You sweat like an athlete. Hydrate like one.
A hot class feels like rest, so people replace their fluids like they've been at a desk. But at 105–107°F for 60–90 minutes, your losses look like an endurance race — you just did it lying on a mat. Here's what you actually lose, and what to put back.
Get your exact number, free →The losses are hidden in plain sweat.
Because hot yoga is calm and low-impact, the sweat rate surprises people. A 73-minute class in a 107°F room runs a sweat rate near 1.7 liters an hour — squarely in endurance-athlete territory:
A standard sports drink puts back roughly 7% of the sodium in that. The rest is the afternoon headache, the 3 a.m. calf cramp, the wiped-out feeling that gets blamed on everything but salt. The physiology behind it →
Find your hot-yoga formula.
Not a flavor — a dose, sized to how you actually sweat and how often you practice. Tap the one that sounds like you; the calculator loads it, and you can adjust anything from there.
The Daily Yogi
You practice most days. Moderate loss per class, but relentless across the week — the steady daily replacement.
The Heavy Sweater
Salt-crust on your skin, soaked by minute 20 — the formula every store-bought tab under-doses. A salty sweater in a hot room.
The Weekend Flow
Fewer but longer sessions. A bigger single-class loss, so the per-class replacement matters more — a long, steady flow.
New to the Heat
Newer to hot yoga, a shorter or cooler class, a lighter sweater. Start here and dial it up as you acclimate.
Each formula is a starting point from the same model behind the calculator — weigh in and out once for your exact number. Prefer to build a month at a time? The Jar Kit →
Why “just drink water” can backfire.
The instinct after a sweaty class is to chug water. But water without sodium dilutes the sodium already in your blood — and your brain's salt sensor (the OVLT) reads that dilution and, in the extreme, over-drinking plain water causes hyponatremia. You feel it as more thirst, a lingering headache, and no real recovery. The fix isn't less water; it's water with the salt you actually sweated out, so what you drink is absorbed instead of just passing through.
Your number, then the simple protocol.
Start with the free calculator — pick Yoga, your class length and the heat, or weigh in and out for an exact figure. Then this is the rhythm most hot-yoga practitioners settle into:
Make it a habit, not a chore.
Mixing before every class is friction, and friction is why people quit. Two ways to remove it:
The Jar Kit
A month's blend in a jar at your ratio, a calibrated scoop, and a waterproof card printed with your formula. Scoop it, don't measure it.
The Sweat Station
Teach or own a studio? Host a scale + QR so members get their number after class. Zero inventory, a live report, a revenue share.
Your mat isn't the average.
Get the number that's actually yours — free, 60 seconds, no account.
Keep reading
Make your own, dosed to you
The full homemade method, plus how LMNT, Liquid I.V., Nuun and Gatorade compare milligram by milligram.
Why salt, not just water
The OVLT salt sensor, SGLT1 absorption, and the sodium-potassium ratio — primary sources, plain language.
What it actually misses
Pick what you sip now and see the exact gap for a hot class — and the pennies that close it.