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It's hot everywhere right now.
Dubai is pushing 42°C. London just recorded its hottest May day in 80 years at 35.1°C. Much of Europe and the US is dealing with record heat.
And if you haven't noticed, the way your body feels when it's hot is completely different.
You're more lethargic. Your training feels harder. Your mental clarity tanks. Recovery suffers.
Most people blame the heat itself.
The reality is usually simpler: they're dehydrated.
You're not thirsty. So you assume you're fine.
But by 3pm, you can barely keep your eyes open. You blame the heat. You blame the humidity. You blame the workout.
You don't blame the fact that you've had one cup of coffee and maybe half a glass of water since you woke up.
I see this constantly, especially when temperatures climb. High-performers crushing it in every area except the most basic one: hydration.
Here's what most people don't realize: your thirst mechanism is a terrible indicator of hydration status.
By the time you feel thirsty, you're already 1-2% dehydrated. That doesn't sound like much, but research shows that even mild dehydration impairs cognitive performance, mood, and concentration.
Your brain is 75% water. When you're dehydrated, blood volume drops, your heart works harder to pump oxygen, and the result is fatigue and difficulty focusing.
When it's hot outside, this gets exponentially worse.
You're losing water through sweat. You're not replacing it consistently. Your core temperature rises. Your performance tanks.
Studies show dehydration reduces cognitive performance by 10-15%, particularly in tasks requiring attention and focus. Add heat to the equation, and physical performance drops even faster.
Most people are chronically operating in this deficit without realizing it.
You think you're tired from the heat. You're just dehydrated.
Hydration isn't about chugging water when you remember. It's about drinking consistently throughout the day so you never hit that deficit.
This is even more critical in heat.
1. Drink consistently, not reactively
Research on hydration timing shows that consistent intake throughout the day maintains cognitive and physical function better than large amounts consumed sporadically.
Target: 500-750ml in the morning, then another 500-750ml between lunch and 3pm. Sip throughout, don't chug.
In hot weather, increase this. Add another 250-500ml if you're training or spending time outdoors.
2. Consider electrolytes if it's hot or you're active
Water alone isn't always enough, especially in heat. Electrolytes help your cells actually absorb the water you're drinking. Research shows that beverages with electrolytes improve hydration status more effectively than plain water, particularly during exercise or heat exposure.
If you're training, sweating heavily, or living in a hot climate, add a pinch of sea salt to your water or use a sugar-free electrolyte supplement.
Your muscles need sodium. Your brain needs potassium. Sweat loss during heat exposure depletes both.
3. Avoid large amounts of water with meals
Drinking large amounts of water during meals can dilute digestive enzymes and impair digestion. Sip small amounts if needed, but save your main hydration for between meals.
4. Use visual cues
Keep a water bottle on your desk. Set reminders for 11am and 2pm. Make it automatic. In heat, add a 4pm reminder too.
Most of my clients notice changes within 2-3 days of consistent hydration.
The afternoon fog lifts. Headaches reduce or disappear entirely. Focus improves. Energy stabilizes. Training performance goes back to normal.
One client messaged me last week during the Dubai heat: "I thought my training performance was just suffering because of the heat. Turned out I was just dehydrated. Fixed my water intake and I'm back to normal."
The people who stay sharp when it's hot don't dramatically change their routine. They just start drinking water consistently instead of waiting until they're thirsty.
I see this pattern constantly, especially right now with the heat.
Someone's training hard. They're eating well. They're sleeping fine.
But their performance is tanking. They're foggy in the afternoon. They're getting headaches.
And they're looking for complicated solutions. New supplements. New training protocols. More sleep.
Meanwhile, they're drinking one coffee and maybe a glass of water before lunch.
The problem isn't complicated. The solution is even simpler.
Drink water consistently throughout the day. Add electrolytes if you're sweating. Stop waiting until you're thirsty.
Most people make this one change and everything shifts.
The 3pm crash disappears. Training feels normal again. Recovery improves. Mental clarity comes back.
Not because the heat went away. But because they stopped operating in a constant state of mild dehydration.
The irony is that when it's hot - when hydration matters most - most people actually drink less consistently.
They get busy. They think they'll drink more later. They don't want to be running to the bathroom constantly.
And their performance suffers for it.
Right now, with temps breaking records globally, this isn't a nice-to-have. It's essential.
Hydration is the difference between performing at your best and just trying to get through the day.
Want to go deeper?
🎧 Ep 470 - Why You're Drinking Water Wrong - RNT Podcast - I break down why your thirst mechanism is a terrible hydration indicator and the 4 key principles for proper hydration
Cognitive Performance and Dehydration - Meta-Analysis - Review showing how dehydration as small as 2% impairs attention, psychomotor, and immediate memory skills
See you Friday,
— Akash
