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Fact checked by Andrew Lenau, ISSA CPT & Sports NutritionistFACT CHECKED
July 06, 2022
As if pre-workout wasn't enough of a kick, gym goers continue finding new ways to improve their workout training performance. This might be done through dry scooping or possibly even taking pre-workout on an empty stomach.
Today, we're going to talk about the latter: If you can, or should, take a pre-workout drink with no food in your belly. We'll review the possible benefits of taking pre workout on an empty stomach, as well as potential side effects and issues. Read on to find out:
Pre-workout is a group of sports supplements meant to be taken before a training session to enhance exercise performance. They can range from a powder mixed with water to traditional medicines that have been converted to sports performance enhancers. Each pre-workout formula will vary based on what ingredients and how much of each are included.
Due to the difference in pre-workout ingredients, the performance-enhancing benefits may come from several mechanisms, such as muscle buffering; however, the most popular reason people take an excellent pre-workout is for enhanced energy.
Some fitness enthusiasts look for a little extra kick when they're at the gym to produce a more challenging workout. This is the sole purpose of pre-workout supplements, and they do a pretty good job.
There are pros and cons to pre-workout supplements, but when taken as directed, pre-workouts have been proven to enhance performance. While above, we mentioned the energy, that's not good for anything if it doesn't produce results. However, this extra energy can result in an improvement in various training variables, including:
Together, all of these can result in increased lean muscle mass growth, which is what we're going to the gym for in the first place. And, the best pre-workout supplements can also help with weight loss due to extra calories burned in the gym, if that's your goal.
Some gym goers swear by fasted training, meaning they work out on an empty stomach, to improve their body composition or athletic performance. Research shows that performing aerobic exercise in a fasted state leads to higher fat oxidation, resulting in more fat burned during your workout1. And if you enjoy cardio first thing in the morning, working out on an empty stomach is more convenient. After all, who wants to cook a meal at 5 a.m. as you're headed out the door?
If you fall into this bucket and enjoy working out in a fasted state, taking pre-workout beforehand can give you some added energy to ensure you're giving your workout your all. Between just waking up and having no new food to use for fuel, pre-workout enables you to increase your energy levels at the gym even though you haven't eaten.
In addition, some gym goers taking pre-workout supplements on an empty stomach feel its effects even more significantly. With no food to absorb the pre-workout powder, it'll likely hit your system faster and more powerfully.
Taking pre-workout in a fasted state is a strategic move that some use to reap a few extra benefits. Considering trying it? Here are some reasons you might want to take your pre-workout on an empty stomach.
Fasted training, which means working out after not eating for some time, is becoming more popular these days. This is particularly true for performing steady-state cardio. As you exercise on an empty stomach, you will use your stored fat for fuel.
Caffeine can increase your body's ability to break down this stored fat, meaning more energy. More energy means you'll perform cardio for longer before hitting exhaustion, leading to more calories burned and an increase in fat loss.
Pre-workout may help with weight loss due to its ability to generate higher workloads at the gym. In other words, if you're moving more, lifting more, and training longer, you will burn more calories.
In addition, if you are training in a fasted state and your body can utilize fat for fuel more efficiently, that's another plus. But, to be clear, it doesn't matter how much fat your body utilizes for fuel if you eat a surplus of calories. That said, if you can train harder with a pre-workout than without, it could improve body composition.
If you're in the process of cutting or losing some unwanted pounds, the calories you burn while exercising can make a huge difference when paired with proper diet. Research has shown that caffeine can promote weight loss while reducing your BMI and body fat2. Many pre-workouts contain caffeine, so that in combination with your body burning more fat exercising in a fasted state, is the perfect combination for supporting weight loss.
Research examining the effects of taking pre-workout supplementation in a fasted state before weight lifting found that it improved participant's overall energy and alertness. When compared to a control group, the pre-workout group also had increases in upper body endurance3. And if you're heading into high intensity exercise on an empty stomach, you'll want that energy burst to push you through your routine.
For those worried that working out on an empty stomach will lead to a dismal workout, research indicates otherwise. The same study that reviewed preworkout consumption in a fasted state found that participants had a higher power output during resistance training3.
When taking preworkout with food in your stomach, the ideal time to take it is 30 minutes beforehand. But when you're taking it on an empty stomach, it will hit you quicker. This means that if you start drinking it during your 10-minute drive to the gym, it'll likely already be kicking in by the time you're ready to take on the bench press.
There are plenty of great benefits with taking preworkout on an empty stomach, but as with any ergogenic aid, there are things to be cautious of. Most of the negatives associated with pre-workout occur in those who have sensitivities to stimulants.
If you get an upset stomach after taking preworkout with a full belly, you will likely experience the same effects taking it in a fasted state. A semi-common pre-workout complaint is that your stomach may burn after taking it due to various gastric distress issues. In addition, it's not uncommon for pre-workout to make you poop.
The bottom line is if you have digestive issues when taking pre-workout on a full stomach, you'll likely have digestive system irritation on an empty stomach. They may potentially be slightly worse, since there is nothing in your stomach to absorb the pre-workout.
The good news is that pre-workout is a great ergogenic aid that boosts your athletic performance in the gym. The bad news is that if you take it before every gym session, the next time you hit the gym without your pre-workout, you'll likely notice that your energy and alertness aren't as great compared to when you take it. A great way to counter this is to take your pre-workout formulas before hard workouts and skip it on lighter gym days or during deloading weeks.
In general, if your preworkout contains caffeine and you are sensitive to it, taking it on an empty stomach can increase those sensitivities. Caffeine gives your nervous system a jolt, which leads to the increased energy. But if you're sensitive to it, you may feel extra jittery and anxious, experience an elevated heart rate, become nauseous, and feel dizzy.
In addition, if you have heart issues, diabetes, any disorders or diseases, or are pregnant, you should always consult your doctor before taking a supplement.
You can take a pre-workout during your feeding window, but what about your fasting window? It depends.
First, if your preworkout has any calories in it, it will technically break your fast. Some fasting purists say that even drinking artificial sweeteners with no calories is off-limits.
One pre-workout ingredient that confuses people is branched-chain amino acids. Many pre-workout supplements will include these in their formula.
However, because branch-chained amino acids aren't technically protein, the FDA does not require them to be counted as calories.
The problem is that they very much do have calories! Protein is just a bunch of amino acids, so it's logical to conclude that if the protein has calories, amino acids must have calories. Many fans of intermittent fasting get caught by this.
However, this will depend on how much of a purist you are and if this is acceptable to you. The answer will vary depending on who you ask.
For reference, 1 gram of amino acids will have roughly the same calories as 1 gram of protein, totaling 4 calories.
One of the major issues we want to point out with this question, which isn't discussed as much as it should be, is why do you feel you need an extra energy boost?
If it's just because you're headed into a hard workout first thing in the morning, we get it, and it sounds like you're using your pre-workout supplements in the right way. However, if it's to make up for a lack of sleep, taking a preworkout on an empty stomach may temporarily solve your problem, but it isn't a permanent solution.
Most pre workout supplements already come with fairly high doses of stimulants. For example, some caffeinated pre-workout supplements will have upwards of 400mg of caffeine. Sorry, but if you need a bigger jolt of energy than that to train hard, there may be some other issues at play.
For example, many people underestimate the importance of sleep. The number of people who only get a few hours of sleep a night and then proceed to wonder why they feel tired at the gym is astounding. So check your sleep and nutrition before looking at exogenous substances to produce enough energy.
In addition, if your current training program is to make strength gains and isn't as focused on weight loss, it's probably a better idea for you to eat beforehand as it ensures your anaerobic energy system has enough fuel in the tank for extra powerful contractions. You don't want to risk protein breakdown when your goal is more muscle mass.
When all is said and done, the question remains: Should you take your favorite pre-workout on an empty stomach? Our answer: It depends on your goals. If you are trying to lose weight, taking pre-workout on an empty stomach can burn more fat while providing you energy that your empty stomach cannot.
If you are weight training to become stronger, your best bet is probably to eat before taking your pre-workout. Between a perfectly portioned macro meal and an extra boost from your supplement, you'll be able to make some serious gym gains. And for those days in which you skip breakfast because you're running late, don't panic. Remember the study we mentioned above? It showed that pre-workout supplements consumed in a fasted state still improved participant's anaerobic power.
Just remember, everything in moderation, and be selective with your preworkout. Do your research on the best pre workout supplements that use good pre-workout ingredients. To get the most out of your pre-workout supplement, it's best to occasionally not use it. That way when you re-start taking it, all of its benefits will once again feel more powerful.
If you're in a fasted state, taking pre workouts 10-15 minutes before exercising is enough time for it to hit your system. If you're training for muscle gains, we recommend consuming it about 30 minutes before a workout, after eating a meal. It doesn't need to be a lot of food, either. A banana or protein shake will do the job.
Professionals have labeled preworkouts as a highly effective sports supplement that can help gym goers reach their fitness goals. If you want to build muscle, it'll help you with muscle building and lean muscle growth. If you're in it for weight loss, it can also aid with that due to its various fat-burning properties.
Its effectiveness is primarily due to increasing your workout energy. It can increase your ability to do whatever it is that you want to do.
To get the most out of your preworkout supplement and time in the gym, make sure you're also getting in all your macros and quality sleep. Also, as a PSA: Drink plenty of water.
Looking for a great pre-workout supplement? Check out the Best Pre-Workout Supplements on the market!
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