“Does pre-workout make you poop?”
This may seem like a silly question, but it’s one many people ponder.
Why do you feel the need to use the bathroom after taking pre-workout?
What other factors contribute to pre-workout-induced pooping?
And how can you choose a pre-workout that boosts your performance without making you rush to the restroom?
Get evidence-based answers to these questions and more in this article.
Table of Contents
A “pre-workout” is a sports nutrition supplement taken before training to enhance energy levels and exercise performance.
You don't need supplements to build muscle, lose fat, and get healthy. But the right ones can help. Take this quiz to learn which ones are best for you.
Find the Perfect Supplements for You in Just 60 Seconds
You don't need supplements to build muscle, lose fat, and get healthy. But the right ones can help. Take this quiz to learn which ones are best for you.Take the Quiz
Many pre-workout powders contain ingredients that interact with your digestive system and stimulate bowel movements.
Common pre-workout ingredients with this side effect are sodium bicarbonate, vitamin C, magnesium, caffeine, and artificial sweeteners.
Caffeine is probably the most common pre-workout ingredient. In some cases, supplements contain as much as 600 mg of caffeine (more than 6 times the caffeine content of a cup of caffeinated coffee).
Caffeine is a pre-workout mainstay because it boosts athletic performance by improving strength, promoting muscle endurance, and enhancing anaerobic performance. However, it also impacts your digestive system.
Specifically, caffeine stimulates colonic motor activity—the process of moving your gut’s contents through the digestive tract. In other words, it gets your colon rollin’.
Many pre-workout supplements contain large amounts of artificial sweeteners.
Magnesium plays a crucial role in muscle function and energy metabolism and is, therefore, a common ingredient in pre-workout formulas.
Beware though, high doses can draw water into your intestines, speeding up digestion and potentially leading to untimely restroom trips.
Supplement companies sometimes include vitamin C in pre-workout powders as a flavoring and to potentially accelerate post-exercise recovery by reducing inflammation (which may also blunt some of exercise’s positive effects).
The downside is that taking large doses can upset your stomach.
That said, most pre-workouts don’t contain enough vitamin C to cause this effect alone. Thus, it’s only a concern if you also consume a diet rich in vitamin C.
Some people take sodium bicarbonate (baking soda) as a “homemade” pre-workout because it may boost athletic performance.
However, baking soda also causes a buildup of CO2 in the stomach, which commonly causes diarrhea.
How many calories should you eat? What about "macros?" What foods should you eat? Take our 60-second quiz to get science-based answers to these questions and more.
Find the Best Diet for You in Just 60 Seconds
How many calories should you eat? What about "macros?" What foods should you eat? Take our 60-second quiz to get science-based answers to these questions and more.Take the Quiz
The timing of your pre-workout intake greatly influences its effect on your digestion.
For instance, if you consume pre-workout in the morning when your stomach is empty, your body will absorb the ingredients rapidly. This may increase the odds you’ll need to use the bathroom.
If you take pre-workout before an afternoon or evening workout, you’re less likely to experience digestive issues. That’s because the food you’ve eaten throughout the day prevents your body from absorbing the pre-workout as quickly.
Ingredients like caffeine and artificial sweeteners have a “dose-dependent impact” on your body.
In other words, the more you consume, the higher your chances of experiencing side effects.
Therefore, finding products that include doses that maximize benefits without leading to unwanted effects is key.
The contents of your stomach can also influence how pre-workout affects your digestive system.
For instance, taking your supplement with food can slow digestion, potentially reducing any laxative effect.
On the other hand, taking pre-workout powder on an empty stomach can worsen its side effects.
Of all the ingredients above, caffeine is the most likely to cause stomach upset and bowel movements.
Therefore, using a pre-workout that doesn’t contain caffeine can effectively prevent pre-workout-induced pooping.
That’s where “stim-free” pre-workouts come in.
Stim-free pre-workouts are supplements that contain no stimulatory ingredients (e.g. caffeine) but still improve your athletic performance.
This makes them a suitable alternative for those experiencing digestive issues with regular pre-workout powders.
Opting for pre-workout powders that contain natural sweeteners and flavors can help minimize digestive upset.
Generally, natural options are more digestible, potentially leading to fewer stomach problems than artificial alternatives.
Many people wrongly assume that when it comes to pre-workout ingredients, higher doses are better.
This is a misconception—most pre-workout ingredients only boost performance up to a certain point.
Taking more than this doesn’t improve your performance further, but it can increase your risk of experiencing unwanted side effects.
Unfortunately, some supplement companies capitalize on the “more is better” mindset by including excessive doses of stimulants in their products. This makes their products appear more potent, even though they’re actually less effective (and potentially dangerous).
To avoid this trap, look for products containing clinically effective doses of each ingredient.
This means they include each ingredient at a level that confers the maximum benefits with the minimum side effects.
. . . and it's yours for free. Take our 60-second quiz and learn exactly how many calories you should eat, what your "macros" should be, what foods are best for you, and more.
Some Nutritionists Charge Hundreds of Dollars for This Diet "Hack" . . .
. . . and it's yours for free. Take our 60-second quiz and learn exactly how many calories you should eat, what your "macros" should be, what foods are best for you, and more.Take the Quiz
If you want a 100% naturally flavored and sweetened pre-workout supplement containing clinically effective doses of 6 performance-boosting ingredients like caffeine, citrulline malate, and beta-alanine, try Legion’s pre-workout powder, Pulse.
Or, if you’d prefer a 100% natural and stimulant-free pre-workout drink that boosts strength and stamina while reducing fatigue, try stim-free Pulse.
Choosing the right pre-workout supplement can significantly improve your athletic performance and energy levels.
However, it’s crucial to understand the impact ingredients like caffeine and artificial sweeteners have on your digestive system.
To minimize stomach upset, choose a pre-workout containing clinically effective doses of every ingredient. And if you still experience unexpected bowel movements soon after taking your pre-workout, opt for a stim-free version instead.
+ Scientific References
- Guest, Nanci S., et al. “International Society of Sports Nutrition Position Stand: Caffeine and Exercise Performance.” Journal of the International Society of Sports Nutrition, vol. 18, no. 1, 2 Jan. 2021, jissn.biomedcentral.com/articles/10.1186/s12970-020-00383-4, https://doi.org/10.1186/s12970-020-00383-4.
- J. Boekema, M. Samsom, G. P. van Be, P. “Coffee and Gastrointestinal Function: Facts and Fiction: A Review.” Scandinavian Journal of Gastroenterology, vol. 34, no. 230, Jan. 1999, pp. 35–39, https://doi.org/10.1080/003655299750025525. Accessed 25 Nov. 2020.
- Grembecka, Małgorzata. “Sugar Alcohols—Their Role in the Modern World of Sweeteners: A Review.” European Food Research and Technology, vol. 241, no. 1, 28 Feb. 2015, pp. 1–14, https://doi.org/10.1007/s00217-015-2437-7. Accessed 16 Oct. 2019.
- Lenhart, Adrienne, and William D Chey. “A Systematic Review of the Effects of Polyols on Gastrointestinal Health and Irritable Bowel Syndrome.” Advances in Nutrition, vol. 8, no. 4, 6 July 2017, pp. 587–596, www.ncbi.nlm.nih.gov/pmc/articles/PMC5508768/, https://doi.org/10.3945/an.117.015560. Accessed 20 Apr. 2020.
- Zhang, Yijia, et al. “Can Magnesium Enhance Exercise Performance?” Nutrients, vol. 9, no. 9, 28 Aug. 2017, p. 946, www.mdpi.com/2072-6643/9/9/946/htm, https://doi.org/10.3390/nu9090946.
- Bothe, Gordana, et al. “Efficacy and Safety of a Natural Mineral Water Rich in Magnesium and Sulphate for Bowel Function: A Double-Blind, Randomized, Placebo-Controlled Study.” European Journal of Nutrition, vol. 56, no. 2, 18 Nov. 2015, pp. 491–499, https://doi.org/10.1007/s00394-015-1094-8.
- Santos de Lima, Katieli, et al. “Effects of the Combination of Vitamins c and E Supplementation on Oxidative Stress, Inflammation, Muscle Soreness, and Muscle Strength Following Acute Physical Exercise: Meta-Analyses of Randomized Controlled Trials.” Critical Reviews in Food Science and Nutrition, vol. 10.1080/10408398.2022.2048290, no. 10.1080/10408398.2022.2048290, 9 Mar. 2022, pp. 1–14, https://doi.org/10.1080/10408398.2022.2048290. Accessed 28 Mar. 2022.
- Aguiar, Samuel Silva, et al. “Oxidative Stress, Inflammatory Cytokines and Body Composition of Master Athletes: The Interplay.” Experimental Gerontology, vol. 130, no. 130:110806., 1 Feb. 2020, p. 110806, pubmed.ncbi.nlm.nih.gov/31825853/, https://doi.org/10.1016/j.exger.2019.110806. Accessed 31 Dec. 2022.
- Compounds, Institute of Medicine (US) Panel on Dietary Antioxidants and Related. Vitamin C. Www.ncbi.nlm.nih.gov, National Academies Press (US), 2000, www.ncbi.nlm.nih.gov/books/NBK225480/.
- Kahle, Laura E., et al. “Acute Sodium Bicarbonate Loading Has Negligible Effects on Resting and Exercise Blood Pressure but Causes Gastrointestinal Distress.” Nutrition Research, vol. 33, no. 6, June 2013, pp. 479–486, https://doi.org/10.1016/j.nutres.2013.04.009. Accessed 1 Dec. 2019.