Welcome to Beneficial Or B.S.?, where we investigate the health and fitness trends that are all over social media to determine whether theyre actually worth trying.

Optimizing your workout is a phrase that is often used to sum up making the most of exercise, whether that means running faster or more efficiently to target a specific muscle group.

One way that some people try to optimize their fitness regimen is through the use of pre-workout energy drinks from brands like Celsius and C4 Energy, which claim to be healthier than regular energy drinks, and help you have your best workout after drinking them. Specifically, Celsius says it accelerates metabolism and burns body fat. Many people also use them to feel more alert and focused during exercise.

But can a drink really do this? Or is it just the workout itself contributing to these changes in your body and mind? Are there any downsides to these drinks?

Here, experts share what to know and some of the dangers associated with them.

What is a workout energy drink?

These workout drinks are popular among fitness enthusiasts and elite athletes who are seeking to improve their strength, power, agility or speed, said Emma Laing , the director of dietetics at the University of Georgia.

While this is the traditional use of these drinks, they are also consumed as a thirst quencher by people who like the taste and the boost of energy they get after a few sips, she added.

The exact makeup of these workout energy drinks varies by brand, but Dr. Scott Jerome , a sports cardiologist at the University of Maryland Medical Center, noted that they often contain some mix of caffeine, green tea extract, guarana (which is like a natural form of caffeine) and taurine (which supports the heart and brain, and can help nerve growth).

The amount of each additive is generally not spelled out on the label, but most of these drinks advertise that they have about 200 milligrams of caffeine. For reference, an eight-ounce cup of coffee has 80 to 100 milligrams of caffeine. So youre getting much more of an energy boost after drinking one of these.

What do these drinks do?

Workout energy drinks claim to deliver a competitive edge that leads to improved energy levels, metabolism, body composition and athletic performance, Laing said. All in all, they tout making you a better athlete during your workout.

People who use them to get that workout boost generally drink them 30 to 60 minutes before exercising to give the ingredients time to fully kick in.