Should You Consume Caffeine During Training and Races?

It’s rare to find someone who doesn’t consume caffeine in any form. There are numerous myths surrounding its benefits and harms.

While some theories suggest that this substance can be consumed without any harm to one’s health, others scare people with the possibility of strong negative side effects and recommend avoiding caffeine altogether.

Both sides of the argument hold some truth. Caffeine can energize some people, have little to no effect on others, and be contraindicated for some.

In this article, we’ll explore what this substance is, how it impacts the body, and whether caffeine is truly effective for enhancing performance in competitions. Most importantly, we’ll discuss how and in what quantities runners should consume caffeine to improve their race results.

Contents

What Caffeine Is and How It Works

Caffeine is a chemical substance found in the leaves and seeds of plants, and can also be synthesized artificially.

Due to its impact on the central nervous system, caffeine is commonly used as a stimulant to enhance alertness and focus. It is also utilized for medical purposes, including as an ingredient in painkillers.

Athletes actively consume caffeine-containing products during races and training sessions due to their stimulating properties.

For most people, caffeine acts as a stimulant, leading to increased productivity, alertness, and energy. It also helps combat sleepiness and increase motivation. Additionally, caffeine has negligible calorie content (excluding flavored lattes).

Should You Consume Caffeine During Training Sessions and Races? — Caffeine causes excitement, boosts mood, and provides a surge of strength and energy for many people. Image by rawpixel.com on Freepik

How Caffeine Affects the Body

When we consume products that contain caffeine, where does the energy come from? The human body can only derive energy from adenosine triphosphate (ATP). Our cells contain organelles called mitochondria, which act as energy stations. ATP is constantly being broken down and resynthesized within these mitochondria, releasing energy that powers all of the body’s vital activities.

To put it simply, ATP breaks down into adenosine diphosphate (ADP) and phosphate during a cycle of chemical reactions. Then, ADP breaks down into adenosine monophosphate (AMP) and phosphate, and so on. When these bonds break, energy is released, which is used to sustain all processes in the body.

Adenosine, a byproduct of ATP breakdown, exits the cell through specific channels and binds to purinergic receptors. These receptors interpret the adenosine signal as an indication of fatigue, signaling that the body’s ATP stores have been depleted and rest is necessary to replenish energy reserves.

However, caffeine molecules block these receptors, preventing the signal of fatigue from passing through.

Caffeine itself does not have any energy value and does not participate in the resynthesis of ATP. Instead, it acts as a stimulant by blocking the transmission of the fatigue signal.

Why Caffeine Affects People Differently

The effect of caffeine is not as straightforward as you might expect. Some people’s nervous systems have unique characteristics that can lead to caffeine having either no effect at all or causing drowsiness and sluggishness. But why does this happen?

The nervous system has two opposing properties – excitation and inhibition. These properties are conveyed from one neuron to another by neurotransmitters, which are specialized substances that facilitate the transmission of nerve impulses.

There exist nerve cells that produce the primary excitatory neurotransmitter – glutamate, as well as nerve cells that produce the primary inhibitory neurotransmitter – gamma-aminobutyric acid.

The distribution of the above-mentioned purinergic receptors across cells can vary. When caffeine has an equal effect on cells (i.e., there is an equal distribution of these receptors among inhibitory and excitatory cells), the overall state of the nervous system remains unaffected. In everyday life, this biological process manifests as follows:

Most people have a higher concentration of purinergic receptors on cells that produce an excitatory neurotransmitter, resulting in coffee having a stimulating effect.
In one out of six people, the distribution of these receptors is equal, and coffee doesn’t have a noticeable stimulating effect. However, the subjective experience of heart and internal organ function may be different.
In one out of twenty people, inhibitory cells have a higher concentration of these receptors, causing caffeine to promote inhibition and induce drowsiness.

How Caffeine Affects Various Systems and Processes in the Body

Because the nervous system responds differently, there are conflicting studies on the consumption of caffeine-containing products, resulting in a significant variation in the safe dosage range.

Nevertheless, there are some general effects and commonalities that can be identified.

The effect of caffeine on the cardiovascular system

Receptors that are sensitive to adenosine, a byproduct of ATP breakdown, are found in both the walls of blood vessels and the heart. When adenosine accumulates, it sends a “fatigue signal” that lowers the heart rate.

Caffeine blocks adenosine receptors and prevents the heart from slowing down using the same mechanism described earlier.

Although in the past it was believed that this might cause arrhythmia, most modern studies have not confirmed this concern.

However, caffeine can raise blood pressure in those who consume it infrequently. This increase is not typically dangerous for people without cardiovascular disease, but hypertensive patients may experience a stronger reaction.

The effect of caffeine on the endocrine system

Evidence suggests that regularly consuming coffee in recommended doses can lower the risk of developing type 2 diabetes. While the mechanism behind this is not yet fully understood, some speculate that caffeine helps to increase adiponectin levels, a substance that can heighten cell sensitivity to insulin.

The effect of caffeine on digestion

The bitter taste of coffee stimulates the production of gastric juice, ultimately lowering its pH and increasing acidity.

Although consuming coffee on an empty stomach can potentially cause gastritis, caffeine’s effect on gastric motility is also utilized in pharmacology to treat pain syndromes. This is because it can enhance gastric motility, measured by pressure waves and propagating contractions in the transverse and descending colon, which can help alleviate pain and discomfort.

Сaffeine can speed up drug absorption and enhance pain relief by reducing the time needed for drugs to reach maximum concentration in the bloodstream.

Caffeine’s lipolytic effect

Many people note the fat-burning effect of caffeine. Moreover, it’s even included in the composition of many lipolytic products. However, it’s important to note that there’s no such thing as a miracle weight loss pill.

In the body, fat can’t be melted like it does in a frying pan. It’s utilized solely through chemical reactions that occur in the mitochondria to produce energy and resynthesize ATP. We can only influence the speed and duration of these processes.

As mentioned earlier, caffeine blocks the signal of fatigue, allowing physical activity to continue for longer periods, and during this time fat is still used as fuel.

Recommended Daily Caffeine Consumption Levels

The general recommendation is that healthy adults should not consume more than 400 mg of caffeine per day. For children, the recommended limit is 100 mg, while for pregnant women it’s 200 mg.

It’s important to consider both the caffeine we get from foods and drinks, as well as caffeine from sports supplements.

Caffeine is mainly found in various drinks. Interestingly, the substance itself has a bitter taste and is in the form of white or transparent crystals, in contrast to the dark color of coffee and tea.

Here’s a rough ranking of drinks based on their caffeine content:

Filtered coffee (6.8 fl oz / 200 ml) – 150 mg
Coffee brewed in a pot (6.8 fl oz / 200 ml) – 110 mg
Espresso (2 fl oz / 50 ml) – 60 mg
Cappuccino (6.8 fl oz / 200 ml) – 30-50 mg
Latte (6.8 fl oz / 200 ml) – 30 mg
Black tea (6.8 fl oz / 200 ml) – 30 mg
Green tea (6.8 fl oz / 200 ml) – 25 mg
Red Bull (8.5 fl oz / 250 ml) – 80 mg
Coca-Cola (12 fl oz / 330 ml) – 40 mg

Thus, you can drink 2-3 cups of coffee a day without putting your health at risk, as long as you don’t have any cardiovascular diseases or other direct contraindications.

Caffeine is also present in cocoa beans, which means it can be found in chocolate and chocolate desserts, but the amount is not significant enough to have a substantial effect on your daily caffeine intake.

Caffeine: Doping or Not?

It’s not surprising that endurance athletes use caffeine to combat fatigue during long-distance running, swimming, and cycling.

Currently, WADA does not consider caffeine to be doping. It’s classified as a “Stimulant” (S6) and included in the monitoring program (for 2023), but not prohibited.

However, from 1984 to 2006, it was on the list of banned substances. It was removed largely because some people lack the enzyme to metabolize caffeine. As a result, even after consuming just a couple of cups of coffee, such individuals can show a high concentration of caffeine in their analysis.

Additionally, it was challenging to determine whether an athlete consumed caffeine-containing drinks for pleasure or to enhance the performance results since the level of caffeine was measured through urine analysis.

Overall, although caffeine has a stimulating effect, it’s not substantial enough in normal doses to have a significant impact on athletic performance.

How and When to Take Caffeine During a Race

1. Determine the dosage

General recommendations suggest that caffeine intake should range between 3-6 mg per 2.20 lb / 1 kg of body weight per day, and a single dose should not exceed 200 mg.

If you prefer to take caffeine in the form of gels during a race, they can be categorized into three types based on their caffeine content:

Low-caffeine gels (up to 40 mg per serving)
Medium-caffeine gels (50-100 mg per serving)
High-caffeine gels (150 mg and above)

We will discuss how to consume them in more detail shortly.

2. Decide when to take caffeine

Some athletes prefer to consume it closer to the finish line, during the second half of a race, when their energy levels are already low. Others prefer to take it some time before the start.

However, a combination of the two approaches seems more logical. This is because it takes about 30-40 minutes for caffeine to take effect and be absorbed by the body. If caffeine is only taken toward the end of a race, it may not have enough time to work effectively.

Therefore, it makes sense to take caffeine before the start and then consume a maintenance dose approximately every hour. It’s important to ensure that you don’t exceed the maximum daily and single dose.

Similarly, the energizing effect of Coca-Cola, which some runners drink to boost their performance toward the end of a race, is greatly overestimated. Our brain primarily reacts to the sugar in it, which creates a “boosting effect.”

As there is little caffeine in the drink, its actual impact on our energy levels is minimal. Nevertheless, the drink can certainly boost your mood for some time because of the immediate placebo effect.

3. Decide in what form to consume caffeine

Because caffeine stimulates the digestive system, carbohydrates from gels combined with caffeine will be absorbed better. That’s why gels containing caffeine are a preferred option.

Before the start of a race, it’s recommended to consume gels with low caffeine content, as the body has not yet experienced fatigue, and the anticipation of a race itself provides energy. During the course, gels with low or medium caffeine content can be taken.

Consumption of gels with high caffeine content should be moderate as there is a risk of exceeding the daily caffeine limit and experiencing unpleasant consequences from a too-high single dose (for example, gels containing 300 mg of caffeine in a gel volume of 2 fl oz). Therefore, it’s recommended to avoid overusing gels with high doses of caffeine.

The main symptoms of caffeine overdose include

nausea, vomiting, diarrhea
restlessness, anxiety, panic
limb tremors, and in higher doses, seizures
headaches
ringing in the ears
disorder of consciousness
increased heart rate, arrhythmia
high blood pressure.

The optimal dosage, timing, and methods of caffeine intake should be determined individually, and not at the start of a race, but in advance during preparation. Nothing new should be introduced during a race, whether it be equipment or food, to avoid unpleasant surprises.

Since caffeine affects the nervous system, caffeine-containing gels should not be used in every training session to prevent developing a tolerance to caffeine. Moreover, to experience the actual effect of such gels during competitions, it’s advisable to refrain from consuming coffee or caffeine in any other form for a few weeks before a race (caffeine-free diet).

Conclusion

Caffeine has an invigorating effect on most people, providing a feeling of strength, energy, and mental clarity, while also enhancing concentration and productivity. This is because caffeine blocks receptors that transmit signals of fatigue to the brain.
The negative effects of caffeine, in general, and coffee, in particular, are greatly exaggerated – when consumed in reasonable doses, it does not cause a rise in blood pressure, tachycardia, dehydration, or other adverse effects.
The recommended daily intake is up to 400 mg of caffeine, and a single dose should not exceed 200 mg.
Caffeine-containing gels can indeed stimulate performance during long runs. To achieve this, it’s important to take them correctly: consume a small dose of caffeine 30-40 minutes before starting, and then a maintenance dose approximately once per hour. It may be possible to increase the single dose in the second half of a race, but care should be taken to ensure that the total dose does not exceed the maximum allowable amount.
Our bodies are different, and the reaction to caffeine may vary. Therefore, the scheme for taking gels with caffeine should be tailored individually, and it is advisable to do it during training rather than races to avoid any surprises at the start.

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