You are in the middle of your track workout. Sweat is dripping down your face and back. Your leg muscles are screaming from the sprints. It is hard to catch your breath. You are feeling a bit thirsty and reach for…what? Water? Gatorade? Which one should you choose?

Most commercials that advertise sports drinks show professional athletes drenched in sweat on a court, field, or track. Watch any sporting event and you will see the famous “G” on the enormous orange coolers for the players. Run a race and the various replenishing stations offer neon-colored beverages as you jog past. If you read the nutritional label of sports drinks, however, are all those calories and sugar really necessary?

The answer: it depends. Factors such as duration, intensity, weather, and when your previous meal was will affect whether or not you need the extra carbohydrates and electrolytes. First, let’s explore what exactly carbohydrates and electrolytes do in the context of a workout.

Carbohydrates are converted to glucose for energy, which is what helps keep your legs pumping and your arms lifting during activity. There are two types of carbohydrates: complex and simple. Complex carbs, such as those found in whole grains, are digested slowly and keep your blood glucose levels at a relatively steady state. These carbs are typically consumed some time before a workout or as part of post-workout nutrition. Simple carbs, like those found in sports drinks, are digested quickly and provide a rapid release of energy for the body to utilize. These are the types of carbohydrates that you want to consume immediately before or during a workout for instant energy. Typically, an individual does not need intra-workout nutrition unless they are doing activity for more than an hour or if they are working out fasted, meaning they have not consumed anything yet that day. Long durations of exercise or working out on an empty stomach puts the individual at risk for hypoglycemia, or low blood sugar. This can present as shakiness, excessive sweating, dizziness, and/or nausea. These symptoms can interfere with an effective workout, so the individual should consider consuming a sports drink to prevent feeling this way.

Carbohydrates also provide four calories per gram, which is important in the context of a long workout so the body doesn’t start breaking down muscle for energy. It is important to stay fueled for a workout lasting longer than an hour so you don’t become ravenous after or run out of energy mid-workout. Some individuals see the higher calorie counts compared to water and avoid consuming them. In that case, you can dilute a sports drink with water or make your own using a dextrose powder or fruit juice. This would be beneficial for those whose gastrointestinal systems are sensitive to sugar, those on a low-calorie diet who do not want to “drink” their calories, or diabetics who run the risk of becoming hyperglycemic if too many carbohydrates are consumed.

Electrolytes, on the other hand, are found in sports drinks in addition to carbohydrates to aid in athlete performance. The two most common are potassium and sodium, which help keep the individual hydrated during their long workout. During exercise, you sweat out water and electrolytes, which can put you at risk for dehydration. Even just a small dip in hydration status can affect performance in a negative way, so it is important to consume adequate fluids. Since water doesn’t contain any electrolytes, it can actually dilute the remaining potassium and sodium in the blood while creating a very full bladder. Sports drinks have the benefit of replenishing electrolytes while also avoiding the need to consume large amounts of liquid during a long bout of exercise. Another factor to consider is the environment you are working out in. Outdoor exercise, while enjoyable, can also put an individual at risk of becoming dehydrated quicker if it very humid or hot outside. It can be hard to gauge how much fluid is lost through sweat as well since it can evaporate off your skin quicker. A good rule of thumb is to drink 4-6 ounces every 15-20 minutes of a workout lasting longer than one hour. Find a water bottle that has measurement markings to help keep you accountable for your fluid consumption.

Another beverage that’s isn’t technically a sports drink but still contains electrolytes (and maybe some sugar depending on the product) is coconut water. It has a fraction of the calories of sports drinks while still providing adequate potassium for athletes. This may be beneficial for humid days, diabetics, or those not wishing to get their calories from a beverage. It is also not quite as sweet as sports drinks, so dilution is not necessary.

Certain products may also contain caffeine to give an added boost to the individual during their workout. Caffeine has been proven to boost performance when consumed before or during a workout by blocking adenosine receptors. When there is free adenosine in the blood, adrenaline can be released, resulting in an energetic feeling.

In addition to carbohydrates, electrolytes, and caffeine, sports drinks can also contain amino acids. These small molecules are the building blocks of protein and can help spare muscle when working out intensely or for a long duration. Even though research says additional amino acids are not necessary to build muscle if adequate protein is consumed throughout the day on a regular basis, they can still reduce the effect of delayed-onset muscle soreness. Look for leucine, isoleucine, or valine on the label to see if your drink contains these three branched chain amino acids.

The most important thing to remember when choosing a sports drink or water to compliment your workout is to read the label. A workout lasting longer than 60 minutes would most likely require a sports drink for the added carbohydrates. If you are working out in a humid environment or are sweating a lot, electrolytes are important. Caffeine is an added benefit to those seeking an extra surge of energy during exercise. If muscle soreness is a problem, look for a product containing amino acids. No matter what, always remember to keep adequately hydrated during exercise to prevent fatigue, cramping, dizziness, and/or fainting. Enjoy your workout!