrolytes stand on their own regardless.

A simple season-by-season framework for Australian runners

  • Cool months, easy running: water, food, nothing fancy.
  • Cool months, long runs: water during, electrolytes after if the run was long enough to leave you depleted.
  • Hot months, most runs: electrolytes after hot sessions as routine; during, for anything over an hour.
  • Hot and humid (northern Australia, east coast summer): treat every run over 45 to 60 minutes as a sweat event; pre-load fluids for long runs, carry fluid plus electrolytes during, rehydrate deliberately after. Salty sweaters should look at higher-sodium options or double serves for the longest sessions.

Where Base 250 fits, and where it does not

We built Base 250 for the running most Australians actually do: the daily 5 to 10km, the hot commute-adjacent session, the long run recovery, the fasted morning start. It is built for daily use, which is exactly why the sodium is moderate; a runner using it five days a week is not stacking 5,000mg of supplemental sodium onto an Australian diet that already runs high. The 30-Pack is $69.99 ($2.33 per serve), and the Trio 15-Pack at $39.99 lets you test Berry, Lemon and Tropical across a training block before committing.

Where it is not the whole answer: multi-hour hot races and confirmed heavy salty sweaters, who should reach for the 500 to 1000mg tier or scale up serves. Match the tool to the run. That is the entire philosophy, and you can explore the range at our electrolyte hub.

Sources

  • Sawka MN et al. American College of Sports Medicine position stand: exercise and fluid replacement. 2007. https://pubmed.ncbi.nlm.nih.gov/17277604/
  • Baker LB. Sweating rate and sweat sodium concentration in athletes: a review of methodology and intra/interindividual variability. Sports Medicine, 2017. https://pubmed.ncbi.nlm.nih.gov/28332116/
  • McDermott BP et al. National Athletic Trainers' Association position statement: fluid replacement for the physically active. Journal of Athletic Training, 2017. https://pubmed.ncbi.nlm.nih.gov/28985128/
  • Sports Dietitians Australia, Fluids in Sport fact sheet. https://www.sportsdietitians.com.au/factsheets/fuelling-recovery/fluids-in-sport/
  • Jeukendrup A. A step towards personalized sports nutrition: carbohydrate intake during exercise. Sports Medicine, 2014. https://pubmed.ncbi.nlm.nih.gov/24791914/
  • Ohsawa I et al. Hydrogen acts as a therapeutic antioxidant by selectively reducing cytotoxic oxygen radicals. Nature Medicine, 2007. https://pubmed.ncbi.nlm.nih.gov/17486089/

This article is general information only and is not medical advice. If you have a medical condition, are pregnant or breastfeeding, or take prescribed medication, talk to your doctor or pharmacist before changing your hydration or supplement routine.