Care for a splash of insight?
Hydrate smart: Before, during, and after you perform. Smart hydration hacks to help your body absorb water, stay in the zone, and fight off fatigue.
Water is life’s fuel, and anyone who trains or exercises knows how crucial it is.
How Much Water Do You Really Need?
We always hear “stay hydrated,” but how much water is enough—especially if you’re active?
A good rule of thumb is to aim for around 30 to 40 millilitres of water per kilogram of body weight each day. For example, someone who weighs 60kg would need roughly 1.8 to 2.4 litres daily, which is typically enough to stay well-hydrated.
Our bodies constantly lose water—through sweat and even breathing—so it's important to keep replacing it. This becomes even more crucial during exercise, when fluid loss increases significantly.
To stay properly hydrated, people need to adjust their water intake based on how active they are. The more you move and sweat, the more you need to drink. Paying attention to thirst, sweat levels, and even the weather can help you know when it’s time to up your hydration.
The Hydration Shift During Exercise
There are several factors that influence hydration during exercise—such as the duration of the workout, temperature, and weather conditions. All of these affects how much fluid you lose and, in turn, how much you need to replenish. The reality is, our bodies are equipped with an incredible built-in system: thirst. It’s a natural, instinctive signal designed to guide us. When you pay attention to it, it’s hard to go off track.
I don’t believe in forcing hydration before you actually feel thirsty during exercise. Instead, I recommend simply drinking when thirst kicks in. Don’t delay—just take small sips when you feel the need. Consistently sipping throughout your session usually keeps things in check.
It's important to understand that you’ll rarely replace all the fluids lost during exercise in real time. Most people finish a workout or race slightly dehydrated. That’s completely normal—and that’s where post-exercise recovery and proper rehydration come into play.
Getting Fluids Back: Why It’s Essential After Exercise
Overhydration can be even more dangerous than dehydration. It can lead to a condition called hyponatremia, where the balance of electrolytes in the body is disrupted, potentially resulting in serious health complications—even death in extreme cases.
If you finish a run and notice you’ve lost 2kg, that doesn’t mean you should immediately drink two litres of water to replace it. Rehydration is a gradual process—it shouldn’t happen all at once. Flooding your system too quickly can be counterproductive. Instead, aim to rehydrate steadily over the next few hours, allowing your body to properly absorb and restore what it’s lost.
Plain water doesn’t absorb into the body as efficiently as fluids that contain a small amount of sugar and salt. These added elements help speed up absorption, making hydration more effective—especially during or after intense exercise.
The key is understanding how much hydration your body actually needs and then matching your fluid intake accordingly. It’s not about drinking large amounts all at once—your body simply can’t absorb it that fast. Hydration is a gradual process, and trying to overload your system won’t work.
During exercise, this slow absorption creates what’s often referred to as the “washing machine effect”—that uncomfortable sloshing feeling in your stomach when fluids aren’t being processed quickly enough. Managing your intake in smaller, consistent amounts helps prevent that and keeps hydration on track.
If you drink too much while running, you might feel or hear a sloshing in your stomach. That’s a sign the fluid isn’t being absorbed and is just sitting in your gut. When that happens, it’s best to pause drinking, take in a bit of salt, or eat something small to help absorption. Once the sloshing subsides, you can continue.