Written by Garett Reid | NSCA, CSCS, CISSN, M.S.E.S.S
Fact checked by Andrew Lenau, ISSA CPT & Sports Nutritionist
FACT CHECKED
We may earn a commission on purchases made through links on this page at no cost to you. Learn More
Pre-workout is one of the most frequently used supplements by people who work out. However, a question that we often get is "how long does pre-workout last?".
People want to know the answer to this question so that they can better time when they take their pre-workout so that it lasts long enough to do what it's supposed to do in enhancing their workout.
There's quite a variety of options on the market today that contain various ingredients and dosages. Read on to find out how you can better judge how long your pre-workout will last.
WHAT IS PRE-WORKOUT?
Pre-workout is a fitness supplement that usually comes in powder form that's used to increase the intensity of your workout by waking up your nervous system, boosting energy levels, and giving you a bigger pump in the gym. Pre-workouts are generally consumed 30 minutes to1 hour before your workout; that way, the effects will kick off as your training begins.
Each brand will use different ingredients and dosages to enhance performance, but they aren't all equal. So, you'll need to carefully look at the list of ingredients and the amounts to determine whether or not a pre-workout is worth its salt.
Pre-workout comes in two main types: Stimulant or Stimulant-Free.
This will play a role in determining how long a certain pre-workout will last. Aside from stimulants, other performance-enhancing substances in pre-workouts help boost endurance and increase mental focus. Plus, nitric oxide boosters that vasodilate your arteries and veins so that more blood is pumped to your muscles, giving you a pumped-up look while you work out.
The most common stimulant used in pre-workouts is caffeine. There are multiple sources of caffeine generally used in pre-workouts, but it can range from regular caffeine, caffeine from natural sources, caffeine anhydrous, theobromine, and more. We will get into this in the next section because the amount of caffeine and its source will play a role in how long the pre-workout supplement is going to last.
Typical performance-enhancing substances used in pre-workouts are beta-alanine, agmatine sulfate, betaine, creatine, citrulline, malic acid, L-arginine, taurine, sodium bicarbonate, theanine, tyrosine, just to name a few.
With that out of the way, we can get to the nitty-gritty of how long pre-workouts last, and we're not talking about the shelf-life in this context.
HOW LONG DOES IT TAKE FOR PRE-WORKOUT TO KICK IN?
The timing of when you take a pre-workout can influence how long it lasts and how effective it is for your workout. The driving force for using pre-workouts is to help improve your performance for a given training session. Most ingredients in the popular pre-workouts will hit you within an hour, but it could be as short as 20 minutes, depending on your body and the ingredients used. If you train in a fasted state and take pre-workout on an empty stomach, you may start to feel its effects in as little as 15 minutes. It's best to look at the label for guidance on when you should take your pre-workout. Just remember to account for the time it will take you to get to the gym, plus any warm-up that you usually do. Not sure if you've been there before, but once an intense pre-workout starts to kick in and you're not hitting the iron, things can get weird quickly.
HOW LONG DO THE EFFECTS OF PRE-WORKOUT LAST AFTER TAKING IT?
There's no one size fits all to answer this question of how long you'll feel the effects of a pre-workout. To give a ballpark average, many pre-workouts will last from 2-4 hours after ingesting them. This window of time should cover the majority of workouts, especially if they are gym-focused around strength or hypertrophy.
Let's have a look at some factors that influence the amount of time a pre-workout will last in your system.
1. Your age, weight, muscle mass, and fat percentage:
Your situation can influence the length of time a pre-workout will affect your body. Bigger people tend to withstand higher doses of most things, pre-workout included. If you're a small person with little to no fat, a pre-workout could hit you in a more profound way than someone bigger and stronger. Another point to emphasize is age. Older people may have developed a tolerance to caffeine on the one hand, but on the other hand, they also may have other medical conditions that can change how long a pre-workout lasts. Younger people on the opposite end of the spectrum might not have a built-up tolerance to caffeine, so a pre-workout supplement could last longer.
2. Ingredients and dosages used in the pre-workout:
Perhaps the most important guiding factor that dictates how long the pre-workout lasts is what the ingredients are and how much of them are being used. The substances that you're likely to feel the effects from the most are the stimulant used. The most common stimulant used is caffeine. Caffeine is usually absorbed within an hour after ingestion.
Related: What You Need To Know About Pre-workout Ingredients
Let's look deeper at caffeine and how long it can affect your body…
This study says that the mean half-life of caffeine in healthy people is around 5 hours. Researchers, however, say that the elimination half-life can range between 1.5 and 9.5 hours. The window of time that caffeine can affect a person is dependent on multiple factors, including physiological and environmental characteristics. Obesity, pregnancy, altitude, and smoking are a few factors that can influence the effect of caffeine on individuals. In addition, people can build up a tolerance to caffeine with frequent usage, which also plays a part in how long your pre-workout will last.
3. How long and how often you've been taking pre-workout:
If you consistently take the same pre-workout over a long period of time, the effects will dissipate as your body builds up the tolerance to it. To avoid building a tolerance to your pre-workout, you can lower the frequency you're using it or take a week off from taking it after every 4 weeks on.
4. How your body metabolizes caffeine:
Briefly mentioned above, your tolerance will increase over time if you frequently consume caffeine. This plays out in every day society, as we're sure you know someone or even might be that someone who drinks multiple cups of coffee without getting that energy boost. Compare this to someone who doesn't consume coffee often and drinks a small latte after lunch then can't get to sleep that night because their body isn't used to the caffeine. If your body can't handle much caffeine, you're better off sticking with stim-free pre-workout.
5. Daily water intake:
The amount of water you ingest daily can play a part in shortening the time that pre-workout affects your body. If you stay properly hydrated and work out with intensity, you might slightly change the length of time you feel the effects of the pre-workout.
6. Quantity Consumed:
You shouldn't exceed the recommended dosages on the label; it's there for a reason. Sometimes people buy a pre-workout and don't bother to look at the recommended dosing; this can be a big mistake, especially if the product is a high stim pre-workout. It would be best if you always started any pre-workout by taking half the recommended dosage the first time to see how your body reacts before you start taking the full dosage. On the other hand, if you've been using the same pre-workout for a prolonged time and the effects begin to lessen, don't try to compensate by increasing the dosage past the recommended amount.
7. How You Feel Before Consumption:
The length of time a pre-workout lasts can be skewed by your current energy levels. For example, if you had a bad night's sleep and then a taxing day before taking your pre-workout, the effects might wear off quicker than when well-rested.
DOES PRE-WORKOUT EXPIRE (SHELF-LIFE)?
In a different context, the question of how long does a pre-workout last refers to the shelf-life of the product once it's opened. If the tub isn't opened, there should be a date on the package that shows the best-used date. Each pre-workout supplement might vary in terms of how long it will last once opened. If you open a pre-workout and don't finish it within a couple of months, you're likely to see it start clumping up and/or becoming hard.
Here are a few things to look for to tell you whether or not you should continue taking your pre-workout or not:
- Clumpy: If you open the container and the powder inside looks like it has formed a bunch of clumps, then it's likely that some moisture got into the bottle. Generally speaking, it should still be safe to consume and still be effective.
- Smells Off: If your pre-workout doesn't pass a smell test, then it's probably time to toss it in the trash as it may be off.
- Mold: If you spot any signs of mold, then you should throw it away.
- Past Expiration: Better be safe than sorry and throw it away.
How Long Does Pre-Workout Last After Being Mixed in Water?
Another common question people have that we want to answer is in regards to how long pre-workout stays good for once it has been mixed in water and does it lose its effectiveness if waiting to long to drink it once its been mixed...
While there are no clear studies on this, it is generally accepted that pre-workout won't lose its effectiveness if sitting in water (within a reasonable timeframe) and it can be stored in a refrigerator for up to 24 hours (although even a little longer is probably fine too) after being mixed in water.
So, if you wanted to mix your pre-workout in water the night before or you forget to drink it and save it for the next day, it's ok and the effect should be the same. It won't hurt you, that's for sure, so it's worth giving it a try rather than wasting your pre-workout (as long as it has been stored in a fridge). If it has been sitting out in the heat for more than several hours, while probably not a big deal, it's also probably not worth drinking. After all, one scoop of pre-workout doesn't cost that much.
BENEFITS OF PRE-WORKOUT:
Pre-workout supplements offer multiple benefits to improve your training sessions, so you're able to achieve better results.
Let's have a quick look at the benefits of pre-workout and how they relate to the original question of how long they last:
- Energy Boost: This is one of the main reasons people take pre-workout supplements. More energy in the gym can lead to more reps and more overall volume. Pre-workouts are a great way to get a pick me up before a training session. The increased energy levels are largely because of stimulants used in the formulations that primarily come in the form of caffeine. If you're sensitive to caffeine, then look for stim-free pre-workouts that can offer an energy boost through other means.
- Enhanced Focus: Better focus in the gym means fewer distractions, more mind-muscle connection, and hopefully more gains. Mental clarity in the gym is great to keep you on track. Stimulants such as caffeine can help with this as well as Tyrosine, Alpha-GPC, Huperzine A and Taurine.
- Bigger Pumps: Apart from stimulants, energy boosters, or substances to help you focus, pre-workouts almost certainly will include substances to help you achieve bigger pumps in the gym. These bigger pumps can push you to go harder and stimulate new muscle growth. Nitric oxide boosters vasodilate the blood vessels in the body so blood can freely flow to the muscles giving you those skin tearing pumps.
- Improved Performance: This study showed that pre-workout supplements could result in massive improvements in anaerobic peak and mean power values compared with people who didn't ingest one. If you're looking for an edge and have never tried a pre-workout before, it might be worth shelling out $20-40 to see if your workouts can be improved.
This pre-workout features natural and evidence-based ingredients, fully transparent labeling, and absolutely no artificial color, sweetener, or flavoring. Formulated to enhance strength...
SIDE EFFECTS OF PRE-WORKOUT:
Each pre-workout can have different side effects depending on the ingredients and the quantity used. We covered the benefits of pre-workout, which far outweigh the adverse side effects for many; that's why pre-workout continues to be one of the most popular fitness supplements on the market.
Here are some feelings and side effects that common ingredients in pre-workout may produce.
Of course, everyone will experience the impact slightly differently based on some of the factors we covered above.
- Tingling/Itchy Skin: One of the most common substances used in pre-workout supplements is beta-alanine. Beta-alanine is a performance-enhancing non-essential amino acid that has shown promise in boosting performance in some high-intensity activities that last at least 60 seconds up to a few minutes. It's important to note that this is a saturation ingredient that only provides the benefits once the body has loaded up a certain threshold which means you'd have to take an effective dosage for days on end before. This substance is the prime culprit when it comes to that tingling sensation you get after taking a pre-workout. This tingling or itchy skin feeling called paresthesia isn't harmful. Some people love this sensation because they can feel the effects while others can't stand it. Paresthesia usually lasts up to 30 minutes then tends to lessen with time. If you hate this feeling, you can get pre-workout without beta alanine and we promise it's just as effective for energy, pump, and focus, there's just no itch.
- Anxiousness/Restlessness: The leading cause of these feelings is usually the result of caffeine intake. Many pre-workouts use caffeine anhydrous as a stimulant, a dehydrated, pure form of caffeine. If you consider a regular cup of coffee can contain 80-100 mg of caffeine, then you'll understand how a pre-workout with 300-400 mg of caffeine can hit you pretty hard. Make sure that you can time your workout correctly, so you don't end up taking a powerful pre-workout then not do anything to release the heightened energy from the caffeine intake. You can look for a pre-workout with lower levels of stimulants or even stim-free if you are sensitive to caffeine. Learn more about how much caffeine is ideal for pre-workout.
- Red/Itchy Skin: If your pre-workout doesn't have beta-alanine and you still experience some itchiness or red skin, it is usually related to niacin or possible nitric oxide boosters. This is another effect that comes down to individual experience and preference. Some like this effect to know the pre-workout is working while others dislike it. Once again, start off small when using a new pre-workout to see how your body reacts before taking a full dose.
- Stomach Discomfort: Substances used in pre-workouts can lead to upset stomachs, discomfort, and even diarrhea. For example, sodium bicarbonate, AKA baking soda, is used in some products and can lead to stomach discomfort in some people. In addition, the high amount of caffeine is usually responsible for making people want to poop after taking pre-workouts. Also, if your supplement has expired, causing your pre workout to go bad, it may further worsen your stomach issues.
- Inability to Sleep: Once again, caffeine is usually the reason for this side effect. Most pre-workouts with stimulants will state on the label that you shouldn't take it within 4 hours of your bedtime. Insomnia can be a real pain in the neck for some people if they don't metabolize caffeine well. This should drive home the point that you should always start with smaller doses of pre-workout the first few times you take it until you know how your body will react.
Related: The Pros and Cons of Pre-Workout
TIPS ON TAKING PRE-WORKOUT:
Follow some of these tips to ensure you get the most out of whatever pre-workout you take.
- Timing is Key: Try to consume the pre-workout within 45 minutes of exercising. Don't forget about travel time to the gym, changing, visiting the restroom, how long your workout should be, checking into the gym, and warming up.
- Don't Use Pre-workout As A Crutch: Most people who use pre-workout do so to have a better or more productive training session. Whether you're training for hypertrophy, strength, power, or endurance, you shouldn't NEED pre-workout EVERY time you work out. Pre-workouts are best used to supplement your training. We usually advise you don't take pre-workout more than 5 times a week. Although pre-workout is generally deemed a safe supplement, it's important not to overdo it. Don't let it get to a point where you can't work out without it. Instead, focus on improving your diet, lifestyle, and sleep, which can all lead to performance enhancement.
- Check The Label: Every brand will use its own formulations when creating a pre-workout. Therefore, it's vital to know what's in your pre-workout and the corresponding dosage so you can understand the possible effects they will have on you and how long they'll last. Look for key ingredients, like GlycerPump, that will help you get the most out of your workouts. Also, stay away from brands that use proprietary labels for the most part, as this is how manufacturers can fluff the effectiveness of their products while cutting costs.
- Don't Overdo It: Manufacturers display a label with the recommended serving size related to the ingredients and doses used. They set these serving sizes for a reason; they understand the potential effects it can have on people, and they want to avoid situations where there might be some health concerns. Believe us, many companies would like to set larger serving sizes so that you would need to replenish your product in a shorter amount of time. Stay within their recommended guidelines!
- Buy From Reputable Brand: The supplement industry is rife with people trying to take advantage by offering sub-par products with big marketing claims. So, try to do your homework or check out our roundup of the best pre-workouts; we saved you the time and effort of looking into hundreds of options online.
- Avoid Proprietary Blends: You should avoid most pre-workouts that include proprietary blends of the main active ingredients. It's best to know precisely what substances are used and how much of each of them you are taking. Pre-workouts should contain science-backed ingredients that are formulated with efficacious doses. All too often, we see what might look like a decent pre-workout on the surface fall short wherein it comes to how much of each substance is in one serving.
- Don't Combine With Coffee: If you're making a pre-workout that has a stimulant, most likely in the form of caffeine, then there's no need to consume more in the form of a coffee. The FDA recommends that daily caffeine intake doesn't exceed 400mg. Although some pre-workout supplements will contain 300-400 mg, be careful of your total caffeine intake as it can lead to adverse health effects.
- Look For Third-Party Tested Pre-Workouts: Look for brands that offer products tested by third parties. By having a third-party test the pre-workout supplement, you can put your mind at ease a bit because you can expect to get a pure product that isn't tainted. Some larger supplement companies in the recent past have used illegal substances in products. This issue of shady business practices isn't going anywhere anytime soon.
FINAL THOUGHTS:
You can assume that most mainstream pre-workout supplements will last for at least 2 hours after taking it, with possible lingering effects to last up to 6 hours or more depending on a multitude of factors we covered above. The key takeaway from this post is that pre-workouts can affect everyone slightly differently. To avoid adverse side effects of pre-workouts, make sure you start small with a half dosage before going all-in on a full dosage. Then, you can work your way up to a full dose so that your body has time to adjust to it.
- 14 Best Pre-Workouts on the Market
- 9 Best Caffeine-Free Pre-Workouts
- 3 Easy Homemade Pre-Workout Recipes
More frequently asked questions about pre-workout:
Garett Reid
Author