The Benefits Of Pre-Workout Caffeine


There are two types of people out there: the ones who can’t even consider starting their day without a cup of joe, and those bright-eyed souls who manage to kickstart their mornings without the help of coffee.

Regardless of which camp you belong to, you might be missing out on some pretty cool perks of having caffeine before your workout. And it could just be the game-changer that turns you into a coffee lover, if you haven’t already hopped on that bandwagon!

But hang on before chugging down a strong brew first thing in the morning if you’re not used to caffeinated wake-ups. Getting those benefits is all about finding the right dosage and timing.

So keep reading as we cover how to nail that ideal caffeine boost to amp up your runs, whether you’re hitting the road or the trail.

What Is Caffeine?

Caffeine is a chemical that’s found naturally in several plants. Yes, it’s most common in coffee, but it’s also present in over 60 other things!

It’s a stimulant, which means it increases brain and central nervous system activity by boosting the speed of messages between the brain and the body.

While it can have negative side effects if not used carefully, using it as a pre-workout is an excellent idea, thanks to how natural it is compared to other lab-created pre-workout mixes or pills.

How Caffeine Works

Caffeine has more effects on the body than just making you feel more awake! It works on the cardiovascular, respiratory, and nervous systems.

The biggest effect it has is that it blocks adenosine receptors in the body. Adenosine is a chemical that promotes sleep. Caffeine successfully blocks this chemical from reaching adenosine receptors, so your grogginess rapidly disappears.

A side effect of this sleep-blocking is that it affects the release of other chemicals in the brain, the most notable of which is that your brain will be stimulated to produce more norepinephrine, resulting in a performance-enhancing effect.

Caffeine also promotes thermogenesis—heat production—which may help to speed up your daily energy metabolism. Thanks to its antioxidant content, caffeine can also give you a great immune system boost.

Other effects include dilating the blood vessels and making your heart beat faster—which raises blood pressure temporarily and makes breathing easier. It also stimulates kidney and bowel functions, and might even have pain-killing effects.

Keep in mind that this is how caffeine works if you take it alone, without anything else. When taken with other nutrients or supplements, caffeine may have slightly different effects.

Caffeine’s Impact on Running Performance

So now you know what caffeine does to your body, but how does that affect your running? Thanks to the effects of caffeine on your system, when you drink a cup of strong coffee before you run, it primes your body for better performance.

When your heart is pumping harder, and your blood vessels are open wider, oxygen-rich blood gets to the muscle faster, fueling them so you can run faster and farther before becoming fatigued.

Its pain-killing effects might also help your muscles hold out for longer before they start to feel sore, which can help during your run but also reduce DOMS.

As long as you stick to your rest days, you can expect faster recovery as well, thanks to increased circulation and reduced inflammation. Better recovery equals better performance in subsequent runs.

Research also suggests that caffeine’s mental sharpness is a large part of the performance benefit, keeping you focused and determined for longer.

Plus, you’ll be less likely to get sick during the change of season thanks to caffeine’s immune-boosting properties. Less taking time off due to feeling under the weather!

Benefits of Caffeine as a Pre-Workout Aid

Choosing caffeine as your pre-workout has a bunch of benefits. Not only is it fairly affordable—especially in comparison to other pre-workout supplements—but it’s quite easily accessible. Here are some other benefits you can expect:

Increased Alertness and Focus

You can use that morning coffee buzz to help you drag yourself out of bed, but it can also boost your alertness on your run, keeping you more focused.

According to a study, caffeine also increases something called your “readiness to invest effort,” which means along with focus and alertness, you’re likely to be putting in more effort than you even realize.

Reduced Perceived Effort

When you’re running at the same general level of effort as you usually do but your cardiovascular system is boosted, you’ll feel like your run is easier than usual.

You’ll be able to run farther and probably faster for what feels like the same amount of effort as previous slower runs. It could be down to a combination of physical effects of adenosine-blocking and endorphins that caffeine helps to release—the same stuff that gives you that runner’s high!

Enhanced Endurance

Because your muscles are getting more oxygen and nutrients during your run, you’ll have better endurance than usual as this delays fatigue from setting in.

Along with increased focus and the reduced perception of effort, you’ll most likely be able to push harder without feeling like you’re overdoing it. With caffeine in your system, you’ll be best positioned to hit a new PR!

Enhances Your Body’s Use of Fat As a Fuel

Interestingly, ingesting caffeine before or during a run can help your body to burn fat more efficiently, so there’s a chance that choosing caffeine as your pre-workout could have minor weight-loss effects.

Research suggests that caffeine spikes the amount of fatty acids in your bloodstream, which makes it more readily available for your body to use during a run for fuel. It’s been researched more in the case of marathon runners, but could have implications for other runners, too.

This effect is enhanced when you take your caffeine with a carbohydrate source, like having coffee with a snack or with a sports drink.

Improved Reaction Time

That extra alertness and focus also makes your reaction time quicker than usual. You’ll be able to skirt around potential hazards like uneven ground, potholes, or unexpected visitors in your path with much more ease.

This quicker reaction time can also go a long way towards reducing the number of injuries you suffer.

Improved Blood Flow

As caffeine widens your veins and arteries as well as increases blood pressure just slightly, you can look forward to more efficient pumping of blood around the body.

This means your muscles will get oxygen and nutrients faster than usual, so it’s handy for both performance and recovery.

Improved Mood and Motivation

The stimulant effect of caffeine could boost your mood as well. Some of us know this all too well—our mornings don’t start well if we don’t have our coffee! But it can help your run as well, by providing a touch more motivation when you might otherwise be feeling less excited to get out and do your scheduled run.

Timing Is Key: When to Consume Caffeine Before a Run

About 99 percent of the caffeine you consume is absorbed by the body within 45 minutes of taking it. So, if you really want to get the best effects from your pre-workout caffeine drink, it’s a good idea to take it within that time.

Of course, it also depends on how much you drink and how well your body responds to it. You might need to experiment to find that sweet spot for you, but around 30 minutes before your run should be optimal for many people.

While pre-workout caffeine will help you start with a caffeinated pep in your step, some runners prefer to delay their caffeine intake until mid-run, to give them a boost when they start to feel tired.

Obviously, this is a better strategy for long runs. If you’re planning on taking an hour-long run, taking caffeine mid-run won’t help because your body will only absorb it when your run ends.

How Much Caffeine Should You Have?

Caffeine is one of the most-researched stimulants on the planet. Studies show that the optimal dosage for most people is 6 mg of caffeine per kilogram of body weight.

The best way to figure this out is to first work out your weight in kilograms—multiply your weight in pounds by 0.45359237. Then multiply that by 6 to determine your ideal milligram dosage.

That might be tricky, but once you’ve got the number, it’s as simple as working out how much of any given caffeine source you should have based on how much caffeine is in your chosen coffee.

Keep in mind that you might need to adjust it as you lose weight so you don’t accidentally overdose yourself.

If 6 mg per kilo gives you the jitters or causes stomach upset, you can safely down it to 4 or 5 mg per kilogram. Research indicates that 3 mg or less has little to no effect, so don’t go lower than that.

How Much Caffeine is In a Cup of Coffee?

A typical espresso shot contains 63 mg of caffeine, and most regular 8 oz. cups of brewed coffee contain 80 to 100 mg. But it’s very subjective—the exact amount depends on many things, like the type of coffee and how it’s brewed.

One cup of instant coffee has much less caffeine—about the same amount as a single shot of espresso. So the amount of coffee you’d need to drink to hit your 6 mg/kg really depends on what you’re drinking!

You should know, though, that one cup of coffee isn’t likely to be enough for most runners if you want to get the best benefits from the caffeine content.

It’s not practical to drink multiple cups of coffee before going for a run, though. So you might need to do some digging to find highly-caffeinated coffee or consider other ways of getting your caffeine fix.

Factors to Consider for Your Own Caffeine Dosage

Now you know that 6 mg/kg is the optimal dosage. But before you leap right into it at that amount, take some time to consider your own body, health, and needs. Assess:

  • Your tolerance to coffee/caffeine
  • Any gastrointestinal issues
  • Health conditions

If you already know that you get jittery from one cup of medium-strong coffee, then less is probably more for you. Also, if you’re prone to gastrointestinal upset, then be cautious because caffeine can stimulate things down there.

Lastly, if you have any health conditions, we recommend consulting your doctor before you start taking caffeine as a pre-workout. They’ll be able to advise you on whether or not it could be dangerous based on your health.

The Potential Side Effects of Caffeine

Caffeine can have nasty side effects if not used properly. Here’s what you might find yourself dealing with if you’re taking too much caffeine for your system to handle:

Stomach Issues

Strong coffee can stimulate the bowels, which means whatever’s in there will get a push to come out. You might experience a grumbling, gurgling stomach, cramps, or reflux. High doses of caffeine can have a laxative effect, so in some cases, diarrhea is possible.

If you’re drinking your coffee with dairy products like milk or cream, these effects can be exacerbated thanks to the combination of caffeine and lactose. Start slow to make sure your stomach can handle the caffeine you’re giving it.

More Frequent Urination

Caffeine is a mild diuretic, and if you’re consuming in liquid form, you’re going to need to go to the bathroom sooner and more often than you might usually. If you’re out running somewhere without bathrooms, you might need to go offroad.

This is a more common issue in runners new to caffeine—once your body is used to it, you should adapt and not have to run to the bathroom quite as often.

Jitters (and Crashes)

The stimulating effects of caffeine can be too much for those who aren’t used to it, or just for some people who might be more sensitive to caffeine than others. The “jitters” can make you feel shaky and unfocused, making life uncomfortable for a while until it wears off.

Heart Palpitations

Too much caffeine can also make your heart feel like it’s beating harder or faster than usual. This can be a disconcerting feeling and might even spike feelings of panic.

It typically diminishes as you get more used to caffeine, but you should gradually lower your dosage and build your way up.


The raised blood pressure that comes with caffeine can lead to “blood pressure headaches”—a pounding headache that can knock you down. Once the caffeine has worked its way through your body, it should subside.

Who Should Use Caffeine for Their Run?

Runners who already know they can tolerate caffeine should definitely give it a try. It’s also a good option for runners who don’t want to use chemical-laden pre-workouts, which may contain fillers or synthetic chemicals.

You can safely assume that caffeine will work for you if you’re generally healthy, have no heart problems, and have a strong stomach.

Who Shouldn’t Opt For Caffeine?

Runners who know they don’t handle caffeine well can try it at low doses but might be better off choosing something else. If you’re prone to gastrointestinal issues, it might have worse effects that negate the positive ones.

Caffeine can also mess with your body’s iron absorption, so if you struggle with anemia, you should avoid using caffeine as your pre-workout.

Beyond Coffee: Alternative Sources of Caffeine

Coffee isn’t the only way to get your caffeine fix. If you’re not a fan, you can find caffeine supplements in various forms, including:

  • Energy gels
  • Energy chews
  • Caffeine tablets
  • Caffeinated sports drinks

Check carefully to see how much caffeine you’re getting per serving. It’s also important to note that when it comes to gels and chews, usually only certain flavors within a brand are caffeinated, so your choices might be limited.

Gels, chews, and drinks also usually contain carbs, whereas caffeine tablets are usually pure caffeine.

Myths About Caffeine and Running

Are you scared to try caffeine because of what you’ve heard? Here are some caffeine myths, busted.

Myth 1: Caffeine Dehydrates You

It’s true that caffeine is a mild diuretic, but you need to take a lotttt of it to have a negative effect. As long as you’re drinking enough during your run—your usual amount—you can safely run without any harmful dehydrating effects.

Myth 2: Caffeine Can Replace Proper Training

Caffeine isn’t a magic bullet. You can’t do half a job when you’re training and expect caffeine to carry you the rest of the way.

While it does improve performance if taken in the correct doses, research shows that the improvement tends to hover around 2.5 percent, so YOU still have to be the hero of your run.

Myth 3: More Caffeine Is Always Better

Stick to your 4 to 6 mg of caffeine per kilogram of body weight. There’s nothing to be gained by exceeding it—you’re only putting yourself more at risk of jitters, headaches, and stomach issues.

Myth 4: Coffee Hampers Your Recovery

The vasodilation effects of caffeine can help the blood to circulate faster, bringing much-needed oxygen and nutrients to your muscles as they recover. Plus, the antioxidant properties can positively affect you and help you recover faster.

Photo of author


Ben is an avid road and trail runner, and has completed multiple marathons and ultras. A former running store owner, he now shares his knowledge and experience writing these articles.