Everything Cyclists Need To Know About Staying Hydrated

Note that this post contains affiliate links and we may earn a small commission at no extra cost to you if you buy something.

Everything Cyclists Need to Know About Hydration

Whatever you do in a routine, you wish to do with comfort and spontaneity. With no inconvenient breaks to detract you or steal your attention from the important task at hand. For cyclists, one of the primary factors that make for a more rewarding, more comfortable, and more seamless ride is staying properly hydrated.

So let’s look into why hydrating really is important, to begin with, and by further exploring into the topic of everything cyclists need to know about staying hydrated.

Why hydration is important?

Two aspects run alongside each other in this regard. They may be confused as the same since they are often referred to as one integrated unit.

Psychological aspect

Your brain is supposed to be around 85% water. So it shouldn’t be that much of a surprise when you find that according to one source:

“When your brain depletes 1 percent of water, you’ll likely have a 5 percent decrease in cognitive/brain function; and for some, this is a lot. … Other symptoms of lack of water: Fatigue. Memory problems.”

Students may have experienced this after a long day of playing around and getting a test in the last period. Situations like this can be a serious cause of frustration as the dehydrated cognitive system just can’t function at the same capacity as the hydrated one.

Other than the composition itself, the metabolism of the brain involves using up about 20% of the glucose content of the blood supply. Metabolism uses sugars (mainly glucose) and water to produce energy. The lack of either of these can affect the supply of adequate energy to the brain.

This is why besides poor hydration, low blood sugar may also dramatically affect the ability to think, reason, focus, and use other cognitive facilities.

Physical aspect

Many of you may have heard the saying ‘Water is the stuff of life.’ That’s exactly the case within your body. According to an article on www.usgs.gov, water makes up more than half i.e. 60% of your body. For a live, healthy body to function its organs need considerable amounts of water circulating in the system to keep the majority (almost all) of the biological process up to speed.

The following are the respective water contents of the major organs as per Howard Hanson Mitchell a.k.a H.H. Mitchell’s “Journal of Biological Chemistry”,

Percentage of water content in body organs

Brain Heart Lungs Muscles Skin
73% 73% 83% 64% 79%


According to Dr. E. Coyle, Ph.D., director of the Human Performance Laboratory at the University of Texas at Austin:

“ Cyclists who lose a quart of fluid experience a rise in heart rate of eight beats per minute, a decrease in cardiac function, and an increase in body temperature. Dehydration may cause increased metabolic stress on muscles and faster glycogen depletion. It also wreaks havoc on your internal thermostat by decreasing blood flow to the skin, slowing your sweat rate, and increasing the time needed for fluids to be absorbed into the bloodstream.”

So hydration is important, and you need to keep an eye on it especially if you lose considerable amounts of fluid during your daily routine.


You might also want to check our detailed article on “Benefits of Cycling“.


How to know if you’re dehydrated?

This question is of the utmost importance when staying hydrated for cyclists or in general, is concerned. Knowing when you are dehydrated can play a significant role in how you approach hydration, and when and how you choose to replenish your body fluids. Being a cyclist, this can make the difference between the gains you experience from your cycling routine, or the lack of gains.

Performance deterioration

As discussed earlier, your body is always in a dire need for a constant supply of water. Any gap in the supply or a decrease in the amount being supplied can seriously affect performance during rides. This includes both physical and cognitive performance (meaning you won’t just tend to cycle slower, you’ll also be slower to react to any oncoming vehicles or obstacles that may show up unexpectedly).

The following table shows descriptive analyses of what would start to happen as your body starts losing water.

Respective effects of gradually decreasing body water content

Percentage of weight loss due to sweating Affects/ Consequences
2% Ø  Noticeable performance impairment
4% Ø  Decreased capacity for muscular movements
5% Ø  Heat exhaustion

Ø  Drop in performance capacity by about to 30%

7% Ø  Hallucinations
10% Ø  Circulatory collapse, heart stroke, the eventual possibility of death.


Color intensity

The color of urine is one of the most obvious and accurate representations of how low or abundant your body is on water.

Generally speaking, the paler or the lighter the coloration of the urine is, the more abundance there is of water inside your body. This may not be the case for patients of diabetes insipidus or for people with related diuresis issues but for people with healthy bodies, color is a good indicator of the level of hydration.

The following table should help get a clear picture of how concerned you should be about the different colors of urine :

What colors of urine may be indicating

Urine color What it’s supposed to mean
Clear\ transparent Ø  Too much water in the body.

Ø  Should consider cutting back.

Yellow Ø  Moderate.
Amber Ø  Moderate but be cautious not to push it to orange.
Orange Ø  Cause for concern.

Ø  Should start drinking more

Dark brown Ø  Cause for unsettling concern.

Ø  Serious dehydration probable.



Water or processed fluids?

Importance of Hydration for Cycling

The commercialization of everything we use in our everyday lives also extends into hydration. With several energy and sports drinks roaming around the market, you may start to wonder if plain old water really is the best to cater to your needs.

The research doesn’t have to go too deep to show that water is supposed to be an irreplaceable reservoir for human beings. This has to do with both the chemical nature and the economy associated with plain water. But the work done on making sports drinks more efficient has shown some positive results in related research.

For example, research conducted by Dr. E. Coyle ( who has been mentioned above as well) compared the ‘replenishing capabilities’ of different sources of hydration which included three different agents. These were plain water, diet coke, and sports drinks.

In the experiment, athletes were to consume 2 liters of fluid 2 hours after exercising. One group was to resort to diet cola, another was to use energy drinks and the last was supposed to use sports drinks.

The results showed that

  • Diet Cola replenished about 54% of body fluids.
  • Water replenished about 64% of body fluids.
  • Sports drinks replenished 69% of body fluids.


The results showed that where ‘replenishing capacity’ is concerned, the order comes out to be:

Diet Cola< Water< Sports drink


Recommended Read: Should you take a pre-workout before Cardio.


The science behind good hydration

The idea behind why some drinks are better for fluid replenishment than others is strongly associated with osmosis and electrolytes.  Knowing these terms and how they affect your body is key if you want to know about how best to hydrate your body. This is one of the important things a cyclist must know about.

What are electrolytes and how are they important?

Sticking to the strictly chemical definition:

Electrolytes are substances that break up into their components when they’re dissolved in a polar solvent (such as water).”

They are generally salts and some of the electrolytes that are important to human metabolism are sodium, chloride, potassium, calcium, magnesium, zinc, iron, etc. Sodium is supposed to be of paramount or primary importance. Some of the roles of sodium include:

  • Nerve impulse conduction/ cognitive and reflexive ability
  • Fluid retention and absorption
  • Stimulating thirst
  • Improving fluid palatability ( the satisfaction you get by drinking fluids)

Salts are a paramount factor in hydration. The answer to how is osmosis.

Osmosis is the movement of water (or any other solvent) through a semi-permeable membrane from a solution of lower concentration towards a solution of higher concentration.

In order for your body to be hydrated, it needs osmosis to play its part. And for osmosis to play its part, the body needs for the incoming fluids to have the correct balance of electrolytes relative to the fluids already present inside the body (as the cause for movement of water is the relative concentrations of electrolytes in the cells of the body vs in the fluid surrounding the cells).

An incorrect balance (of electrolyte concentration) between incoming fluids and the body’s own fluids makes for poorer hydration or in extreme cases, even dehydration. This is why drinking super-saturated salty water (like seawater) makes you thirstier than you were before. The concentration of the incoming fluid’s electrolytes, in this case, is higher than the fluid already present in the body so rather than shifting into the body’s cells, it moves water out of cells. And that’s made possible by electrolytes or their relative concentration.

So If the fluid in the body has a lower concentration of electrolytes (or dissolved salts) relative to incoming fluids, the incoming fluids may cause the already present fluids to flow out of the body’s cells rather than the other way around. Conversely, if you want to get hydrated, the electrolyte concentration in the body’s cells must be higher than that of the fluid surrounding these cells.

All of this implies that there is a constant need for electrolytes along with water itself. This is why the lack of electrolytes in the fluids you drink makes for poorer hydration, which is often reflected by poor fluid palatability or poor satisfactory results from drinking these fluids.

Why plain water isn’t going to cut it.

You see, just drinking pure water is great if you already have electrolyte-rich fluid in the body. Since pure water has relatively low concentration (which is no concentration at all) of electrolytes, it will move into the body cells in accordance with the rules of osmosis. But here’s the catch.

If the fluid inside the body’s cells starts having a smaller and smaller concentration of electrolytes, the pure water will not move into the body cells as effectively as it would when faced with a fluid of high electrolyte concentration. And so as you start drinking more and more of pure water, your body’s inner fluids start losing their natural electrolyte-water balance, and eventually, the body fluids become so electrolyte-poor that osmosis slows down too much for you to hydrate effectively, even if you’re drinking gallons of water. This results in you feeling bloated but still somewhat thirsty i.e. your fluid palatability goes down the slide.

The difference in electrolyte abundance is exactly where better sources of hydration are supposed to stand out. It’s why modern bottled water companies add specific amounts of electrolytes in their product so that the body doesn’t lose too many electrolytes and end up dehydrated.

That being said, it’s always useful to have the saying ‘Too much of anything good is bad’ in perspective. What that means is ‘Drink Electrolyte-rich fluids but don’t overdo it’ with the electrolytes because as already discussed above, too many electrolytes in incoming water (like four spoons of salt in a cup of water) can actually suck water out of the body cells rather than supply water to the body.

The following table should help you decide which type of drink is best suited to your daily regimen:

Type of ride Recommended intake
o   Rides of low intensity less than an hour long ·         Plain water should be fine but supplementing with glucose-rich foods should be great.
o   Rides of high intensity less than an hour long ·         Carbohydrate-rich fluids like energy or sport drinks
o   Rides of low intensity more than an hour long ·         Since you’re going to be sweating a lot, Electrolyte-rich sports drinks should be added into the mix.
o   Rides of high intensity more than an hour long ·         Sports drinks with high sugar and electrolyte content or a mix of glucose-rich content along with electrolyte-rich fluids.


How to hydrate effectively

How to know you are dehydrated for cyclists

Two factors come into play here besides what you’re drinking.

  • When you drink and
  • How much to drink

When to drink

A popular notion might be to fuel up on water a while before the ride. But sources suggest that this is more detrimental or harmful than beneficial. This is because your body doesn’t have a huge hump on it’s back to store water for the long haul. It has limited capacity and will expel the rest. So drinking a lot a few hours before the ride will probably only tend to make you urinate more either before or worse, during the ride.

The best-suggested way is drinking as you go. It goes like this:

  • Hydrate 2-3 hours before the ride with about 500-1000 mL of fluid.
  • Take a few satisfactory gulps of whatever you’re going to drink just before you start (and always have an adequate amount before going to bike for a relatively long ride)
  • Recognize the optimal amount your body can take without having to visit a restroom.
  • Don’t overdo it and drink a few satiating gulps during breaks along the ride.

Always try to drink at the end of the ride as much as you feel like. Electrolyte-rich fluids should be preferred at the end since your body has to restock the electrolytes it lost during the ride. And since you’re off the bike, eating succulent or juicy solids like vegetables and fruits should also be considered. They’re naturally rich in Electrolyte-nutrients as well as being filled with carbs and/or proteins that help in boosting your muscular recovery process.

How much to drink

This is a primary question that should be considered by people that have routines in which proper hydration is required, like people who work out regularly, athletes, etc. It becomes even more important for cyclists, and especially so, when considering the topic of everything cyclists need to know about staying hydrated.

To summarize it, you should try to drink at least about the same amount of fluid that you lose from a ride, assuming that the weight loss is primarily due to heavy sweating and not other metabolic and digestive processes.

The process is pretty simple and you only have to do it once if you a ‘normal’ biking routine in place. All you would do is weigh yourself accurately before the ride, bike according to your normal routine with the exception of not drinking during the ride itself. After the ride, remove any clothing that might still be holding the sweat (so it doesn’t affect the ‘fluid loss’ measurement) and see how much weight you’ve lost.

For your convenience, the equivalent mass/weight and their liquid unit counterparts are:

1 pound = 16 ounces = 453.6 mL

So just see how much weight you’ve lost in pounds, convert it into ounces or mL, and then drink according to how much you’ve lost.

Since slight over-hydration isn’t as hazardous or detrimental as dehydration, you should try and drink a little more than the amount of fluid you lost during the ride but for people on the high end of the weight spectrum that are just starting to bike, replacing all of the fluid might be a dim idea so considering a minimum of 75% fluid replenishment could be helpful.


All of this information combined should help you establish a clear picture of everything you needed to know about hydration being a cyclist. Hence, its more than just recommended to always carry a water bottle when you go out for your cycling errands, or just embark on an exercise routine on your in house stationary bike.

Leave a Comment

Your email address will not be published. Required fields are marked *