Not all pre-workout supplements are created equal. In fact, most if not all pre workouts, are drastically different. Whether that’s regarding the dose, specific ingredients, or if they stimulants like caffeine, and or added sugars. Often times, pre workout can cause side effects, including headache, nausea, digestive and stomach issues, and water retention. If you’re experiencing some of these side effects, adjusting the dosage, or avoiding certain ingredients all together, may help.

What Are Pre-Workout Supplements 

Many people use pre workout supplements to boost energy and to produce enhanced performance outcomes from training. Pre workouts are often split amongst two categories – stim or non-stim. Some pre workout supplements contain stimulants like caffeine, or natural stimulants such as green coffee bean, while others do not contain any stimulants at all. Non-stim pre workout supplements are created with specific sports nutrition ingredients, to help improve athletic performance, strength, endurance, and build more muscle mass, not to produce an immediate response and boost your acute energy before your workout. 

Yet, some people experience negative side effects from pre workout supplements regardless of stimulants or not.

Side Effects Of Pre-Workout

1. May Make You Feel Jittery 

Caffeine is one of the primary and most common ingredients found in pre workout supplements and is considered a stimulant.

Caffeine has been shown to improve performance and prolong exercise in doses between 3 and 13mg/kg of bodyweight. 

Caffeine is technically a psychoactive drug, meaning it directly affects your brain. Caffeine stimulates nervous system activity, increasing wakefulness and alertness.

It produces neural excitation, and stimulates the release of adrenaline. 

Studies investigating the effects of caffeine on exercise performance have found positive benefits, on exercise endurance and muscular strength [R].

However, caffeine may exert some negative side effects, such as making you jittery, causing irritability, high heart rate, nausea, and anxiety. Effects do vary individually and is largely mediated by our genes. Higher doses of caffeine do not exert or result in additional improvement in physical performance [R].

Caffeine dosage is individualized, therefore be conscious of how much caffeine your pre workout may have. If you are highly sensitive to caffeine, consider taking a non-stim pre workout such as Swolverine.

Very high doses of caffeine (e.g. 9 mg/kg) are associated with a high incidence of side-effects and do not seem to be required to elicit an ergogenic effect.

2. Upset Stomach And Digestive Issues 

If you have a sensitive stomach or digestive issues, several pre workout ingredients may cause upset stomach or digestive issues such as magnesium and caffeine.

Magnesium especially in the form of magnesium citrate can have a laxative effect. Not using enough water when mixing your pre workout can also cause upset stomach and digestion issues. Too high of a concentration can often lead to diarrhea.

Niacin can also cause stomach discomfort and bloating, with higher doses of 50mg or more [R].

3. Headache

Several pre workout ingredients taken above the recommended dose may cause headache. 

Ingredients such as arginine, citrulline, and niacin, are vasodilators, increasing blood flow throughout the body, including the brain. More blood blow and an expansion in the volume of vessels may cause headache to occur. 

4. Tingling Or Flushing 

Two common pre workout ingredients, Beta-Alanine and Niacin (Vitamin B3) can cause side-effects of mild discomfort. Beta-Alanine an amino acid that helps reduce muscle fatigue by buffering hydrogen ions, and causes a biological reaction called paresthesia, a tingling sensation within the surface of the body. This side effect is non-harmful nervous system reaction, that activates sensory neurons that terminate in the skin, leading to topical tingling and itchiness [R].

Niacin a common pre workout ingredient can cause mild discomfort with flushing of the skin. Skin flushing, or blushing, happens due to increased blood flow. This effect is referred to as "niacin flush," which is a burning, tingling sensation in the face and chest, and red or flushed skin. Other side effects may include diarrhea, headache, stomach discomfort, and bloating with doses of 50mg or higher [R].

Vitamin B3 plays an important role in energy metabolism, similar to other b-vitamins. However too much niacin, of doses higher than 1,000mg can cause diminishing returns and negatively affect exercise performance [R].

Pre-Workout Side Effects: Takeaway

It’s important to remember, that each person’s biology is different. Some may be intolerant or hypersensitive to certain ingredients, while others may not be. At Swolverine we combine whole superfoods like pomegranate, beets, and coconut water with proven ingredients and the correct clinical doses, found in research to elicit and produce clear ergogenic benefits to minimize any side effects associated with pre workout supplements. At the correct dose, pre workout supplements can improve exercise performance. Most pre workouts however are under-dosed and therefore do not produce any benefit at all. You have to find what works well for you. Limiting certain ingredients may help, however none of these ingredients are found to be harmful at the respected doses and are all approved by the FDA for human consumption and use.  

Looking For The Best Pre Workout For Your Performance?

SWOLVERINE IS AN ENDURANCE ATHLETE AND ACTIVE LIFESTYLE BRAND. MADE FOR THE ELITE ATHLETE, AND THE STRONG-WILLED OUR PRODUCTS WERE DESIGNED TO FUEL YOUR ATHLETIC PERFORMANCE. WE PERFORM WHEN YOU PERFORM. 

We believe that everyone can optimize not only their athletic performance but their human potential. The way we believe we can optimize performance is through transparency, clinically effective doses, and clinically proven ingredients with evidence-based outcomes. We provide the nutrients you need to power your active lifestyle.