Last Updated on 15 September 2026:
In the pursuit of personalising cycling training and nutrition, hydration is often overlooked. It is a fallacy to believe that we all have the same needs, and a personalised hydration strategy can be a big win for cyclists looking to become more complete. With the help and input from good friend Andy Blow at Precision Hydration, this post explains how to get started.
Covered in this blog:
- The basics of hydration
- Homeostasis
- The trouble with dehydration
- The trouble with overhydration
- What goes out must come back in (at some point)
- Hydrating for recovery
- How to rehydrate properly during your recovery
- When sweat losses are low
- When sweat losses are high
- How to rehydrate properly during your recovery
- Your personalised hydration strategy
- Tips for staying hydrated
The basics of a personalised hydration strategy
Around 60% of the human body is made of water. Water also helps our body flush out toxins, regulate blood pressure, heart rate, body temperature, and metabolism, and we can only survive around three days without water.
From an athletic point of view, hydration theory has developed a lot over many years, and while we can’t pretend to know everything about it, we can safely say we can offer a far greater amount of information, which you can use to start to develop a personalised hydration strategy.
Homeostasis
Hydration has a lot to do with homeostasis. Homeostasis is defined as:
“the tendency of the body to seek and maintain a condition of equilibrium or stability within its internal environment when dealing with external challenges.”
Many critical attributes within our bodies are controlled homeostatically – core body temperature and blood pH levels being two of the better known examples – with body fluid balance being another that is tightly regulated this way. This is of specific interest to athletes.
The trouble with dehydration
Back in the day, Le Tour used to be won by the cyclist who drank the least fluid on the bike. No joke, this was the best hydration practise at the time. Thankfully, we have moved on a lot more since then – as has sports science in general.
However, most athletes who have ever wanted to ride either lighter or more aerodynamically have made the mistake of not taking enough water. This can be catastrophic to performance and has a number of quite significant symptoms that make it just not worth it.
Here are some of the symptoms of dehydration:
- Feeling thirsty
- Dark yellow and strong-smelling pee
- Feeling dizzy or lightheaded
- Feeling tired
- Dry mouth, lips, and eyes
- Peeing less and fewer than 4 times a day
- Maybe most crucially, athletic performance can drop by up to 45%
Based on this scary list of challenges that occur when dehydrated, you’d be forgiven for incorrectly assuming that hydrating a lot more is the solution to hydrating well.
The trouble with overhydration
If dehydration doesn’t relate to you – or maybe it does, but you’ve since started drinking far more water – then overhydration, or hyponatremia, might.
In my experience as a coach, cyclists who have experienced troubles with dehydration – those heavy-sweaters such as Andy and I – have a habit of going over the top to try to eliminate the chance of dehydration. Similarly to dehydration, though, overhydration has some significant symptoms that make spending a little time personalising a hydration strategy even more worthwhile.
Here are some of the symptoms of (overhydration) hyponatremia:
- Nausea and vomiting
- Headache
- Confusion
- Loss of energy, drowsiness, and fatigue
- Restlessness and irritability
- Muscle weakness, spasms or cramps
- Seizures
- Coma
- Significantly impaired athletic performance
What goes out must come back in (at some point)
There’s a fair bit of controversy in sport and exercise science about exactly how much (and what) athletes need to drink in order to maximise performance when they’re sweating. There’s not an easy ‘one-size-fits-all’ rule that can be applied to all athletes in all situations.
However, what most experts can agree on these days (for the most part) is that prolonged exercise nearly always ends up in some level of uncorrected dehydration. People rarely drink enough to replace 100% of their sweat losses (and they probably shouldn’t try to) and, as a result, post exercise rehydration is extremely important because this is when the body is best placed to rebalance its fluid and electrolyte levels.
100% of your sweat losses (both fluid and sodium) need to be replaced at some point if your recovery is to be considered ‘complete’. Complete recovery is essential before you go out again, that’s if you want to perform at your best. If you don’t fully recover, it’s highly likely you’ll run into problems when you try to dig deep.
Personalised hydration strategy for recovery
One of the biggest problems with being a cyclist is that it involves a lot of sweating. If you’re working hard – or the temperature is hot enough – sweating can have a pretty dramatic and disruptive effect on your body fluid and electrolyte balance in a short space of time.
It’s easy to see that even a few hours of training can double, triple or even quadruple your daily fluid turnover. If you’re smashing out a really big day of training, or competing in something like a Gran Fondo or Sportive, your accumulated sweat losses can be huge.
Fluid loss isn’t the only thing to consider when we sweat a lot either. There’s a large amount of sodium in your sweat, so there’s a need to replace sodium as well as fluids when your sweat losses start to get quite high. The exact amount varies considerably from athlete to athlete, which is why you should look at personalising your hydration.
All this matters if you want to be able to continue to perform well in training; optimising your recovery for cycling training is one of the most important ways to see consistent improvements.
How to rehydrate properly during your recovery
The best way to rehydrate after exercise is basically dependent on two key things…
- The level of dehydration you’re at when you finish
- How soon afterwards you need to be 100% ready to perform again
When sweat losses are low
When your sweat losses have been fairly low (as is the case after many ‘standard’ training sessions) and when you don’t need to perform again for a while, simply drinking and eating normally is usually enough to replace all of the fluids and electrolytes you lost.
Homeostasis stimulates you to drink to satisfy your thirst, you get a bit of sodium from your food, and your body does it’s rebalancing act with what you consume and pee out. Before you know it, everything is back to normal.
When sweat losses are high
However, when your sweat losses are high, or you have to restore fluid balance rapidly because you’re exercising again later in that day, a more proactive approach to rehydration may be needed to help your body restore equilibrium in a short space of time.
Fortunately, this has been the subject of a lot of research over the years. The scientific consensus is pretty clear and summarised nicely in a comprehensive review of all things hydration written by Asker Jeukendrup and Lindsay Baker in 2014. They concluded that if you want to rehydrate quickly in a situation where you have become quite dehydrated, or need to be back on top form again very soon, then you need to drink about 1.5 times more fluid than you have lost, and you need to make sure there’s plenty of sodium either in or with the fluid to account for the salt loss too.
The reason you need to drink so much more than you sweated out is that you inevitably end up peeing some of it out (and perhaps continue sweating after you finish too). Your drinks need lots of sodium in them to prevent your blood sodium level dropping too low, which – according to the negative feedback loop – would cause your kidneys to significantly ramp up urine production, negating the effects of putting the fluid back in in the first place!
Experience has taught us that drinking fluids containing sodium can also help if you’ve ever had the misfortune of cramping up during the night after an intense workout.
Your personalised hydration strategy
To get started with your personalised hydration strategy, take PH’s free online sweat test. Coach Pav clients get 15% off their PH products too!
Clients, please check ‘YOUR COACHING GUIDE’ for the code.
Tips for staying hydrated
It’s all very good staying hydrated when you’re on your bike, but general day-to-day hydration will be crucial to getting this right. Here are my top tips for staying hydrated:
- Drink from a reusable bottle (or your bidon) every day
- Take small sips of fluids frequently
- Add lemon, lime, berries, or cucumber to water instead of purchasing flavoured drinks
- Set an alarm on your phone to remind yourself to drink regularly
- Eat foods with a higher water content, such as melon, cucumbers, grapes, or tomatoes
Summary
Use the principles here to learn from your own sweat losses, practise your plan in training and arrive at key rides better prepared. If you would like support tailoring the wider picture around your training, nutrition and recovery, Book a Free Consultation.
