Whether your aim is to build more muscle, improve performance and focus, or give yourself an energy boost, it’s important to do your research.
We’ve sifted through the research to show you:
- Pre-workout ingredients guaranteed to work
- Ingredients you need to be wary of
- Which ingredients you should most definitely avoid.
Table of Contents
Ingredients That Work
The holy grail of energy.
Caffeine works by preventing the relaxation molecule adenosine from interacting with the brain. This raises the number of neurons that fire in the brain, which then releases “fight or flight” hormones like adrenaline.
Although its effects can vary depending on your individual tolerance, the benefits of caffeine in health and performance are very clear.
Caffeine supplementation to improve exercise performance is well-studied, especially resistance exercise:
- A 60mg dose increased repetitions in both the bench press and leg press (1).
- A 5mg/kg dose was shown to increase repetitions during the bench, loaded row, deadlift and back squat (2).
- Even caffeine from a standard energy drink has been shown to increase strength by 5% in the knee extensors (3).
Examine.com agree that 200mg of caffeine is useful for fat-burning, but doses of 500mg and above are necessary for strength and performance gains.
Researchers tend to use a dose between of 4-6mg/kg of body weight, which consistently increases power output in both trained and untrained individuals (4).
Note that those with a high caffeine tolerance or threshold require greater doses.
Key Tip: Take caffeine at 5-6mg/kg, about 45 mins before a strength workout.
Beta-alanine works by maintaining the pH level in the muscle. This reduces the burning and heaviness feelings in the muscle during intense exercise.
The burn is a predictor of muscular fatigue and therefore beta alanine may improve exercise performance.
Examine.com note that beta-alanine enhances muscular endurance and that people are able to perform one or two additional reps when resistance training.
Large doses of beta-alanine can cause a tingling sensation known as paresthesia. It’s not harmful but some people do find it uncomfortable.
Key tip: Either take one 2-5 grams dose pre-workout, or 1 gram for 2 to 5 times daily.
It’s stored in the muscle to increase your ability for quick bursts of energy (9).
Because it increases energy reserves, creatine has both health and performance benefits.
Study after study show that creatine improves muscle strength and size.
In one study, an increase of 1-2 kg of total body mass was not uncommon after 4 weeks of supplementation. Improvements in arm curl muscle strength were almost double (+12 kg vs. +7 kg) for the creatine users (10).
But how should you supplement with it?
Creatine monohydrate is the most effective. The micronized version dissolves in water more easily, which can be practical too.
You can use a loading period to top up your creatine stores quicker, but it isn’t necessary. Studies show that creatine levels are similar after about 3 weeks whether you load or not (11).
Key Tip: Supplement with a 3 gram dose 60 mins pre-workout as well as on your off-days. Alternatively, supplement with 20 grams per day for 5-7 days and then continue with 2 grams daily.
Nitrate increases the diameter of blood vessels around the working muscle. This allows more blood to flow to the muscle and increases its oxygen supply.
Examine.com report that nitrate increases exercise performance by reducing the oxygen cost of exercise and lowers the rate of fatigue in more intense muscle contractions.
In practice it improves exercise that ranges between 1-10 minutes long, such hockey, rugby, rowing and crossfit-type exercises.
If you’re using low rest periods or higher repetition sets as well as high intensity exercise you might benefit from supplementing with nitrate. In fact, nitrates from beetroot juice can keep your going 14% longer in exhaustive exercise (12).
Key tip: Supplement with at least 8 mmol of nitrate either in beet juice or powdered form. Higher doses don’t seem to be any more effective.
HMB (β-Hydroxy β-Methylbutyrate) is a form of amino acid used to prevent muscle breakdown. Because of this, it’s used pre-workout, especially for resistance training individuals.
HMB supplementation to improve resistance training outcomes are well studied:
- Decreases in muscle breakdown during and after the workout (13).
- Muscle strength gains are improved by 2-17% when accompanied by a progressive strength training routine.
- Lower muscle soreness in the days following resistance training (14).
Using HMB post-workout has no effect, which shows that timing is everything.
Examine.com note that compared to Leucine (a similar amino acid), HMB is more potent gram for gram and therefore better at reducing muscle protein breakdown.
Key tip: Take 1-3 grams about 30 to 45 min before the workout. Use a free acid HMB supplement rather than a calcium salt.
Ingredients that Might Work
Citrulline is an amino acid with similar effects to nitrate.
It works slightly differently by increasing levels of arginine in the blood, which also increases blood flow.
Although arginine supplements are not effective (more below), citrulline is absorbed very well, and therefore may be an ideal way of increasing blood flow to the working muscle during exercise.
Examine.com support citrulline as an effective pre-workout supplement. It appears to reduce fatigue and improve endurance for both short and long bouts of exercise.
Additionally, when taken pre workout, citrulline malate increases the number of repetitions in the bench press by 50% and decreases muscle soreness for the following 2 days after exercise (15).
One case study found the supplement increased muscle mass by 4 kg and reduced fat mass by 2 kg after 8 weeks of resistance training. The individuals were also taking glutamine and BCAA’s, however it’s likely citrulline provided much of the effect (16).
Key tip: Take 6 to 8 g of citrulline malate about an hour before exercise.
Sodium bicarbonate works by clearing by-products from the muscle, which help to cause fatigue during exercise.
It does this by raising the levels of bicarbonate in the blood and absorbing molecules that can cause “the burn” (metabolic acidosis) during intense exercise.
Examine.com recommend taking 200-300 mg/kg as this dose reliably benefits performance when exercise failure is caused by metabolic acidosis, rather than the nervous system.
To put another way, supplementing with sodium bicarbonate isn’t going to give you a bigger bench or a higher V02 max.
However, studies show that sodium bicarbonate can increase 30-second all out cycling sprint performance and help you last longer before exhaustion sets in (17).
One long term study even showed a greater improvement in a measure of fitness (lactate threshold) after 8 weeks of training, probably because the individuals could work harder during the workouts (18).
Bicarbonate does not improve maximum muscle strength, but it might increase the total number of repetitions you can perform during resistance training workouts, and therefore improve your chances for muscle gain (19).
Key tip: Sodium bicarbonate works best when using 0.3g/kg of body weight about 60 min pre workout.
Ingredients that Don’t Work
L-arginine was one of the hottest supplements that promised to boost nitric oxide and enhance the “pump”. However, study after study shows no such effect.
Examine.com don’t recommend arginine either, and report that the effects are unreliable and just as many studies that show no effect than those showing greater levels of nitric oxide.
A study in male judo athletes reported no effect of arginine on either blood flow or exercise performance when taken pre workout (20).
Key tip: stay away from nitric oxide boosters that name L-arginine as a main ingredient.
Glutamine is the most abundant amino acid in the body.
It plays a key role in the immune system and may aid in the health of the gastrointestinal system, reduce muscle wasting, and help stabilise blood sugar levels.
However, glutamine doesn’t stack up as a pre workout.
A large scale study assessed the effect of high dose glutamine on the number of bench press and leg press repetitions that could be performed, and compared it with taking a placebo (21).
Researchers found zero effect of glutamine in either exercise. Therefore as a pre workout supplement, especially for weight training, glutamine does not provide any improvement in performance.
Key tip: While glutamine may aid in high stress environments and support the immune system, its use is not beneficial as a pre workout.
When looking for a pre-workout supplement, the tried and tested ingredients still seem to be the greatest.
You’ll put yourself in the best position possible by sticking to these top 5:
- Sodium Bicarbonate
Some other ingredients on the market may benefit your training, but the results aren’t nearly as solid.