Hydration of the body is a very important concept when cycling. It may seem that there is absolutely nothing complicated here, just drink water when thirsty, and that’s it. In fact, everyone is a little different. So, let’s find out how and how much water you need to drink on a bicycle.

Why It’s Important to Drink While Cycling?

Fluids leave our body in three ways: through sweating (due to the work of muscles, the body temperature rises, which needs to be lowered; this is also typical for winter), with urine, and also through the lungs when we breathe.

At 2% fluid body mass loss you can start to see a reduction in performance.  Source

Hydration packs are great for mountain biking
Hydration packs are great for mountain biking

The Effect of Temperature and Humidity

I know this is going to sound obvious, but higher air temperatures will increase the rate you’re going to sweat and lower humidity levels will help cool you during a ride.  The tough combination is when it’s high temperature and low humidity.  Dehydration can quickly creep up on you because you’re not feeling wet from sweat.

Plan to Drink Before You Ride

Many cyclists prefer to drink as much as possible before a ride.  This seems a little arbitrary, the amount of water or electrolyte drink a cyclist need is highly variable, depending on temperature, humidity and planned exertion.

Which is why an individualized hydration plan is ideal. Check out the before and after test farther down in this article. But when an individualized plan isn’t available, the amount of needed tends to range between 1.2 to 2 Liters of fluids per hour of exercise.  (40 to 67 ounces per hour of exercise)

Water is always a great choice for cyclists, especially before your ride. Drink 12 to 16 ounces of water 4 to 6 hours before you cycle and another 12 ounces 2 hours before. If the weather is extremely hot, consider drinking more.

DIY MTB Pro Tip: I’m not saying this is for everyone but studies have shown that caffeinated drinks can improve endurance by 2-4% Source

How Much While Riding

You’ll want to practice habitually drinking small amounts every 10 to 15 minutes during your workout. This helps replenish the water you lose through sweat, keeps you focused, and improves stamina.

How much you drink during a ride depends on the length of your ride.

Shorter Rides Under an Hour

You should focus on replenishing liquids during sessions shorter than 1 hour. Bring a water bottle (20 oz) or an electrolyte-rich drink along for the ride.

For Medium Length Rides 1-3 Hours

Plan for a couple bottles (up to 40 oz) that provides carb replacement. Make sure you drink more often than just when you’re thirsty to stay hydrated until the finish line.

What I Drink Before and During a Ride?

Pre-Ride – I am personally a water guy.  Most of my rides are less than two hours and my pre-ride water intake is 16 ounces of water before a ride with a half of an apple or melon slices (8 ounces) 30 minutes before hopping on the bike.

During that 2 hour ride I’ll drink 32 ounces (less than a liter) of water.  I carry a couple water bottles mounted to my bike frame if I know I’ll be on a dirt road, but will take my hydration pack if I’m hitting the trails.

Using Hydration Pack Mountain Biking
Using Hydration Pack Mountain Biking

Can You Drink to Much?

Overhydration is called hyponatremia. It occurs when athletes drink even when they are not thirsty.  This is the key learn how to sense your thirst.  Test by weighing before and after exertion.  Even if you drink during your ride SUBTRACT that water weight, during the post ride weigh in.  Source

Hydration and Nutrients After a Ride

After sweating it out on your favorite trail, you need to replace the nutrients you lost. Recovery hydration should focus on:

  1. Restoring normal carbohydrate levels with high energy drinks
  2. Protein for muscle repair.
  3. Stop nutrient breakdown.  Transition from burning energy to replenishing

Electrolyte-rich drinks help replenish salts and nutrients lost in while sweating. Without electrolytes, cyclists may experience severe muscle cramping due to low internal sodium levels. Meanwhile, protein can come from drinks like milk or from the meal you should be having within 2 hours after you cycle.

DIY MTB Pro Tip: Carrying all this water can be tough. Get a hydration pack, it’s going to be a game changer for most mountain bikers. I’ve got a guide 👉 Hydration Packs for Mountain Bikers

Learn More About Endurance Activities

The American College of Sports Medicine has a great YouTube webinar that focuses on endurance activities. 

Test for Water Loss During a Ride (Sweat Rate)

This is basically a before and after test.   The idea is this, Hydrate yourself like you normally would before a ride.  Accurately weigh yourself, then go for a 60-minute ride exerting yourself as you normally would during a ride.  Don’t drink during the ride – not a drop.  (I take water if I over exert myself)

After the ride hop on a scale and again accurately weigh yourself again.  I’ve personally seen a weight drop of over a pound. Which means I lost more than 16 ounces of fluid due to sweat.

Below is a weight loss to fluid volume table

Pounds (weight loss)Ounces (fluid loss)
116 oz
1.219.2 oz
1.422.4 oz
1.625.6 oz
1.828.8 oz
232 oz
348 oz

Please note if your fluid loss is more than 2 % of your body weight you will start to see negative affects on performance.  As an example, I’m just over 156 lbs. which means slightly more than 3 lbs. of weight loss during a ride is going to slow me down. Source

With an understanding of your sweat rate, you can plan for how much water you should drink during a ride.

Hydration Tips for Cyclists

  • Ease of Use, have water in a convenient location.  You should never hesitate to grab a drink because it’s to difficult to get the bottle.
  • Gulps or sips, steading sipping during a ride is best. 
  • Straws, Sprays or Bottles, this is a personal preference, a mountain biking bladder pack is nice for ease of use.  Road cyclist often have an ease time grabbing a bottle from a frame holder.
  • Urine Color, Dark urine is a sign of dehydration.  Start a ride hydrated with light colored urine.

More Ways to Stay Safe On Your MTB


David DIY MTB

David Humphries is the creator of DIY Mountain Bike. For me a relaxing day involves riding my mountain bike to decompress after a long day. When not on my bike I can be found wrenching on it or casting a fly on a small mountain stream. Read more about David HERE.

Sources

  1. Bicycling Complete Book of Road Biking Skills, Jason Sumner, Accessed August 13, 2022.  https://www.google.com/books/edition/Bicycling_Complete_Book_of_Road_Cycling/dTt9DAAAQBAJ?hl=en&gbpv=1&dq=road+biking+skills&printsec=frontcover
  2. “Cycling Hydration 101”   EMMITT SMITH GRAN FONDO, Accessed August 13, 2022. https://emmittsmithgranfondo.com/cycling-hydration-101-tips-to-help-improve-performance-for-cyclists
  3. “Mild Dehydration and Cycling Performance During 5-Kilometer Hill Climbing” National Library of Medicine, Accessed August 13, 2022.  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3867084/
  4. “International Society of Sports Nutrition: Caffeine and Exercise Performance” Journal of the International Society of Sports Nutrition, Accessed August 13, 2022 https://jissn.biomedcentral.com/articles/10.1186/s12970-020-00383-4
  5. “ Can Athletes Drink Too Much Water”  Winchester Hospital, Accessed August 13, 2022.  https://www.winchesterhospital.org/health-library/article?id=13802