Are Energy Drinks Okay If You Workout?

When you're pushing hard in the gym or racing through a trail run, energy drinks look like the quick fix you need. They promise a burst of energy, sharper focus, and even better endurance. But are they actually helping-or hurting-your workout? The answer isn’t simple. It depends on what’s in the drink, when you drink it, and how your body reacts.

What’s really in energy drinks?

Most energy drinks contain three main ingredients that affect your workout: caffeine, sugar, and electrolytes. A typical 250ml can has about 80mg of caffeine-similar to a strong cup of coffee. Some brands pack over 200mg. That’s more than the FDA recommends in a single sitting for adults.

Sugar? That’s another story. Many popular energy drinks have 27g of sugar per can-that’s nearly 7 teaspoons. A 2023 study from the University of Queensland found that athletes who drank sugary energy drinks before endurance training saw a short-term performance boost, but also had higher blood sugar spikes and slower recovery afterward. If you’re working out to lose fat or manage insulin sensitivity, that sugar can undo a lot of your effort.

Then there are electrolytes. Sodium, potassium, magnesium-these help with fluid balance and muscle function. But most energy drinks have just enough to taste good, not enough to truly replace what you lose through sweat. You’d need to drink 3-4 cans to match what’s in a proper sports drink. And that means way too much caffeine and sugar.

When energy drinks might help

There are real cases where energy drinks can be useful. If you’re doing a high-intensity session-think HIIT, CrossFit, or a competitive race-and you haven’t had time to eat, a small amount of caffeine can sharpen focus and delay fatigue. A 2024 meta-analysis in the Journal of Sports Sciences showed that 3-6mg of caffeine per kg of body weight improved time-to-exhaustion by an average of 12% in trained athletes.

That’s about 200-300mg for a 70kg person. So if you’re drinking a can with 160mg caffeine and you’re already used to coffee, it might give you that edge. Timing matters too. Drink it 30-45 minutes before your workout. That’s when caffeine peaks in your bloodstream.

Some athletes also use energy drinks during long events-like marathons or triathlons-when they need quick calories and stimulation. But even then, they often choose versions with less sugar and added electrolytes, not the soda-like brands you see in convenience stores.

The hidden downsides

Here’s what most people don’t think about: energy drinks don’t replace water. They can actually make dehydration worse. Caffeine is a mild diuretic, which means it increases urine production. If you’re sweating hard and chugging a sugary, caffeinated drink, you’re not hydrating-you’re adding stress to your system.

And then there’s the crash. That sugar rush? It doesn’t last. Within 60-90 minutes, blood sugar drops, leaving you more tired than before. For endurance athletes, this can mean hitting a wall mid-run or losing focus during the final stretch.

Long-term use has also been linked to higher resting heart rates and increased blood pressure. A 2025 study from Monash University followed 1,200 regular gym-goers who drank energy drinks 3+ times a week. After 12 months, 37% showed elevated resting heart rates-enough to raise concerns about cardiovascular strain, especially in younger athletes.

And don’t forget the calories. One can of energy drink = 110-150 empty calories. If you’re drinking one daily, that’s over 1,000 extra calories a week. That’s a pound of fat every 3-4 weeks-without even changing your diet.

What should you drink instead?

For most workouts under 90 minutes, plain water is still the best choice. Add a pinch of salt and a squeeze of lemon if you’re sweating a lot. It’s cheap, natural, and doesn’t spike your blood sugar.

If you need more, try:

• Black coffee-no sugar, no additives. About 150mg caffeine per 12oz cup. You control the dose.
• Electrolyte tablets or powders-dissolve in water. Brands like Nuun or LMNT give you sodium, potassium, and magnesium without sugar or caffeine.
• Low-sugar sports drinks-look for under 10g of sugar per 250ml. Some, like Gatorade Zero or Powerade Zero, use artificial sweeteners. They’re better than the sugary versions, but not perfect.
• Coconut water-natural electrolytes, moderate sugar. Good for light to moderate workouts.

For long or intense sessions, consider making your own drink: water + a pinch of salt + a splash of orange juice + a teaspoon of honey. It’s real food, not science lab in a can.

Who should avoid energy drinks completely?

Some people should skip them entirely:

• Anyone under 18-your body is still developing, and caffeine can interfere with sleep, brain development, and heart rhythm.
• People with anxiety, high blood pressure, or heart conditions-caffeine can trigger palpitations or panic attacks.
• Those who struggle with sleep-if you drink energy drinks after 2pm, you’re likely sabotaging your recovery.
• People training for endurance events-relying on sugar-heavy drinks trains your body to burn sugar, not fat. That limits your stamina long-term.

Bottom line: Use them smart, not often

Energy drinks aren’t evil. But they’re not magic. If you’re using them as a daily crutch to get through workouts, you’re missing the point. Real energy comes from sleep, hydration, and balanced meals-not a brightly colored can.

Use energy drinks like a tool, not a habit. Save them for race day, a tough training session, or when you’re truly running on empty. And always check the label: look for under 100mg caffeine, under 10g sugar, and real electrolytes. Anything else? Stick to water.