How Caffeine Effects Perfomance: All You Need To Know

How Caffeine Effects Perfomance: All You Need To Know

With over 19,000 studies examining the positive and negative effects of caffeine on the human body, it’s probably fair to say that you’ve heard a few of these opinions and are now asking the question… should I have that second morning espresso?

To help you get a better understanding, this article looks at the effects of caffeine on the human body and it’s use in athletic performance.

Caffeine and the Human Body

Caffeine is well absorbed into the body via the stomach and small intestine, with blood levels peaking about 45-60 minutes after ingestion.

Once in the blood stream caffeine has a number of physiological effects on the body. These include brain stimulation, increases in blood pressure, heart rate and stomach acid, as well as the break-down of fat stores.

These effects can last anywhere from a three to twelve hours. However, after 4 or 5 days of regular caffeine ingestion your body will begin to build a tolerance and you may not see any significant changes in the effects listed above.


Caffeine and Athletic Performance

Even with the extensive studies that have been conducted around the ergogenic effects of caffeine on muscle metabolism and endurance exercise, there are still some aspects of its function that cannot be fully explained.

Here however, is what we do know:


When we train in the gym or perform any form of endurance sport muscle exhaustion occurs when Glycogen, the primary source of fuel, is depleted. The body then resorts to the secondary, more abundant source – fat!

When we add caffeine to the mix the body begins to metabolise fat, stimulating the release of free fatty acids into the blood steam. The working muscles use this extra fat as energy in early exercise. Sparing muscle glycogen for later in your workout or exercise when you are really beginning to fatigue.


Although quite subjective, a number of studies have been conducted around caffeine and rating of perceived exertion (RPE). These tests involved a number of athletes being asked to judge their efforts during exercise, with half of the group ingesting caffeine prior and the other half a placebo.

Results indicated that the athletes using caffeine had significantly lower RPE’s and showed less signs of fatigue.

How much Caffeine do you need?

Research has indicated that a 3-6mg of caffeine per kg of bodyweight is optimum for an ergogenic effect. For example, a 70kg athlete would need to ingest 210 – 420mg prior to exercise.

Studies show a caffeine intake of 9+ mg per kg of body weight, can lead to an increase in side effects such as headache, jitteriness, nervousness, insomnia, dizziness, and gastrointestinal distress. All of which can have a detrimental effect on performance.

In our experience many athletes can experience these side effects at lower doses, so we recommend staying below around 3 – 4 mg per kg of body weight unless you are and experienced caffeine user.


Best Source of Caffeine

As you may have guessed the most common place people look for their caffeine hit is a cup of coffee. On average a single shot espresso (44ml) has 77mg of caffeine.

Based on what we’ve already discussed here, that means to get an ergogenic effect from coffee alone, you would need to drink at least five espressi before you workout. Therefore, making it an ineffective way to boost performance.

This is where we see the importance of a good quality pre-workout supplement. Your pre-workout can not only provide you with the desired amount of caffeine in a single serve, but should also contain ingredients such as Beta-Alanine and L-Tyrosine for mental focus. Along with Citrulline Malate and Betaine Anhydrous for increased Nitric Oxide production and skin bursting pumps.


Caffeine Safety

As we’ve mentioned, Caffeine is very well studied and a lot of Safety Data is available. In general dosages up to around 400mg per day are well tolerated with few side effects and no long term health issues, although athletes who are caffeine sensitive need to adjust dosages accordingly.


Getting the most out of Caffeine Supplementation

Athletes can become de-sensitized to caffeine if they consume a significant amount every day. We recommend cycling your caffeine intake down on non-training days or days when you don’t need to go all out. For most people this means cutting back your coffee intake to one or two cups per day. Then on the days you really need a caffeine kick your body will be much more receptive to a higher dose and you will gain a much greater benefit.



In answer to your question – Yes! Have that second coffee! But in order to meet the required amount of caffeine needed to increase athletic performance, look for a pre-workout with a caffeine dosage of 300-350mg. By ingesting this amount of caffeine 20 to 30 minutes prior to exercise you will start to feel its benefits at a point in your workout where you would usually start to fatigue.

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