Here are the top ingredients to look for in your pre-workout cocktail to energize your next training session – and your results
By Trevor Kouritzin, PhD, MSc, B. Eng.
Maximizing gains in strength or muscle size – or any other training goal, for that matter -- involve integrating several fundamental components. You must get adequate amounts of sleep, eat like a champion, and train intensely and regularly. In recent years, science has shown that precise timing and stacking of supplements, specifically pre-workouts, elicit synergistic effects on muscular growth and strength. And their benefits aren’t limited to just resistance training.
The goal of pre-workout supplementation is to set up the perfect environment to promote energy levels and enhance exercise performance during high-intensity workouts. When used as part of a balanced diet, they can act as a catalyst for a host of improved training outcomes, including higher and more sustained energy levels, better endurance, delayed fatigue, increased alertness, muscle growth, reduced muscle soreness, speedier recovery, and enhanced fat loss.
If you’re considering adding a pre-workout to your diet, you’ll want to understand how it works, its key ingredients, and its benefits, which we’ll cover here.
Types of Pre-Workout Formulas
Pre-workouts can be broken into two groups:
High stimulant pre-workouts:
High stim pre-workouts with caffeine, a central-nervous system stimulant (found naturally in coffee beans, tea leaves, cacao beans, guarana berries, and yerba mate) quickly boost alertness, energy levels, cognitive function, and athletic performance. Caffeinated pre-workout formulas typically contain about 200 mg of caffeine (check the label), which is slightly more than double what you’d get in the average cup (8 oz.) of coffee.
Stimulant free pre-workouts:
Other pre-workout products are stimulant-free, which can be beneficial if you train closer to bedtime or are highly sensitive to caffeine, which can cause jitteriness or anxiousness among some users or if overconsumed. Taken too late in the day, caffeine can also interfere with the quality and length of your sleep. If you have a medical condition like high blood pressure, use caffeinated products only under the supervision of your doctor.
Common Ingredients and their Benefits
Well-formulated nutritional supplements include ingredients that help achieve multiple goals. Here’s a short list of what you should be looking for:
Caffeine
As noted, caffeine is commonly regarded as a potent natural stimulant by increasing energy and focus, useful if you need a pick me up before hitting the weights. It has repeatedly been shown to be an effective ergogenic aid in both endurance exercise and high-intensity anaerobic activity.
In a position statement, the International Society of Sports Nutrition stated: “Energy drinks and pre-workout supplements containing caffeine have been demonstrated to enhance both anaerobic and aerobic performance. …Supplementation with caffeine has been shown to acutely enhance various aspects of exercise performance in many but not all studies. Small to moderate benefits of caffeine use include, but are not limited to: muscular endurance, movement velocity and muscular strength, sprinting, jumping, and throwing performance, as well as a wide range of aerobic and anaerobic sport-specific actions.”1
A randomized controlled trial published in the Journal of Science and Medicine in Sport found that caffeine supplementation resulted in significantly faster cycling time-trial performance. Participants in the caffeine group completed the trial 6.7 percent faster (273 seconds quicker) than the placebo group.2
ISSN specifically cites caffeine’s benefits for aerobic exercise: “Aerobic endurance appears to be the form of exercise with the most consistent moderate-to-large benefits from caffeine use, although the magnitude of its effects differs between individuals.”1
Caffeine has been shown to decrease rates of fatigue and lower perception of effort, which may be of benefit during high-intensity, high-volume workouts. Studies have also confirmed that pre-workout caffeine supplementation reduces muscular soreness by greater than 50 percent. For energy purposes, caffeine is intimately involved in increasing fat mobilization from fat cells into the circulation and reducing perceived exertion during exercise.3,4
Though less studied, caffeine is effective in weight loss, too. A study published in the European Journal of Clinical Nutrition found that individuals who maintained a weight loss of greater than 5 percent of their total weight for at least a year consumed significantly more caffeine than the other group.5
Beta-Alanine
According to the ISSN, beta-alanine significantly augments muscle carnosine concentrations, which act as an intracellular pH buffer, notably delaying fatigue and increasing power production and work capacity, with notable improvements in exercise performance after 4-6 weeks with 4-6 g of supplementation.6
One study demonstrated its effectiveness in reducing muscle fatigue by increasing total exercise volume, endurance, and work capacity. A study published in Amino Acids found that 28 days of beta-alanine supplementation significantly improved high-intensity cycling performance in female cyclists. The beta-alanine group saw a 23 percent increase in time to exhaustion (TTE) and a 21 percent increase in total work completed (TWC), compared to just 1 and 2 percent, respectively, in the placebo group.7
Citrulline Malate
L-citrulline is a non-essential amino acid that’s found primarily in watermelons, cucumbers, and other melons Because of its ability to be converted to L-arginine via the urea cycle, L-citrulline serves as a nitric oxide (NO) precursor with the potential to increase blood flow and augment resistance exercise performance.
Citrulline malate is L-citrulline combined with malic acid, which is believed to increase absorption rate and bioavailability. It has been shown to enhance muscle pump and blood flow (think nitric-oxide enhancer), delaying muscle fatigue and improving performance during high-volume resistance exercise. A study published in the Journal of Strength and Conditioning Research demonstrated that participants who ingested citrulline malate were able to complete 9 percent more repetitions during lower-body exercises compared to a placebo group. This performance boost is attributed to citrulline malate’s ability to enhance blood flow and delay fatigue.8
Dosage and Timing
Check product labels for recommended dosage, but in general a serving of caffeine that’s about 200 mg is recommended, but that’s a general guideline that’s best tailored to your body weight. For improvements in exercise performance, ISSN recommends 3-6 mg/kg of body mass, meaning a 180-pound individual might consume 200-400 mg caffeine before a workout.1 Very high doses of caffeine (e.g. 9 mg/kg) are associated with a high incidence of side effects and don’t seem to be required to elicit an ergogenic effect. Minimal effective doses of caffeine currently remain unclear but they may be as low as 2 mg/kg body mass.1
How fast you metabolize caffeine can depend on whether you eat a meal with your pre-workout supplement. It’s best to take a pre-workout when full for slow-release effects; however, using pre-workout supplements on an empty stomach can speed up digestion for faster reaction times.
Another consideration: Pre-workouts perform better when taken consistently as opposed to intermittently, as the main ingredients build up within your system. If you take products regularly for three weeks, you should experience longer-lasting workouts and see a reduction in tiredness after exercise, so long as you don’t take too much.
Caffeine is a known diuretic, but it does not seem to have a significant effect on overall fluid balance, according to research. Still, always drink plenty of water to ensure you stay well-hydrated and enough so that your urine is clear. Dehydration adversely affects your performance and can contribute to adverse health issues.
Ideal dosages of beta-alanine for notable improvements in exercise performance after 4-6 weeks include 4-6 g of supplementation. To prevent tingling, a reported side effect, choose an extended-release formula or divide your daily dose into multiple servings.
For citrulline malate, a dose of 6-8 grams daily is recommended.
The Bottom Line on Pre-Workout Supplements
Pre-workout supplements help boost your energy, focus, and exercise performance independent of whether you engage in aerobic or anaerobic activity. For some ingredients, maximal effectiveness is best achieved with consistent usage. Because of some side effects, caution is advised not only when you take your pre-workout but also how much. Pay attention to label instructions and how your body responds.
References
1 Guest, N.S., VanDusseldorp, T.A., Nelson, M.T. et al. “Full article: International society of sports nutrition position stand: caffeine and exercise performance” Journal of International Society of Sports Nutrition, 18, 1 (2021).
2 Pitchford, N. W., Fell, J. W., Leveritt, M. D., Desbrow, B., & Shing, C. M. (2014). “Effect of caffeine on cycling time-trial performance in the heat - ScienceDirect.” Journal of Science and Medicine in Sport, 17(4), 445–449.
3 Costill, D. L., Dalsky, G. P., & Fink, W. J. (1977). “Effects of caffeine ingestion on metabolism and exercise performance. - Abstract - Europe PMC.” Medicine and Science in Sports and Exercise,10(3), 155-158.
4 Arciero, P. J., Bougopoulos, C. L., Nindl, B. C., & Benowitz, N. L. (2000). “Influence of age on the thermic response to caffeine in women - ScienceDirect.” Metabolism: Clinical and Experimental, 49(1), 101-107.
5 Icken, D., Feller, S., Engeli, S. et al. “Caffeine intake is related to successful weight loss maintenance | European Journal of Clinical Nutrition.” European Journal of Clinical Nutrition, 70, 532–534 (2016).
6 Trexler ET, Smith-Ryan AE, Stout JR, Hoffman JR, Wilborn CD, Sale C, Kreider RB, Jäger R, Earnest CP, Bannock L, Campbell B, Kalman D, Ziegenfuss TN, Antonio. “International society of sports nutrition position stand: Beta-Alanine | Journal of the International Society of Sports Nutrition, 2015 Jul 15;12:30.
7 Glenn, J. M., et al. (2015). “Incremental effects of 28 days of beta-alanine supplementation on high-intensity cycling performance and blood lactate in masters female cyclists | Amino Acids ” 47(12), 2593–2600.
8 Wax, B., Kavazis, A. N., Weldon, K., & Sperlak, J. (2015). “The Journal of Strength & Conditioning Research.” Journal of Strength and Conditioning Research, 29(3), 786–792.
