The science
The Science: Hydration
Is More Than Water.
Water alone can’t fix dehydration. Here’s what your body actually loses when you work — and how the right electrolytes put it back.
Sweat drains fluid and five electrolytes — sodium, potassium, magnesium, calcium, and chloride — that carry the electrical charge your muscles and nerves run on. Plain water only dilutes what’s left; Redi replaces all five in absorbable forms.
Why water isn’t enough
Through a long shift or a hard day, you don’t just lose fluid — you lose electrolytes: sodium, potassium, magnesium, calcium, and chloride. These minerals carry the electrical charge that lets your muscles contract, your nerves fire, and your brain stay sharp. Drink plain water to replace the fluid and you dilute what’s left, which is why you can drink all day and still feel drained, cramped, and foggy. Real rehydration means replacing the water and the minerals together, in a ratio your body can use.
What each electrolyte does
- Sodium — the primary driver of fluid balance. It’s what lets your body hold on to the water you drink instead of passing it straight through. It’s also the electrolyte you lose the most of in sweat.
- Potassium — works with sodium to move fluid into cells and keep your heartbeat and muscles steady. Low potassium is a common cause of the cramps that show up late in a long day.
- Magnesium — supports muscle recovery, energy production, and nerve function through a long day.
- Calcium — essential for muscle contraction and nerve signaling; your muscles literally can’t fire properly without it.
- Chloride — partners with sodium to maintain fluid balance and healthy pH.
Absorption is the whole game
The form of a mineral decides how much of it your body can actually use. Redi uses pink Himalayan sea salt, dimagnesium malate, and calcium citrate — forms chosen for absorption and gentleness on the stomach — instead of the cheapest bulk salts. A label can promise a mineral, but the form is what determines whether that mineral reaches your cells or passes through. Five essential electrolytes, in four premium forms, in every stick pack.
Why physical work changes the math
Most hydration advice is written for someone sitting at a desk or running a race. Neither describes a twelve-hour nursing shift, a day framing a roof in July, or a parent who hasn’t sat down since 6 a.m. Sustained physical work in the heat can cost you a liter of sweat an hour, and with it a heavy dose of sodium — far more than a few sips of water can offset. The longer and hotter the day, the more the balance tips, and the more it matters that what you drink puts back all five electrolytes, not just fluid. That’s the gap Redi is built for.
When to reach for which
Drink Replenish before, during, or after work or exercise — or any time you need hydration, including before bed, since it’s caffeine-free. Reach for Amplify 15–20 minutes before you need energy and focus: it adds caffeine, Alpha-GPC, and NMN to the same hydration base. Both use identical five-electrolyte chemistry; the only question is whether you also want the energy layer.
The bottom line
Hydration isn’t a marketing category — it’s chemistry your body runs on every minute you’re working. Give it water alone and you solve half the problem. Give it water plus the five electrolytes it lost, in forms it can absorb, and you stay steady, clear, and cramp-free through the part of the day that used to break you.
Signs you’re running an electrolyte deficit
Your body is usually telling you before you consciously notice. The common signals during and after hard physical work include muscle cramps and twitches, a dull headache, unusual fatigue or heavy legs, dizziness when you stand, and difficulty concentrating even though you’ve been drinking water. Any one of these can have other causes, but together, on a hot or long working day, they often point to fluid and electrolytes you haven’t replaced.
The useful takeaway isn’t to diagnose yourself mid-shift — it’s to stay ahead of the deficit so you never get there. Hydrating with all five electrolytes steadily, before symptoms show up, is far more effective than trying to rescue yourself once the cramps and fog have already set in. Prevention is a stick pack and a water bottle; the cure is a miserable afternoon.
What is electrolyte imbalance?
An electrolyte imbalance is when the levels of essential minerals in your body — sodium, potassium, magnesium, calcium, and chloride — drift too high or, far more often for active people, too low. Heavy sweating through a long shift, a hot day of physical work, or hard exercise is one of the most common everyday causes, because you lose those minerals in sweat faster than a normal diet and plain water replace them.
The signs of a mild electrolyte imbalance are easy to write off as “just a hard day”: muscle cramps and twitches, fatigue and heavy legs, headaches, dizziness when you stand, an irregular or pounding heartbeat, and trouble concentrating even though you’ve been drinking water. That last part is the giveaway — when water alone isn’t fixing how you feel, it’s usually because the minerals, not just the fluid, are what you’re missing. Replacing all five electrolytes together is how you address and, better yet, stay ahead of the everyday imbalances that come with hard physical work.
To be clear about the line: a severe electrolyte imbalance is a genuine medical condition that can be caused by illness, kidney problems, or medications, and it needs a doctor — not a drink mix. Redi is made for the everyday, exertion-driven losses that come from working hard and sweating, not for treating a medical condition. If your symptoms are severe or persistent, see a healthcare provider.
Oral rehydration therapy: the science behind the category
Every electrolyte drink on the shelf owes something to oral rehydration therapy (ORT) — one of the most important public-health breakthroughs of the last century. ORT uses a precise balance of water, sodium, and glucose to help the body absorb fluid dramatically more effectively than water alone. It works because of a mechanism called sodium-glucose cotransport: in your small intestine, sodium and glucose are absorbed together, and they pull water across the gut wall with them.
ORT was developed to treat dehydration from illness, and its precise sodium-to-glucose ratio is calibrated for rapid, clinical-grade rehydration. Modern electrolyte supplements borrow the underlying insight for a different, everyday job: replacing the minerals your body loses over a long day, in forms it can absorb well, rather than replicating a clinical formula. Redi is built for that everyday job — the right minerals, in absorbable forms, naturally sweetened rather than glucose-heavy, so what you drink supports steady hydration through a demanding day, not a substitute for treating acute illness.