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Pre-Workout Supplements Side Effects: How to Avoid Them

Many people turn to pre-workout supplements to boost energy levels during exercise. These formulas comprise a flavored mixture of several ingredients, each with a specific role in performance improvement. These pre-workout supplements side effects are:

Mild Reactions

Two additional ingredients are beta-alanine and niacin (vitamin B3) in many pre-workout supplements. Beta-alanine is an amino acid that reduces muscle acidity during exercise, which can help you keep your workout going for a little longer. During high-intensity exercises, they have shown it to boost exercise efficiency and decrease fatigue by consuming 6 grams per day.

Yet this ingredient can cause paresthesia in your hands and feet, which is a tingling sensation. While it is a harmless reaction to the nervous system, it may be uncomfortable for some people. Another ingredient with mild downsides is niacin, which for its skin-flushing effects is included in many pre-workout supplements. It can trigger a blood rush to the surface of your skin at high doses of 500 mg or more, resulting in red patches.

Although niacin also plays an important role in energy metabolism, if you consume a well-balanced diet, supplementing with it does not offer additional benefits. The most effective way to reduce beta-alanine-related tingling is to divide the 6-gram daily dose into 2 separate 3-gram each. Alternatively, you can buy formulas that prevent this side effect from being sustained-release. In the meantime, keeping your niacin dose below 500 mg can prevent flush niacin. You can also buy products that are niacin-free. Just check the ingredients.

Makes You Feel Nervous

Caffeine is one of many pre-workout supplements’ primary ingredients. They have shown it that this stimulant increases muscle strength and output while reducing fatigue during exercise. However, Caffeine enables you to get more out of a particular workout. Caffeine, however, has several potential side effects, if you consume too much. These include sleeplessness, nausea, increased heart rate, drowsiness, headaches, anxiety, jitteriness, or restlessness.

Many pre-workout supplements pack high quantities up to 500 mg per serving of caffeine. Serving sizes range from 10 to 30 grams. By comparison, there is only 95 mg in 1 cup of 240 ml of coffee. Caffeine is individualized, as some people tolerate it better than others.

The best way to reduce side effects is to start with a small dose of a pre-workout caffeinated supplement, increasing your dosage to see what you can tolerate. Remember that the best way to avoid caffeine-related sleeplessness is to avoid for at least 6 hours before bed.

High Blood Pressure

Citrulline in pre-workout supplements may cause headaches during exercise to increase blood flow to your muscles. This amino acid works by increasing your blood’s nitric oxide levels. The recommended dose for citrulline malate is 6 to 8 grams, although many pre-workout supplements offer smaller amounts and may not provide potential benefits.

Keep in mind that this increase in blood flow affects both your brain and muscles, leading to headaches and migraines in some people. This is because of changes in blood pressure in the small blood vessels of your brain. Decreasing your dosage is the most effective way to reduce citrulline side effects. If you find that you are still struggling with headaches, find a pre-workout supplement that does not contain citrulline.

May Cause Digestive Problems

Several ingredients may cause a digestive upset in pre-workout formulas. These include sodium bicarbonate, magnesium, creatine, and caffeine. Magnesium, in the form of magnesium citrate, may have laxative effects. Taking too much can, therefore, lead to diarrhea.

Mixing your pre-workout supplements with less water may also upset your stomach. A liquid that is too concentrated may lead to diarrhea. You can minimize side effects by mixing your pre-workout supplement with at least  8–12 ounces of water. Since it’s hard to determine which ingredient causes digestive problems, try different formulas for pre-workout until you find one that you can tolerate.

May Increase in Water Retention

Another popular ingredient in many formulas for pre-workout is creatine. High-intensity exercise ability and lean body mass gains from exercise have been shown. Although it is most often part of a pre-workout supplement, it is also possible to take creatine alone. The main creatine-related side effects are mild but include water retention, bloating weight gain, and digestive problems.

The creatine has been shown to be safe despite these side effects. By ensuring proper dosage, you can reduce any adverse symptoms. Particularly while taking creatine, it may be hard to avoid a moderate weight gain of 4 to 6 pounds. This is because of the increased retention of water in your muscles.

Bottom Line

If you are taking pre-workout supplements, you may experience side effects, including headaches, skin conditions, tingling, and upset stomach. By decreasing your dosage or avoiding supplements with specific ingredients, you can minimize many of these side effects.


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Terms of Use: The information on this website is provided for educational purposes only and is not intended to provide personal medical advice. If you have questions about a medical condition, consult your doctor or another qualified health provider. Never ignore professional medical advice because of something you have read on this website. The Nutrition Source on this website makes no product recommendations or endorsements.

Naeem Durrani BSc
I am a freelance health and wellness writer. My interests include medical research, and the scientific evidence around effective wellness practices, which empower people to transform their lives.

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