Some links in this article are affiliate links, which means we earn from qualifying purchases. Learn more.
Pre-workout supplements are popular and effective in increasing exercise performance, but with so many different ingredients you might be wondering if any of them have possible side effects, like weight gain.
So, does pre-workout cause weight gain? Your pre-workout may cause weight gain, but this isn’t necessarily correlated to fat gain. Any weight gain from pre-workout is likely related to increases in water weight from creatine monohydrate, or increased muscle mass from training.
If your current sport or training goal involves maintaining or reaching a particular weight, it’s important to know which ingredients could be contributing to weight gain so that you don’t purchase products that work against your goals.
- Most of the ingredients found in pre-workout will not cause weight gain but there are a few to watch out for.
- Creatine monohydrate may cause short-term weight gain (1-2% of your body weight) as water stored within the muscle cells.
- If you consume too many stimulants in your day (pre-workout, coffee, energy drinks, soda, etc), and have unmanaged stress, your cortisol levels could be elevated resulting in increased fat storage.
What Is Pre-Workout?
Pre-workout supplements contain ingredients that provide short-term (1-2 hour) performance enhancements. This includes increased energy, mental focus, strength, power, or endurance.
There are a wide range of pre workout options available. Some blends are heavily focused on stimulants and ingredients that encourage mental focus, whereas other options are caffeine-free and contain ingredients to increase strength and blood flow.
Ultimately, whether your pre-workout contributes to weight gain will be dependent on the blend and dosage of key ingredients.
Common Pre-Workout Ingredients
Though each company will have its own unique formulation, most of the ingredients found in pre-workouts are similar because supplement companies want to use the most effective ingredients.
- Caffeine: used to increase energy in the short term
- Creatine: increases strength, power output, and muscle mass
- Beta-Alanine: improves endurance and increases time to exhaustion
- Nitric Oxide Precursors (arginine, citrulline): enhances blood flow and increases time to exhaustion
- Taurine: may prevent oxidative stress and increase mental focus and feelings of calm
- Betaine: may increase strength and power and improve body composition
Pre-Workout & Weight Gain
Pre-workouts can cause weight gain but it’s very unlikely that your pre-workout would cause significant weight gain because these supplements are typically low calorie (0-10 calories/serving) and contain ingredients that increase energy expenditure and/or calorie burning.
Weight gain that occurs from pre-workout is likely related to increases in fat-free mass (muscle weight, water weight, etc.) but there is also a chance that it could cause increases in fat mass as well, which I’ll explain below.
The two main ingredients responsible for slight weight gain are creatine and stimulants.
One possible culprit contributing to weight gain is creatine monohydrate, which can cause an increase in body weight by 1-2% due to water retention within the muscles.
For example, a 150lb individual could gain approximately 1.5 to 3 pounds of water in their muscles while taking creatine.
Significant water retention is more likely to occur when you follow a loading phase protocol, where you take up to 25g of creatine each day (5x the daily maintenance dose), to saturate the body’s creatine levels more quickly.
Most pre-workout supplements only contain 1-5g of creatine per serving, which is too low to cause large amounts of water retention, especially if you aren’t taking your pre-workout every single day.
The most probable reason that you would gain weight from creatine in your pre-workout supplement is that you built more muscle mass due to its ability to encourage strength and muscle gain.
Stimulants: The Caffeine, Stress, and Cortisol Connection
An excess of caffeine or stimulants could also contribute to a small amount of weight gain.
This may sound counterintuitive, because most fat-burning products do contain caffeine and/or stimulants, but the key here is the quantity of these ingredients and your overall stress management.
First, let’s discuss cortisol.
Cortisol is the body’s main stress hormone, and increased cortisol levels have been shown to be a positive predictor for weight gain. Physical and psychological stress can both increase cortisol levels in the body.
Caffeine and stress can also increase cortisol secretion. So, if you are under chronic stress (emotional stress, work/school stress), you workout intensely, and you consume caffeinated beverages, you could be setting yourself up for a trifecta of high cortisol-secreting behaviors.
When cortisol levels stay elevated for an extended period of time, you can experience side effects like anxiety, difficulty sleeping, and weight gain.
Weight gain occurs because high levels of cortisol negatively impact your hunger cues, causing you to eat more than you typically would.
Ultimately, the amount of caffeine in your pre-workout probably isn’t enough to cause significant weight gain. But when your pre-workout is combined with other stimulants throughout the day (coffee, energy drinks) and a high-stress environment, the combination could contribute to some weight gain.
Artificial sweeteners also get an honorable mention because they are known to cause digestive issues in many individuals. If you’re consuming pre-workout regularly and you’re experiencing digestive issues like bloating, then your weight may be increasing even though you’re not gaining fat.
It is also important to note that it was previously thought that using artificial sweeteners could cause fat gain by encouraging overeating, but the most recent research since 2022 debunks that.
Key Takeaway: Your pre-workout is unlikely to cause you to gain body fat. You may notice a slight increase in body water weight from creatine monohydrate supplementation, but as long as you are staying within a healthy and reasonable caffeine limit (at or below 400mg daily) and are managing overall stress and anxiety, then weight gain shouldn’t be a concern.
Avoiding Weight Gain When Taking Pre-Workout
Find One Without Creatine
If you want to avoid the possibility of water retention due to creatine intake, find a pre-workout that doesn’t contain creatine.
At the time this article is being written, creatine monohydrate is really expensive due to a break in the supply chain, so a lot of companies are pulling creatine out of their products. This makes it more likely that you will find a lot of pre-workout options without creatine.
A product like Ghost Legend Pre-Workout has a reasonable caffeine level (250mg) and no creatine or glycerol meaning it can provide good energy and mental focus with a reduced likelihood of negative side effects.
Alternatively, different types of creatine like creatine HCL are said to provide the performance benefits of creatine monohydrate without water retention. Finding a formula (like PreJym Pre-Workout) that uses creatine HCL could mitigate the water weight.
Manage Stress And Caffeine Intake
It is likely that caffeine is safe in doses below 400mg daily. The effects of caffeine will vary from person to person, so it might be worth considering a pre-workout that is low in caffeine or caffeine-free, like Axe&Sledge Hydraulic.
Make sure to stay in control of your total overall daily stress by engaging in stress-reducing behaviors like yoga or meditation, and keeping a manageable workload.
I also recommend prioritizing your sleep by aiming to get 7-8 hours per night. To improve your sleep quantity and quality you can reduce screen time before bed (from phones/ laptops/ tv/ tablets), and limit caffeine within 5 hours of your desired bedtime.
Be Mindful Of Your Calorie Balance
A positive energy balance (consuming more calories than you are burning) will result in weight gain. A negative energy balance (burning more calories than you consume) will result in weight loss.
While it’s unnecessary to track every macronutrient or calorie for the rest of your life to be healthy, taking a week to check in every couple of months can be beneficial.
Small habits can start to creep into your routine without you even noticing. Habits like mindless snacking and increasing portion sizes can cause a positive calorie balance and result in weight gain.
Other Side Effects of Pre-Workout
Pre-workout supplementation also has other common side effects, such as:
Because pre-workouts contain ingredients like stimulants which can increase energy, workout intensity, and overall energy expenditure, weight loss is a possible side effect of taking pre-workout.
Some pre-workouts also contain thermogenic ingredients (ingredients that increase core temperature) and can result in increased sweating and increased calorie expenditure.
Ultimately, whether you lose or gain weight while taking pre-workout depends on your total calorie intake but pre-workout can assist in weight loss by increasing energy expenditure as long as your cortisol levels aren’t too high and affecting your hunger cues.
Pre-workout supplements can also cause side effects like a racing heart, anxiety, jitteriness, or insomnia (especially if taken within 5 hours of going to bed). These symptoms are a result of a higher amount of caffeine and stimulants in pre-workout.
If you’re someone who is sensitive to caffeine and other stimulants or is prone to anxiety then I recommend choosing a non-stim pre-workout like Beyond Yourself Superset Stim-Free.
Lastly, pre-workouts have also been known to cause nausea. There are a few reasons why your pre-workout may cause nausea. One reason is that certain ingredients in pre-workout can cause digestive upset; these ingredients include caffeine, creatine monohydrate, and glycerol.
Some other potential reasons why your creatine makes you nauseous include having too much caffeine in your day, taking more than the recommended dose, and using too much or too little water when mixing your pre-workout.
Other Pre-Workout Resources
- Pre-Workout Makes Me Pee (Causes & Fixes Explained)
- Creatine vs Pre-Workout: Differences, Pros, Cons
About The Author
Jennifer Vibert is a Certified Strength and Conditioning Specialist, Nutrition Coach, and supplement store manager. She has a Bachelor of Kinesiology with a major in Fitness and Lifestyle and a minor in Psychology from the University of Regina. She is a Certified Nutrition Coach through Precision Nutrition, with a passion for helping clients learn the fundamentals of nutrition and supplementation in order to build healthy, sustainable habits.