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To optimize the timing of pre-workout for both your gym sesh and your sleep time, you need to know how long the pre-workout will stay in your system.
Pre-workout can stay in your system for six or more hours, but the peak effects are felt within 30-90 minutes. The length of time pre-workout stays in your system depend on the dosage, the ingredients, as well as personal factors like your body size, body composition, and activity level.
To help you get the most out of your pre-workout without compromising your sleep & recovery, I’ll explain how you can optimize your pre-workout intake in terms of both the size and timing of your dose.
- The pre-workout ingredients that you are most likely to “feel” are caffeine and beta-alanine.
- The length of time pre-workout stays in your system is also influenced by your nutrition, as consuming it with food and beverages can slow its rate of digestion and absorption.
- There are different types of pre-workout products to choose from depending on how long you want the effects to last.
What Is Pre-Workout?
The term “pre-workout” usually refers to a multi-ingredient blend of supplements that have been studied to enhance exercise performance by boosting energy levels, improving mental focus, and/or increasing blood flow to working muscles.
The ingredients present in a blend of pre-workout will determine which performance-enhancing effects it has to offer.
Some of these blends contain nervous system stimulants like caffeine to increase mental focus, along with ergogenic ingredients (substances that are intended to enhance physical performance, stamina, or recovery) like creatine.
Other products specifically exclude stimulants (“stim-free”), and only have performance-promoting compounds like specific amino acids, making them a better choice for teenagers, or people who are sensitive to stimulants or find them disruptive to their sleep.
How Long Do The Effects Of Pre-Workout Last?
In general, the effects of pre-workout last 1-2 hours, but this depends on the specific blend of ingredients in your pre-workout formulation, as well as the amount and type of each ingredient. Many ingredients will also remain in your body for several hours after you stop feeling their effects.
If you want to time your ingestion of pre-workout so that you feel its effects when you need them most, then you’ll want to know how long it takes to reach peak concentration levels.
However, if you’re more concerned with how long it will stay in your system, then you’ll need to know its half-life.
Take caffeine for example, which is a common pre-workout ingredient that increases alertness, focus, and energy.
There are two common types of caffeine used in pre-workout: caffeine anhydrous, which reaches peak concentration within 1-2 hours, and di-caffeine malate, which can take 2-3 hours to reach peak levels.
However, the half-life of caffeine (the amount of time it takes for levels in your body to drop by half) is 2.5 to 7 hours.
Most people “feel” caffeine because it stimulates the release of the “feel good” neurotransmitter dopamine, leading to a sense of happiness or even euphoria; but many people don’t realize that caffeine stays in your system even after these feelings of euphoria dissipate.
The presence of caffeine in your system, even after the initial feelings of alertness and euphoria have dissipated, can have several effects.
- Sleep Disruption: Caffeine can interfere with your sleep cycle. This can lead to sleep deprivation and associated issues like fatigue, poor concentration, and mood changes.
- Increased Heart Rate and Blood Pressure: Caffeine can cause an increase in heart rate and blood pressure, which may not be noticeable but can be problematic for people with high blood pressure.
- Dehydration: Caffeine is a diuretic, meaning it can cause your body to lose water. This can lead to dehydration if you’re not replenishing your body’s water supply.
Another common pre-workout ingredient is beta-alanine, which helps delay the onset of muscle fatigue.
It is also the ingredient in pre-workout that causes sensations like paresthesia, or skin tingling.
Beta-alanine, compared with caffeine, reaches peak concentration much quicker; about 30-40 minutes, with a half-life of about 1 hour.
In this study, beta-alanine was undetectable after 3 hours, suggesting that it leaves your system much faster than caffeine, too.
The quick dissipation of beta-alanine from your system means that:
- Side effects are short-lived: For those that don’t like skin tingling, this experience won’t last long.
- You have to dose more frequently: Because beta-alanine leaves the system quickly, to maintain its performance-enhancing effects, it may need to be taken more frequently, especially on workout days. This could be inconvenient for some people.
There are fewer studies on peak concentration times and half-lives of other common pre-workout ingredients, largely because they do not produce noticeable physical sensations.
Since the timing of when you will feel the peak effects of pre-workout can vary greatly from person to person (more on this next), my recommendation is to experiment with different timing, from 0-60 minutes before your workout, to see what feels best for you.
- Related Article: What Does Pre-Workout Feel Like? 7 Things You’ll Feel
Seven Factors That Determine How Long Pre-Workout Stays In Your System
The seven factors that determine how long pre-workouts stay with you are:
1. The Amount of Each Ingredient Per Serving
The more ingredients a pre-workout has, the longer that pre-workout will stay in your system.
This is because the more ingredients there are, the longer it’s going to take your body to use up those ingredients, meaning it will stay in your system for longer periods.
For the exact same reasons, the amount of each ingredient will also determine how long a pre-workout will stay in your body.
For example, if your pre-workout has 400 mg of caffeine anhydrous per serving, there will still be about 200 mg in your system 3-4 hours later.
But, if your pre-workout has only 200 mg of caffeine anhydrous, then there will be only 100 mg of caffeine in your system 3-4 hours later.
2. The Number of Servings
Similar to the amount of each ingredient per serving, if you take multiple servings in a day, either at the same time or within 3 hours of each other (before the first dose has “worn off”), pre-workout will stay in your system for longer.
For example, if you take 1 serving of pre-workout with 200 mg of caffeine, it could take 6 hours before it is out of your system; if you take 2 servings of the same pre-workout, it could take 12 hours before it is out of your system.
This can make a big difference if you train in the afternoon and your bedtime is only 6 hours (or fewer) away from your training time.
Keep in mind that you should only take pre-workout twice in one day if you have two intense training sessions that day.
If you are taking more than one serving per day, you should ensure you do not surpass 400 mg of caffeine per day (the upper limit for caffeine intake).
3. Your Body Mass
Studies on caffeine for boosting performance generally base recommended intake in terms of body weight, suggesting at least 3 mg of caffeine per kg of body weight.
Beyond just caffeine, people with higher body mass generally have a higher baseline metabolic rate (they burn calories at a faster rate) than people with lower body mass, meaning pre-workout would stay longer in your system if you have a lower body mass.
4. Your Body Composition
Beyond just body mass, body composition also plays a role in how long pre-workout stays in your system because leaner people have a higher metabolic rate (burn more calories per day) than people with a higher body fat percentage even if they weigh the same.
5. Your Activity Level
The more active you are, the higher your energy expenditure, meaning the more quickly your body will use up all ingested nutrients, whether from whole foods or from supplements like pre-workout.
If you are highly active, pre-workout will not stay as long in your system as people who are less active.
6. Your Sensitivity To Caffeine
Beyond metabolism in general, there are genetic differences in how certain people metabolize caffeine in particular.
People with the CC genotype metabolize caffeine very slowly, whereas people without this genotype metabolize caffeine quickly and feel its effects right away.
This slow metabolism of caffeine means it will stay in your system longer if you have the CC genotype, but you are less likely to experience a surge of energy from the caffeine because it’s being released slowly into your body.
7. Taken With Or Without Food
Taking a pre-workout on an empty stomach is also going to make a difference compared to taking a pre-workout with food.
If you take pre-workout with food, it can stay in your system for longer periods because it will be metabolized along with the food that you’ve eaten.
Fat and fiber are the slowest-digesting nutrients so consuming pre-workout with foods containing these nutrients will prolong the length of time it stays in your system.
If you want to pre-workout to leave your system more quickly, then it’s best to take it on its own.
- Related Article: Why Does Pre-Workout Not Affect Me?
Longer-Lasting Energy: Pre-Workout Products
If you want a pre-workout supplement that is going to keep you going, and going, I recommend looking for a product that contains multiple forms of caffeine (both caffeine anhydrous and di-caffeine malate), to benefit from the different half-lives of these two forms, as well as other performance-boosting ingredients.
Pro Supps Mr. Hyde Xtreme Pre-Workout gets full marks for my criteria because it has:
- 300 mg of caffeine anhydrous
- 70 mg of di-caffeine malate
- 50 mg of caffeine citric acid blend
- 2.5 g of beta alanine
- 500 mg of L-citrulline aspartate
- 250 mg of creatine HCI
This is a great choice if your workout will last longer than 1-2 hours, and/or if you have a high body mass (>140 kg) or are very lean (<10% body fat).
Be mindful that this product has 420 mg in total of various forms of caffeine, which is just over the recommended daily limit of 400 mg of caffeine.
I recommend starting with a smaller dose (half a scoop) to see how you tolerate the product and to avoid any other caffeinated products (like chocolate, tea, or coffee) during the day.
Short-Lived Energy: Pre-Workout Products
For a shorter-lasting energy boost, I’d look for a product that only has caffeine anhydrous for caffeine and also contains a high dose of beta-alanine.
I recommend Staunch Koala Freak 2.0 Pre-Workout because it has:
- 360 mg of caffeine anhydrous
- 3 g of beta-alanine
- 6 g of citrulline malate
- A B-vitamin blend (B vitamins are helpful for energy metabolism)
This is perfect for intense workouts up to 90 minutes in length, for individuals weighing up to 120 kg (264 lbs).
If you are a smaller person (up to 60 kg/132 lbs), start with a half serving and only increase if needed.
Ways to Get Pre-Workout Out Of Your System More Quickly
If you’re set on taking pre-workout in the afternoon or evening, but you don’t want it to affect your sleep then here are some tips to help get it out of your system.
Choose A Stimulant-Free Pre-Workout
If you’re worried about having stimulants in pre-workout, and getting them out of your system quickly so that they don’t impact your sleep, then the easiest solution is to choose a stim-free pre-workout.
My favorite stimulant-free pre-workout is Transparent Labs Stim-Free Pre-Workout because it has ingredients like L-Tyrosine that promote focus and other ingredients that help to delay fatigue and promote and improve muscular strength and endurance.
- Related Article: 9 Pre Workout Alternatives That Won’t Make You Crash
Take A Smaller Dose
The easiest and most obvious way to get pre-workout out of your system more quickly is to take a smaller dose, to begin with, so there is a smaller amount of ingredients for your body to use up.
I recommend starting with a half or even quarter dose of pre-workout to see how it makes you feel.
If you’re able to tolerate it and clear it from your system fast enough that it doesn’t affect your sleep, then you could try building up to a larger dose over the course of 2-4 weeks or just stick to the smaller dose.
Drink More Water
Pre-workout might already make you pee more; this is because of the diuretic effect of caffeine as well as the fact that creatine can make you thirsty by drawing water into your cells – when you drink more, you pee more.
You can take advantage of this increased urination by drinking even MORE water because the more often you pee, the more quickly you are flushing pre-workout out of your system.
The only downside to this method for clearing it out of your system so that you can sleep is that your sleep will still be affected if you’re getting up throughout the night to go to the bathroom.
Workout Longer Or Harder
Finally, since higher activity levels increase the rate at which you burn through ALL intake, working out longer and/or harder will also increase the rate at which you use up the pre-workout in your system.
This can benefit your sleep because the more tired you are from your workout, the more likely you are to sleep (assuming you’re giving yourself time to wind down after your workout).
However, it’s important to support these more intense workouts with adequate recovery and nutrition so that you don’t increase your risk of illness or injury.
Frequently Asked Questions
How does the type of exercise I’m doing impact how long pre-workout stays in my system?
The type of exercise you’re doing can influence how quickly your body metabolizes the ingredients in your pre-workout supplement. High-intensity exercises like weightlifting or sprinting can cause your body to use up the ingredients faster due to increased energy expenditure.
On the other hand, lower-intensity exercises like steady-state cardio may not use up the ingredients as quickly.
Therefore, if you’re doing high-intensity workouts, you might find that the effects of pre-workout supplements wear off faster compared to lower-intensity workouts.
What are the potential interactions between pre-workout supplements and other medications or supplements I might be taking?
Pre-workout supplements can interact with other medications or supplements. For instance, if you’re taking medication for high blood pressure, the stimulants in pre-workout supplements could potentially increase your blood pressure further.
Similarly, if you’re taking other supplements that contain caffeine, combining these with a pre-workout could lead to excessive caffeine intake.
It’s important to consult with a healthcare provider before starting a pre-workout supplement, especially if you’re taking other medications or supplements.
How does the frequency of my workouts impact how long pre-workout stays in my system?
If you’re working out daily, your body may metabolize pre-workout supplements more quickly due to the consistent demand for energy. This could potentially shorten the duration that pre-workout stays in your system.
Conversely, if you’re working out less frequently (e.g., every other day or a few times a week), the pre-workout might stay in your system longer as your body doesn’t have the same consistent demand for energy.
However, individual metabolic rates can vary, so it’s always important to monitor how your own body responds.
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About The Author
Lauren Graham is a Precision Nutrition Level 1 certified nutrition coach. She focuses on helping busy professionals balance healthy eating and purposeful movement. Lauren has a background in competitive swimming and is currently competing as a CrossFit athlete. She has a passion for training, teaching, and writing.
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