Runners are constantly reminded of the importance of hydration. You can spot almost any runner carrying around some sort of water bottle as they go about their day, ensuring they have water at the ready to hydrate before or after their run.
On long runs, hot days, and hard workouts, there’s a good chance that runners will swap out plain water for an electrolyte-containing sports beverage. But does your body need glucose to absorb electrolytes as well?
From Gatorade to Powerade, Honey Stinger to Nuun, there are tons of hydration beverages geared towards runners that help replenish electrolytes lost in sweat to optimize hydration and performance.
If you look at the nutrition label of most sports beverages and hydration products for runners, you’ll see electrolytes like sodium, potassium, and sometimes magnesium and calcium, but many also contain sugar, in the form of glucose, fructose, sucrose, or other simple sugars.
In the current climate where sugar is usually demonized and sugar-free products seem to be all the rage, many runners are left scrutinizing sports beverages labels wondering, “Is glucose an electrolyte?” Does your body need glucose to absorb electrolytes? Will drinking a sports drink with sugar improve my hydration or are sugar-free electrolyte drinks better?
In this guide, we will discuss if glucose is an electrolyte, the evidence for sugar and carbohydrates in sports beverages, and optimizing hydration during exercise.
We will cover:
- What Are Electrolytes?
- Why Do Runners Need Electrolytes?
- Is Sugar An Electrolyte?
- Differences Between Electrolytes and Glucose
- Does Your Body Need Glucose to Absorb Water?
- Does Your Body Need Glucose to Absorb Electrolytes?
- Benefits of Glucose In Sports Drinks
- How Much Sugar Should My Sports Beverage Contain?
Let’s get started!
What Are Electrolytes?
Electrolytes are minerals that have either lost or gained electrons, so they carry an electrical charge. Electrolytes are found in body tissues, as well as fluids like blood, urine, and sweat.
Electrolytes like sodium, potassium, chloride, magnesium, and calcium play key roles in a variety of physiology functions such as nerve conduction, skeletal muscle contraction, and heart muscle contractions.
Moreover, electrolytes have been found to increase the absorption of water; however, they are lost through sweat, which can cause imbalances and deficiencies in runners.
For these reasons, replacing electrolytes in the fluids you ingest before or after running or working out can ensure your body stays well hydrated and firing on all cylinders so to speak.
The minerals for vital electrolytes can be consumed in the diet through foods like fruits, vegetables, nuts, seeds, legumes, and dairy products.
Alternatively, sports beverages, electrolytes tablets, and even pickle juice are consumed by runners and other athletes during endurance exercise to optimize hydration.
Why Do Runners Need Electrolytes?
Electrolytes play several important roles in the body, which is why replacing electrolytes lost in sweat is so important. Functions of electrolytes include:
- Maintaining ideal fluid/hydration levels
- Maintaining optimal pH levels in the blood, urine, and body
- Increasing the uptake of nutrients into cells
- Shuttling waste products out of cells
- Supporting protein and carbohydrate synthesis
- Conducting nerve impulses
- Initiating muscle contraction and relaxation
- Maintaining heart contractions
- Supporting a variety of brain functions
Is Glucose An Electrolyte?
We now arrive at our central questions: “Is glucose an electrolyte?” and “Is sugar an electrolyte?”
The short answer to both of these questions is no. Glucose is not an electrolyte and sugar is not an electrolyte.
Glucose is a simple sugar that is often found in sports beverages because it does seem to increase the absorption of electrolytes.
Therefore, if you drink a sports beverage with electrolytes and sugar, there’s reason to believe your body will better absorb the electrolytes in the hydration beverage than if you drink a sugar-free sports drink containing only electrolytes or artificial sweeteners.
Related Article: The 7 Best Water Flavorings For Your Water Bottle in 2022
Differences Between Electrolytes and Glucose
Electrolytes and glucose or sugar are not the same thing. However, they can work together to improve hydration.
Glucose is an energy-containing molecule. There are four calories per gram of glucose. Therefore, glucose can increase your energy levels.
The brain, neurons, and red blood cells all require glucose for energy, and if your blood sugar levels are low, glycogen stored in the muscles or liver will be broken down to create more blood glucose.
When you are fasting, or have depleted your glycogen stores through endurance exercise, the body will break down muscle tissue for energy.
Electrolytes themselves do not contain calories nor do they generate energy. However, they increase the absorption of water, aiding in proper hydration.
Dehydration is associated with fatigue, poor exercise performance, and sluggishness, so by helping prevent dehydration, electrolytes indirectly support energy levels.
Does Your Body Need Glucose to Absorb Water?
Even though sugar isn’t technically an electrolyte, there is a large body of evidence to suggest that sport drinks that combine carbohydrates (particularly glucose and fructose) with electrolytes can improve athletic performance by optimizing the absorption of water and electrolytes and maintaining metabolism.
Although water can be absorbed without glucose or electrolytes, the body absorbs water faster in the presence of these ions and sugar.
Water is absorbed in the body by osmosis, which means that it moves from areas where there are higher concentrations of particles to ones with lower concentrations.
When there are higher concentrations of electrolytes like sodium and potassium in the bloodstream, along with higher concentrations of glucose, water you drink will move from the small intestines into the bloodstream more easily, hydrating your body more effectively.
Does Your Body Need Glucose to Absorb Electrolytes?
Now that we’ve covered how glucose and electrolytes increase the absorption of water, let’s answer the question: does your body need glucose to absorb electrolytes?
Besides just increasing the absorption of water, sugars such as glucose can further accelerate the rehydration process because glucose activates the receptors in the small intestines that absorb sodium.
These receptors pair glucose and sodium together such that when the transporter proteins that take up sodium are activated when they encounter a 2:1 ratio of glucose to sodium in the small intestines.
Therefore, ensuring there is enough glucose in the digestive tract supports proper uptake of the electrolytes in the sports beverage.
Benefits of Glucose In Sports Drinks
A large review of 50 randomized controlled trials evaluating the effects of ingesting sugar or carbohydrates during endurance exercise lasting longer than one hour concluded that sports beverages with electrolytes and sugar improved performance over electrolyte-only sports beverages or plain water.
For example, electrolyte drinks that also contained carbohydrates increased time to exhaustion in max tests by 2%, and improved performance in time trials at max effort by 15.1%.
Moreover, time to exhaustion following submaximal exercise increased by 7.5% and time trial performance following sub maximal exercise increased by an impressive 54.2% over placebos.
Sports beverages containing glucose or other forms of sugar offer additional benefits over increasing the absorption of water and electrolytes. The carbohydrates can help top off blood glucose levels to preserve muscle glycogen levels and prevent glycogen depletion.
This can be especially beneficial for marathon runners, long runs, and endurance workouts, wherein the body’s limited glycogen stores can be problematic and once used up, can lead to a significant performance decline.
Between the skeletal muscles and the liver, the body can store enough glycogen to support about 90 minutes to 2 hours of intense exercise, depending on your body size, training status, nutritional status, and workout intensity.
How Much Sugar Should My Sports Beverage Contain?
Most studies have shown that you don’t need much sugar to reap the performance benefits of carbohydrates. According to the American College of Sports Medicine (ACSM), ingesting 30–60 grams of carbohydrates per hour during endurance exercise is ideal.
According to the results in the studies considered, the ideal concentration of carbohydrates in these electrolyte drinks is 6-8%, with an overall goal of ingesting 30–80 grams of carbohydrates per hour.
What does this look like practically? How many grams of carbohydrates should your electrolyte drink have?
When the concentration of glucose or carbohydrates is 6-8% in a sports beverage, it means that there are 6-8 grams of carbohydrates per liter.
This is not a significant amount of sugar. There are 4 grams of sugar per teaspoon, so these ideal carbohydrate-electrolyte rehydration beverages have about 1.5-2 teaspoons of sugar per liter. With 4 calories per gram, this sugar concentration equates to 24-32 calories per liter.
While drinking plain water is fine for runs lasting one hour or less, consuming electrolytes and glucose or other simple sugars for intense workouts and long runs is a good way to support hydration.
As proper hydration is not only crucial to peak running performance, but to our health in general, it is very important to ensure we stay well-hydrated at all times.
For more information on hydration, check out the following guides: Hydration For Runners: Everything You Need to Know, Fluid and Electrolytes: A Complete Runner’s Guide and Hydration and Salt Levels For Runners Explained
And if you are looking where to stash this hydration for during your runs, take a look at The 6 Best Hydration Packs For Running.