Both, and for different reasons — but if you only do one, do it during. Drinking to replace losses while they are happening beats catching up at either end, because the deficit you are trying to avoid builds through the session rather than arriving at the finish.
Before is about starting level. During is about not falling behind. After is about closing a gap you already have. Those are three separate jobs and most advice muddles them.
The short version
| when | what it is for | who needs it |
|---|---|---|
| Before | Starting the session already topped up | Anyone training in heat, or fasted, or early in the morning |
| During | Replacing losses as they happen | The highest-value one for anything past about an hour |
| After | Closing a deficit you finished with | Long, hot, or heavy-sweat sessions |
| Not at all | — | An ordinary indoor hour. Water is fine |
Before: get to the start line level
The point of drinking beforehand is not to load up. It is to avoid beginning already behind, which is a surprisingly common way to make a session harder than it needed to be.
Most people who train early are mildly short on fluid simply because they have been asleep for eight hours. Add a hot room, a fasted session, or a night out, and the starting deficit is real before you have done anything.
Practically: a normal drink of water in the 30–60 minutes before, with sodium in it if the session is going to be long or hot. Nothing dramatic. If you are doing an ordinary indoor hour, plain water and a glass of tap water is the whole protocol.
What not to do: hammering a litre in the ten minutes before you start. It does not get absorbed in time, and you will spend the first twenty minutes aware of it.
During: the one that actually matters
This is where the money is, and it is the phase most people skip.
The reasoning is simple. Losses accumulate steadily through a session; the body does not wait until the end to notice. Replacing as you go keeps the deficit small throughout, rather than letting it grow and then trying to reverse it afterwards.
Why bother? Because letting the deficit grow has a measured cost, and it is not evenly distributed across what you can do. Pooled evidence across 28 studies puts the hit at roughly 8% on muscular endurance and 5% on strength, while explosive efforts like a vertical jump came through largely untouched. Better-trained athletes held up better than untrained ones.
So the practical read: if your session is long, repeated, or under sustained load, this is worth managing. If it is short and explosive, it matters less than the marketing would have you believe.
Practically: for sessions past roughly an hour, or anything hot, sip steadily rather than drinking in large amounts occasionally. If you are sweating heavily enough to taste salt or leave marks on your kit, that fluid should have sodium in it.
Under an hour indoors, none of this applies. Drink when thirsty and get on with it.
After: closing the gap
Useful when you finished genuinely down — a long ride, a hot match, a session where you lost noticeable weight in sweat.
The thing worth knowing is that plain water is not the most efficient way to do it. Sodium is what allows fluid to be retained rather than passed straight through, and it works best alongside a little carbohydrate: the two are absorbed together and water follows them. That is why rehydration formulas are faintly salty and slightly sweet.
Practically: drink to thirst plus a bit, with something salty either in the drink or on the plate. A meal does a lot of this work by itself, which is why "have dinner" is underrated post-exercise advice.
What about pre-workout products?
Different category, easily confused with this one.
A pre-workout is usually built around stimulants and performance ingredients. A hydration product is built around fluid and minerals. They can overlap — ours contains caffeine, which is why it doubles as a pre-workout for some people and is a poor idea before bed for others — but they are solving different problems and the labels rarely say so.
If your goal is hydration, judge it on sodium. If your goal is stimulation, judge it on caffeine content and what else is riding along. Do not assume a product doing one is doing the other.
Frequently asked questions
Should I drink electrolytes before or after a workout? During is the highest-value moment for anything long or hot, because you are replacing losses as they occur. Before helps you start level; after helps you close a gap you finished with.
Do I need electrolytes for a one-hour gym session? Usually not. Water covers an ordinary indoor hour. The case for electrolytes grows with heat, duration and how heavily you sweat.
Can I drink electrolytes every day? Most people can, but if you are watching sodium for medical reasons, that is a conversation for your doctor rather than a supplement label.
Is it better to sip or to drink it all at once? Sip through the session. A large volume at once is less well absorbed and more likely to sit uncomfortably.
Does it matter for strength training or just endurance? The measured effects are on endurance and strength, with endurance hit harder. For a short heavy session in a cool gym, hydration is rarely the limiting factor.
What about first thing in the morning? You wake mildly short on fluid, so a glass of water before training is sensible. Whether it needs minerals depends on how long and how hot the session is, not on the time of day.
Where Snake Oil fits
370mg of sodium and 5g of carbohydrate per stick, which is the pairing that actually supports fluid retention, plus potassium, magnesium, zinc, the complete B lineup with vitamins C and E, and a glutamine-led blend.† One stick in 16 ounces of water.
It also carries 100mg of caffeine — roughly a cup of coffee. For a morning or midday session that is a feature. For an evening one, take your own tolerance into account.
†These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
Related reading: Best pre-workout: what the evidence actually supports · Best electrolyte powder: how to actually choose one · Post-workout recovery drink: what actually matters · The long-day playbook