This is How Much Caffeine Your Pre-Workout Should Have

Caffeine is one of the primary ingredients in pre-workout, so you’re probably wondering what the ideal dose is and whether more is better.

Key Takeaways

• Research by the International Society of Sports Nutrition recommends 3 to 6 mg of caffeine per kilogram of body weight, consumed roughly one hour before training.

• Caffeine temporarily narrows blood vessels (causing vasoconstriction), which is the opposite of other pre-workout ingredients (like citrulline). Meaning overdoing caffeine in pre-workout can reduce the effectiveness of other performance-enhancing ingredients.

• An effective dose of caffeine before working out has proven to  improve high-intensity performance, endurance, agility, focus, mood, and alertness.

Why Do Pre-Workouts Have Caffeine In The First Place?

As one of the most popular and widely used central nervous system stimulants, caffeine is known to boost:

• Endurance
• High-intensity exercise performance
• Strength and power
• Focus, alertness, and mood
• Agility

It also boosts resting energy expenditure (REE), allowing you to burn extra calories without doing anything. 

Some research also suggests that caffeine can increase fat oxidation (fat burning) rates, hinting at possible fat loss benefits.

As nutritionist Kris Gunnars notes: 

“Caffeine stimulates the nervous system, which sends direct signals to the fat cells, telling them to break down fat. It does this by increasing blood levels of the hormone epinephrine. Epinephrine, also known as adrenaline, travels through your blood to the fat tissues, signaling them to break down fats and release them into your blood.”

Understanding Caffeine Dosage In Pre-Workout

While beneficial for athletic performance and productivity, caffeine also has some side effects, making getting the correct dose crucial to ensure it provides the associated benefits without the drawbacks. Or, at the very least, the benefits outweigh any downsides.

A suitable dose of caffeine (based on your caffeine tolerance, which I’ll touch on later) allows you to feel more alert and focused. In contrast, too much caffeine will lead to jitteriness, anxiety, and elevated heart rate.

The most common way to track caffeine is in milligrams (mg) per serving, so you’ll typically find the compound and a milligram value next to it. 

Standard caffeine dose ranges in pre-workout supplements are as follows:

• Low: 40 to 100 mg
• Moderate: 100 to 200 mg
• High: 200 to 400+ mg

For instance, Red Leaf’s pre-workout has a low dose of caffeine, with only 40 mg of caffeine per serving, whereas Crack Reloaded is exceptionally high with 500 mg.

However, most pre-workouts on the market generally fall into the moderate range of up to 200 mg per serving.

I recommend starting with a ½ serving to test your tolerance, especially when trying a new pre-workout.

• Related: Check out our Pre-Workout Dosage Calculator to determine how much of each ingredient, including caffeine, should be in your pre-workout.

Caffeine Types in Pre-Workout

When comparing the caffeine content of different pre-workouts, you may notice that they have different sources of caffeine.

The most common ones include:

Natural Caffeine

Natural caffeine is the type of caffeine that people typically think about when discussing caffeine, the type sourced from tea or coffee.

Natural caffeine appears on the ingredient label as tea or coffee bean extract.

One example of a pre-workout that uses coffee bean extract is the Alani Nu Pre-workout, which contains 200mg of caffeine per serving.

Some people choose products with natural caffeine rather than synthetic because it supposedly provides a steadier energy release without a subsequent crash. However, that doesn’t seem to be the case. 

Quick side note: Synthetic caffeine is generally listed simply as caffeine. So, unless the manufacturer has listed their caffeine as natural, organic, or an extract, assume it’s synthetic.

As noted by Registered Dietitian Alina Petre:

“Many claim that synthetic caffeine is absorbed much more quickly than natural caffeine, causing a peak in energy followed by a steep crash. However, there is very little scientific backing to this claim.”

Anhydrous Caffeine (or Caffeine Anhydrous)

Anhydrous caffeine is the most common form used in pre-workout formulas, and similar to natural caffeine, it is derived from plant sources. 

The main difference between natural and anhydrous caffeine is that it is dehydrated after extraction, resulting in a highly concentrated caffeine powder.

Though it may sound like a synthetic caffeine form, anhydrous simply refers to a substance that doesn’t have water.

Think of caffeine anhydrous as a more concentrated powder form of natural caffeine.

Buffered Caffeine

Buffered caffeine is when caffeine is combined with another agent that may offer synergistic effects (combined benefits). 

One example you may have encountered is Dicaffeine malate, which is approximately 75% caffeine and 25% malic acid.

Malic acid is linked to many athletic benefits, but the main advantage of pairing it with caffeine is its ability to diminish digestive distress from consuming caffeine alone.

This pairing helps deliver the benefits of caffeine without stomach upset.

Delayed Release Caffeine

Delayed-release caffeine, also known as time-release caffeine, is specifically made to provide a steadier increase in energy levels by absorbing more slowly. 

This type of caffeine is said to reduce the risk of sudden spikes and drops in energy levels and limit side effects, such as jitteriness and anxiety.

According to research, regular caffeine leads to higher concentrations two to five hours following ingestion.

In contrast, time-release caffeine keeps concentrations higher after eight hours. However, their overall effects don’t appear to differ much.

Optimal Caffeine Dosage Before a Workout

According to the International Society of Sports Nutrition:

“Caffeine has consistently been shown to improve exercise performance when consumed in doses of 3–6 mg/kg body mass. Minimal effective doses of caffeine currently remain unclear, but they may be as low as 2 mg/kg body mass.”

For someone who weighs 80 kilograms (176 lbs), that would be a dose of 240 to 480 mg or as low as 160 mg.

The modality and duration of training don’t appear to make a huge difference, but one thing from that paper stood out to me.

Specifically, taking a dose on the lower end of the above range may be more beneficial before high-intensity activities because caffeine can cause jitters that may affect technique and overall performance.

It’s also worth noting that the FDA recommends no more than 400 mg of caffeine per day for healthy adults.

So, if you take a pre-workout with 400 mg of caffeine per serving (or close to that), consuming other caffeine products may be unsafe during the rest of the day. 

My colleague and chief supplement reviewer of FeastGood.com, Jennifer Vibert, often mentions how she likes to have a daily caffeine budget that still allows her to enjoy a cup of coffee. By being more mindful of her caffeine intake, she can reap the benefits of pre-workouts and still enjoy other caffeine products without hitting her upper limit.

Individual Caffeine Tolerance

Caffeine’s effects can vary significantly from person to person due to tolerance.

People with low caffeine tolerance (typically those not used to consuming caffeine) will only reap the benefits without adverse side effects at lower doses. 

In contrast, people with high tolerance (typically those who regularly consume caffeine) need higher doses to experience the same positive effects. They are generally at a lower risk of side effects.

The only way to assess your caffeine tolerance is to start with a lower dose and see how it feels. 

If you start with 100mg or less and experience side effects like anxiety, jitteriness, or heart palpitations, your tolerance is low.

If you can consume 400mg or more without feeling any effects (good or bad), then your body has a high caffeine tolerance. 

Rather than increasing your caffeine intake beyond 400mg to elicit performance-enhancing effects, I recommend limiting your caffeine intake for at least a week to lower your tolerance level.

• Related Article: Should You Cycle Off Pre-Workout?

Caffeine Timing and Pre-Workout

Taking caffeine around one hour before training is generally recommended because plasma levels are thought to peak 45-60 minutes after ingestion.

Here is some insight from Nelson et al.:

“The most commonly used timing of caffeine supplementation is 60 min pre-exercise. Optimal timing of caffeine ingestion likely depends on the source of caffeine. For example, as compared to caffeine capsules, caffeine chewing gums may require a shorter waiting time from consumption to the start of the exercise session.”

Since we are talking about caffeine in pre-workouts, it’s safe to assume that levels will likely peak within an hour, so it’s probably best to take your supplement one hour before training.

This is also the case for pre-workouts containing a delayed-release caffeine form. While caffeine concentrations peak later (up to eight hours after ingestion), the actual effect doesn’t seem to differ much from regular caffeine.

Why Do Some Pre-Workouts Pair Caffeine With L-Theanine?

L-theanine is an amino acid primarily found in tea (e.g., green tea) and certain mushrooms. It is known to promote calmness without making you sleepy.

Theanine does so by reducing the activity of certain neurotransmitters in the brain associated with anxiety. 

It’s also known to promote feelings of well-being thanks to its ability to increase neurotransmitters like dopamine and serotonin, which are associated with mood improvements.

Some pre-workout manufacturers combine caffeine with l-theanine because the two compounds complement one another quite well. 

Caffeine temporarily blocks adenosine receptors in the brain, which delays fatigue and brings most of the associated benefits. However, since it’s a central nervous system stimulant, it may also lead to anxiety, jitteriness, and an elevated heart rate.

L-theanine offsets these effects by promoting calmness without reducing caffeine’s performance-enhancing effects. As a result, you get to enjoy the benefits of caffeine and feelings of well-being without side effects, resulting in better performance. 

High Caffeine + High Pump Products Might Make You Sick

While praised for its performance and mood benefits in a dose-dependent manner (i.e., the effects typically increase with larger doses), having too much caffeine as part of a pre-workout is not ideal.

The primary reason is that caffeine is a vasoconstrictor, which means it causes blood vessels to narrow temporarily.

In contrast, pump products like citrulline, betaine, taurine, and agmatine, often added to pre-workout formulas, are vasodilators, meaning they cause blood vessels to widen (the opposite of caffeine).

So, why is that a problem? Practically speaking, too much caffeine can negate the positive effects of pump products and reduce the overall effectiveness of a pre-workout formula.

Additionally, these opposite effects on blood vessels can lead to rapid changes in blood pressure that may lead to lightheadedness, heart palpitations, fatigue, and anxiety. 

As you can imagine, these are not things you want to experience, especially during a demanding workout.

While writing this article, we contacted Korbin from 4 Gauge because we noticed that their pre-workout is marketed for better blood flow (pump) and energy without jitters, and we wanted to hear their take. 

Here’s what he said:

“We only put 150 mg of Caffeine in 4 Gauge because the only real reason people take pre-workout, whether they know this or not, is to get vasodilation (blood flow) and some energy for the gym.

Caffeine acts as a vasoconstrictor when taken in high quantities, which defeats the purpose of taking a pre-workout in the first place. 

Adding an absurd amount of caffeine to 4 Gauge would not be beneficial to our product. We only have 150 mg of caffeine because it’s the right thing to do.”

If you’re taking a pre-workout product with a high caffeine content that’s causing you to feel sick, then consider switching to a product with a lower dose of caffeine.

Personalizing Your Pre-Workout (5 Tips)

To personalize your pre-workout to your specific needs, consider the following five tips:

Tip #1: Do a Trial Run

Let’s say you want to start taking a pre-workout but are unsure of your caffeine tolerance. In this case, starting small with a trial run is best.

Start with 80-100 mg of caffeine an hour before training. This dose would be below the recommended 3 mg per kilogram of body weight, even for smaller females, so you shouldn’t experience any adverse effects.

Write down subjective factors like your mood, energy levels, and motivation. Also, log your workout performance and see if there is a noticeable improvement in strength, power, endurance, or total work done.

Continue experimenting with dosages in the same manner until you find the dose that reaps the most benefits without side effects.

Tip #2: Choose An Appropriate Product

Examine the caffeine content of the pre-workout you want to take to help you pick the most appropriate product for your needs.

For example, let’s say that 100 mg of caffeine provides a noticeable boost in performance without side effects and without affecting your sleep later that night.

In this case, consider a pre-workout like Ghost Legend, as it offers 125 mg of caffeine per serving. I’ve broken down the caffeine content of 15 popular pre-workout products below.

Tip #3: Increase Doses Gradually, As Needed

When it comes to caffeine, slow and steady wins the race. Don’t immediately jump to high doses, especially if you’re not a habitual caffeine consumer. 

Take the minimum effective dose one hour before training and only increase it if the positive effects diminish over time.

For instance, let’s say your pre-workout has 125 mg of caffeine per scoop, so you start with approximately ¾ of a serving. Over time, you can work up to one level scoop (125 mg) and then 1.5 scoops (185-190 mg) as needed.

Tip #4: Try Dosing Based on Body Weight

As you increase your caffeine content, be mindful of potential side effects, such as anxiety, jitters, or heart palpitations.

If you haven’t experienced any side effects, consider dosing based on body weight using the 3 to 6 mg per kilogram of body weight recommendation.

For example, if you weigh 70 kilograms (154 lbs), that would be 210 to 420 mg of caffeine.

I recommend starting at the lower end of this range and not exceeding 400 mg. As mentioned above, this is the recommended safe upper limit the FDA sets and should not be exceeded regularly (or at all).

Tip #5: Don’t Forget to Cycle Caffeine

As a stimulant, caffeine’s effects gradually diminish, forcing you to take larger doses to experience the same benefits as before.

One way to tackle this and keep your caffeine intake under control is to cycle your consumption.

One example is consuming caffeine for three weeks and taking a week off. 

Cycling on and off caffeine slows the rate at which your body builds a tolerance, allowing you to continue enjoying the benefits at relatively low doses.

Another option is to consume caffeine before training and avoid it the rest of the day, providing similar benefits to cycling.

Another strategy is to save your pre-workout for your most challenging workouts (say, leg day) and to skip it or opt for a stim-free version for all other workouts.

Caffeine Content of 15 Popular Brands

The following table summarizes the caffeine dose per serving of 15 popular pre-workout supplements, ranked from highest to lowest:

Frequently Asked Questions

Can you build a tolerance to caffeine in pre-workouts?

Caffeine is a stimulant, and your body gradually builds a tolerance, depending on how frequently you consume it and what doses you take.

Are there any long-term effects of regular caffeine use in pre-workouts?

No evidence suggests regular caffeine consumption from pre-workouts or other products has adverse long-term effects.

Is more caffeine in pre-workouts better for performance?

Not necessarily. While caffeine can be beneficial, it can also temporarily narrow blood vessels, negating the positive effects of pump ingredients like citrulline malate.

What To Read Next

• Caffeine Pills vs Pre-Workout – Which Is Better?

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