The Ultimate Evidence-Based Guide to Pre-Workout Supplements
Pre-workout supplements, or multi-ingredient pre-workout supplements (MIPS), are some of the most popular products in the fitness industry. Whether you’re looking for a boost of energy, improved endurance, or better strength, pre-workouts promise to take your training to the next level. But do they actually work? And how do you choose the right one? In this guide, we’ll break down the science, ingredients, and safety of pre-workout supplements to help you make informed decisions.
What Are Pre-Workout Supplements?
Pre-workouts are designed to be taken before exercise to enhance performance by targeting various aspects such as energy, focus, strength, endurance, and even mood. A 2019 survey of MIPS users revealed the top three reasons for taking pre-workouts were:
Increased energy.
Improved muscular endurance.
Enhanced “muscle pump” (Jagim et al., 2019).
These supplements often contain a blend of active ingredients that are thought to work synergistically to improve workout quality and long-term adaptations.
Key Ingredients in Pre-Workouts: What Works?
The effectiveness of pre-workouts largely depends on their ingredients. Let’s explore the most common ones:
1. Caffeine
Dose: 3-6 mg/kg of body weight.
Benefits: Boosts muscular endurance, movement velocity, strength, and cognitive performance (Guest et al., 2021).
Mechanism: Stimulates the central nervous system and optimizes exercise metabolism.
2. Creatine
Dose: 3-5 g/day.
Benefits: Improves high-intensity exercise performance and supports muscle hypertrophy (Kreider et al., 2017).
Mechanism: Increases intramuscular phosphocreatine stores for better energy availability.
3. Beta-Alanine
Dose: 3.2-6.4 g/day.
Benefits: Delays fatigue during high-intensity efforts (Saunders et al., 2017).
Mechanism: Boosts intramuscular carnosine levels to buffer acid buildup.
4. Citrulline and Nitrates
Dose: 3-8 g/day for citrulline; 400-800 mg nitrate/day.
Benefits: Enhances blood flow, delays fatigue, and improves endurance (Gonzalez & Trexler, 2020; Gonzalez et al., 2023).
Mechanism: Increases nitric oxide production for vasodilation and improved oxygen delivery.
5. Tyrosine
Dose: 1-2 g/day.
Benefits: Enhances focus and cognitive performance under stress (Jongkees et al., 2015).
Mechanism: Supports dopamine and norepinephrine production.
6. Taurine
Dose: 1-2 g/day.
Benefits: Improves endurance and exercise efficiency (Waldron et al., 2018).
Do Pre-Workouts Work?
Acute Benefits
Research shows that a single serving of MIPS can:
Improve force production and muscular endurance.
Reduce perceived exertion during training.
Enhance subjective feelings of energy, focus, and alertness (Beyer et al., 2024; Spradley et al., 2012).
Chronic Benefits
When taken consistently over weeks, pre-workouts can:
Support body composition improvements (e.g., increased lean mass, reduced fat mass).
Enhance training adaptations by improving workout quality over time (Harty et al., 2018).
However, effectiveness varies depending on the formulation, as ingredient dosages are not standardized across brands.
Safety Considerations
Short-Term Safety
Most pre-workouts are safe for short-term use, but common side effects include:
Gastrointestinal distress.
Increased blood pressure.
Sleep disturbances when consumed too close to bedtime (Eudy et al., 2013).
Long-Term Safety
Research on long-term MIPS use is limited. It’s important to:
Avoid excessive caffeine intake, especially if combined with other caffeinated products.
Consult a healthcare professional if you have underlying medical conditions or take medications.
Proprietary Blends
Many products use proprietary blends, which obscure the exact dosages of ingredients. This lack of transparency can make it difficult to evaluate a product’s effectiveness.
Third-Party Testing
Look for third-party certifications such as NSF International or Informed Choice. These organizations test for purity, potency, and contamination, providing an added layer of safety (Jagim et al., 2023).
Should You Use Pre-Workouts?
Who Can Benefit?
Beginners: Likely unnecessary; focus on good nutrition and training first.
Intermediate and Advanced Lifters: Can be a useful tool to enhance performance.
Endurance Athletes: May benefit from nitric oxide boosters and caffeine for improved stamina.
Who Should Avoid Them?
Individuals with caffeine sensitivity.
Those with medical conditions without prior consultation.
How to Choose the Right Pre-Workout
Check the Ingredients: Look for effective doses of proven ingredients like caffeine, creatine, and citrulline.
Avoid Proprietary Blends: Opt for transparent labels.
Look for Third-Party Testing: Certifications like NSF or Informed Choice ensure quality and safety.
Start Small: If you’re new to pre-workouts, start with half the recommended dose to assess tolerance.
Final Thoughts
Pre-workouts can be a valuable addition to your fitness routine, but they’re not magic. Training, recovery, and nutrition are still the cornerstones of progress. Use pre-workouts as a tool to enhance your performance, not as a crutch.
Always prioritize products with evidence-backed ingredients, effective dosages, and third-party testing to ensure safety and effectiveness. With the right approach, pre-workouts can help you push harder, recover faster, and achieve your fitness goals.
References
Beyer, KS, et al. (2024). Frontiers in Nutrition.
Guest, NS, et al. (2021). Journal of the International Society of Sports Nutrition.
Gonzalez, AM, & Trexler, ET. (2020). The Journal of Strength and Conditioning Research.
Harty, PS, et al. (2018). Journal of the International Society of Sports Nutrition.
Kreider, RB, et al. (2017). Journal of the International Society of Sports Nutrition.
Saunders, B, et al. (2017). British Journal of Sports Medicine.
Spradley, BD, et al. (2012). Nutrition and Metabolism.
Waldron, M, et al. (2018). Sports Medicine.