Do You Actually Need Electrolytes? What Brighton Runners and Gym-Goers Need to Know
Walk into any health food shop in Brighton and you'll be confronted by a wall of pastel-coloured pouches, all promising "scientifically optimised electrolyte ratios" for peak hydration. The marketing is clever. The science behind most of it? Less so.
Here's the honest answer.
Most People Don't Need Electrolytes
Under normal conditions — a regular day, a standard gym session, your morning run along the seafront — most people do not need electrolyte supplementation. Your diet, assuming it's reasonably balanced, covers your bases.
The threshold where electrolytes genuinely start to earn their place is sustained, fairly intense endurance exercise lasting 75 to 90 minutes or more. That's it. That's the bar. Not your lunchtime walk. Not a spin class. Not commuting.
The supplements industry would very much like you to forget this.
But a Heatwave Changes the Rules
Here's where it gets more nuanced — and more relevant right now.
When temperatures rise and you're sweating continuously throughout the day just going about normal life, the equation shifts. If you're losing fluid consistently for more than two hours — before you've even factored in a training session — then electrolyte replacement becomes genuinely useful, not just a marketing gimmick.
Add a workout on top of ambient heat-driven sweating, and electrolytes move from "optional" to "good idea."
What to Actually Buy (And What to Ignore)
You do not need a monthly subscription. You do not need the most expensive product on the shelf. Head to your local pharmacy — Boots on Western Road, or any independent chemist in Hove — or shop online, and look for the most affordable electrolyte powder that hits these numbers per serving:
The essentials:
Sodium — 500–700mg
Chloride — 400–600mg
Bonus if present:
Potassium — 200–400mg
Magnesium — 100–200mg
Sodium and chloride are your workhorses — the minerals you're actually losing through sweat. Potassium and magnesium support muscle function and recovery and are worth having, but they're secondary.
Use it while the heat lasts and you're sweating through the day. When things cool down and you stop sweating at rest, you can stop.
The Bottom Line
Electrolytes have a real role in certain conditions. A summer heatwave in Brighton is one of them. A Tuesday morning at your desk is not.
Evidence first. No subscription required.
Duncan is a physiotherapist and longevity specialist at Life is Movement clinic in Brighton and Hove. For movement assessments, injury rehab, and evidence-based performance advice, visit lifeismovementclinic.com.
