Pre-workout supplements offer several benefits, such as increased energy, enhanced focus, bigger pumps, and better exercise performance. The pre-workout category dominates the sports nutrition industry as one of the most popular and saturated categories.
Nearly every supplement company offers at least one and several types of pre-workout supplements. Pre-workouts are usually categorized by their stimulant content, such as high-stim, moderate-stim, low-stim, and non-stim.
Those new to pre-workout supplements tend to buy based on price, marketing tactics, and flavor. However, it’s crucial to look at the pre-workout formula to see if there are any ingredients that may cause unwanted side effects.
A common side effect of taking a pre-workout supplement, especially stimulant-based pre-workouts, is making you poop. You may also notice a similar effect after drinking a cup of coffee. But why is this the case? This article will cover why pre-workout increases the urge to go to the bathroom and what ingredients prompt it!
Table of Contents
Why Does Pre-Workout Make You Poop?
It is true that drinking a pre-workout supplement can increase the chance of bowel movements, but that’s not the case for everyone. Whether a pre-workout makes you poop or not usually depends on a variety of factors, such as:
- Ingredients
- Dosages
- Individual
- Timing
- Fasted or non-fasted
A pre-workout supplement makes you poop because they contain a high amount of a specific ingredient, such as caffeine. Or the combination of ingredients found in the pre-workout isn’t sitting well with your digestive tract.
Since pre-workout supplements often have quite sophisticated formulas, it can be difficult to decipher which ingredient is the cause. Various non-active ingredients are added to pre-workouts to make them taste or mix better, which may also cause side effects.
Below, we will cover common pre-workout ingredients that can make you poop.
Common Pre-Workout Ingredients That Can Make You Poop
Here are some of the most common pre-workout ingredients that can make you poop and why!
Caffeine
Caffeine is one of the most well-researched ingredients in the dietary supplement industry. It’s been shown repeatedly to be safe and effective for increasing exercise and mental performance. With that said, caffeine does have its side effects…
Since caffeine stimulates your bowels, specifically the colon, it results in the urge to defecate. So if you’re sensitive to caffeine or trying out a high-stim pre-workout, don’t be surprised if you end up on the toilet shortly after.
Whether you’re drinking pre-workout, a coffee, or an energy drink, more likely than not, it will increase the chance of making you poop. If there’s one thing that most pre-workouts, energy drinks, and coffee have in common, they all contain caffeine.
Most pre-workout supplements contain a much higher amount of caffeine than an average cup of coffee. For example, a pre-workout often contains between 150 milligrams to over 400 milligrams of caffeine. In contrast, a coffee cup contains more than 100 milligrams of caffeine.
Artificial Sweeteners & Sugar Alcohols
To make pre-workouts tasty, they are often filled with artificial sweeteners and/or sugar alcohols, such as:
- Sucralose
- Acesulfame-K
- Aspartame
- Erythritol
- Maltitol
- Sorbitol
A pre-workout will often use a combination of the non-nutritive sweeteners listed above, and the amounts are usually not disclosed. However, most pre-workout ingredients don’t taste that good, so they have to add quite a bit to create the flavor they desire. At the end of the day, if the pre-workout doesn’t taste good, you’re probably not going to keep using it.
Large amounts of sugar alcohols and/or artificial sweeteners can lead to gastrointestinal distress, such as diarrhea, because they aren’t absorbed well in the digestive tract. That’s also one of the reasons why they don’t contribute as many calories as regular sugars, such as dextrose or sucrose.
If you are taking pre-workout, you are probably using other supplements (e.g., protein powders, protein bars, amino acids, etc.) that also use non-nutritive sweeteners. Over time, consuming excessive amounts of artificial sweeteners may negatively impact your gut.
Less Common Pre-Workout Ingredients That Can Make You Poop
So far, we’ve covered the two most common culprits that make you poop after drinking pre-workout. Some other ingredients may contribute to the urge to have a bowel movement.
High Doses of Vitamin C
Vitamin C isn’t as common in pre-workout supplements as caffeine or artificial sweeteners. But many pre-workouts with nitrates to promote nitric oxide production also contain high doses of vitamin C to avoid building up a tolerance to nitrates. Vitamin C has a laxative effect when taken in high doses.
Vitamin C seems capable of increasing gastric motility, which means it speeds up the digestive process. The amount of vitamin C it takes to elicit a bowel movement varies depending on the person, but for most people, it’s somewhere between 2,000 milligrams and 4,000 milligrams.
However, most pre-workouts will not contain more than 1,000 milligrams of vitamin C. If you are taking a multivitamin or high-dose vitamin C supplement on top of this, that could be problematic. Keep your daily vitamin C intake in check to avoid this.
High Doses of Sodium Bicarbonate
Sodium bicarbonate, also known as baking soda, is added to some pre-workouts for the performance benefits and to give the pre-workout drink a carbonated effect. If a company is trying to create a cola flavor, adding some sodium bicarbonate enhances the user experience, or it will taste like a flat soda.
Sodium bicarbonate is most commonly used by endurance athletes because it may improve muscular endurance and time to exhaustion. However, consuming too much sodium bicarbonate can cause diarrhea and vomiting because the body draws more water into the digestive system to correct the electrolyte imbalance.
High Doses of Magnesium
Another ingredient that has a laxative effect when taken at high doses is magnesium, an essential trace mineral. Magnesium increases the amount of water in the digestive tract, thereby encouraging bowel movements. Additionally, since there are various types of magnesium, the type of magnesium consumed matters.
Magnesium citrate is the most commonly used form for treating constipation, but this also depends on the person and dose. For most people, taking between 200 milligrams and 500 milligrams will increase the frequency of bowel movements.
How to Avoid Pre-Workout Poops
If you want to avoid running to the bathroom after drinking pre-workout, here are some tips!
- Use a non-stimulant pre-workout or a low stimulant pre-workout
- Limit your artificial sweetener intake and avoid pre-workouts with sugar alcohol
- Avoid high doses of vitamin C, sodium bicarbonate, and magnesium
- Timing and dosing
Use a Pre-Workout Without Caffeine
If you are sensitive to caffeine, train late at night, or want to avoid the pre-workout poops, stick to a non-stimulant pre-workout. But if you still want some stims, look for a pre-workout with under 150 milligrams of caffeine per serving. You can always take half a scoop of a stimulant-based pre-workout to see how your body responds.
A good non-stimulant pre-workout contains ingredients that increase performance, pumps, and focus. Look for one that uses a fully disclosed label, so you know exactly how much of each ingredient is included in one serving.
Limit Your Artificial Sweetener Intake and Avoid Sugar Alcohols
Most pre-workouts that contain sugar alcohol are marketed as naturally sweetened. Even if that is the case, sugar alcohols are far more likely to cause GI distress than artificial sweeteners. Finding a clean pre-workout powder that’s naturally sweetened and only contains stevia extract and/or monk fruit is challenging. But if you do find one, give it a shot!
If you still want to enjoy your artificially sweetened pre-workout, try to cut back on the artificial sweeteners you may be consuming elsewhere, such as adding Splenda to your coffee, sipping on branched-chain amino acids or essential amino acids during training, and consuming protein powder after training. All of those add up and can lead to stomach upset.
Avoid High Doses of Vitamin C, Sodium Bicarbonate, and Magnesium
Extremely high doses of vitamin C, sodium bicarbonate, and magnesium are not super common in pre-workouts, but it’s something to look out for. Also, stacking a multivitamin or individual vitamins/minerals on top of the pre-workout may quickly reach the limit your body and bowels can handle.
The best way to avoid having to poop is by checking the supplement facts panel on the pre-workout. Also, it’s a good idea to take your multivitamin and/or vitamins/minerals away from the workout window.
Timing and dosing
Whether you work out early in the morning, in the afternoon, or late at night, it could impact how the pre-workout supplement reacts with your body. If you prefer training first thing in the morning in a fasted state, the pre-workout will kick in much faster and more likely to cause a bowel movement.
Vice versa, taking a pre-workout later in the day when you have a good amount of food in your system, bowel movements and stomach upset is less likely to happen because it takes slightly longer for the pre-workout to kick in.
In terms of dosing, start with half a serving of pre-workout to assess your tolerance. You may notice that half a scoop feels good, but a full scoop results in various unwanted side effects. Then you can scale the dose accordingly. Also, if you have a kitchen scale, it’s a good idea to weigh your pre-workout instead of relying on the measuring scoop because it could be way off.
Frequently Asked Questions
Does pre-workout cause diarrhea?
Yes, pre-workouts can cause diarrhea, especially with high amounts of stimulants, vitamin C, magnesium, sodium bicarbonate, or sugar alcohol. Not all pre-workouts are the same, and everyone responds differently.
We recommend checking the supplement facts panel, only using pre-workouts with fully transparent labels, and starting with half a scoop to assess your tolerance. Other factors can contribute to diarrhea, such as your diet, when you took the pre-workout, how much water you consumed, and if you did an intense workout session.
How long does pre-workout diarrhea last?
How long pre-workout diarrhea lasts depends on the person. If diarrhea lasts more than 12-24 hours, you may want to visit a qualified healthcare professional.
Does pre-workout always cause diarrhea?
No, a pre-workout does not always cause diarrhea. If you notice frequent diarrhea from taking pre-workout, reduce the serving, discontinue use, and speak with a qualified healthcare provider.
What is the best way to avoid pre-workout-induced pooping?
The best way to avoid pre-workout-induced pooping include:
- Use low-stim or non-stim pre-workout supplements
- Don’t use pre-workouts with high doses of magnesium, vitamin C, or sodium bicarbonate
- Don’t use pre-workout with sugar alcohol
- Limit your artificial sweetener intake around training
- Don’t take pre-workout on an empty stomach
- Start with half a serving to assess your tolerance
Summary
Pre-workout supplements are extremely popular, and for a good reason! The best pre-workout supplements contain various ingredients that may increase exercise performance, such as strength, power, and endurance.
Pre-workouts can boost mental performance, such as energy, focus, and alertness. With that said, pre-workouts can cause unwanted side effects, especially involving the digestive system.
The pre-workout ingredients most likely to make you poop are caffeine and other stimulants, vitamin C, magnesium, sodium bicarbonate, artificial sweeteners, and sugar alcohols.
If you want to avoid the pre-workout poops, inspect the pre-workout formula to ensure it doesn’t contain anything that may not agree with your stomach! Also, speak with a qualified healthcare professional before taking any dietary supplement.
