Caffeine in Athletes

Caffeine, the main active component of coffee, is one of the most widely consumed psychoactive substances in the world. It is commonly used both in daily life and in sports, where it is valued for its stimulating effects. But what are its actual impacts on the body? What is the right dosage for athletes? Are there alternatives to coffee?

1. Impact of Caffeine on the Body

a. Stimulation of the Nervous System

This Natural stimulant primarily works by blocking adenosine receptors, For athletes, the recommended caffeine dose to optimize performance without compromising health is between 3 and 6 mg per kilogram of body weight per day. For example, for a person weighing 70 kg, this corresponds to between 210 and 420 mg of caffeine (roughly 2 to 4 cups of coffee) per day.a molecule that promotes relaxation and drowsiness. The result: an increased sense of alertness and concentration.

b. Improved Endurance and Reduced Perception of Effort

Studies have shown that caffeine can enhance endurance by promoting the use of fatty acids as an energy source, thus preserving glycogen stores—a form of carbohydrate storage in the muscles and liver used for energy during a workout. Additionally, it reduces the perception of fatigue, allowing for prolonged physical efforts and longer Kinomap sessions.

c. Possible Side Effects

Despite its benefits, caffeine can cause undesirable effects that vary depending on individual sensitivity and the amount consumed. The most common side effects include:

• Nervousness and anxiety: Excessive consumption can lead to restlessness, irritability, and heart palpitations.

• Sleep disturbances: Since caffeine can remain active in your body for several hours, it may interfere with falling asleep and reduce sleep quality, affecting recovery—especially when consumed later in the day.

• Gastrointestinal issues: Some people may experience nausea, acid reflux, or abdominal pain after consuming coffee.

• Tremors and reduced precision (at high doses).

• Increased heart rate (tachycardia).

2. Where Can You Find Caffeine?

Caffeine is naturally present in more than 60 plants and can be found in many everyday foods and beverages.

a. Main Sources:

• Coffee: The primary source, containing around 80 to 120 mg per cup.

• Tea (green, black, white): Contains between 20 and 60 mg per cup, depending on the variety and brewing time.

• Energy drinks: Between 50 and 150 mg per can.

• Sodas: Around 30 to 50 mg per can.

• Chocolate and cocoa: Dark chocolate is richer in caffeine (20 to 30 mg per 50 g) than milk chocolate.

• Certain medications: Especially those used for migraines or drowsiness.

b. What is the Recommended Daily Caffeine Dose?

For athletes, the recommended caffeine dose to optimize performance without compromising health is between 3 and 6 mg per kilogram of body weight per day. For example, for a person weighing 70 kg, this corresponds to between 210 and 420 mg of caffeine (roughly 2 to 4 cups of coffee) per day.

It is advised not to exceed 400 mg of caffeine per day, according to general recommendations for adults. Going beyond this dose can trigger the previously mentioned side effects and negatively impact both performance and health. It’s best to test your tolerance outside of competitions.

3. The Benefits of Caffeine in Endurance Sports

Disciplines such as running, cycling, swimming, and rowing particularly benefit from caffeine for its effects on endurance and fatigue reduction.

Studies show that a moderate dose of caffeine (about 3 mg/kg of body weight) taken about an hour before exercise can improve endurance performance by 2 to 5%.

It is also possible to consume caffeine in the form of gels or energy drinks, taken in smaller doses during training, which helps maintain its stimulating effects throughout the effort.

4. Alternatives to Coffee

While coffee is a popular source of caffeine, many people seek alternatives that offer similar effects without the possible drawbacks of coffee (such as gastric acidity or bitter taste).

Several interesting options are available:

a. Green Tea and Mate

Both contain caffeine (called theine in tea), but in moderate amounts, providing a gentler and more sustained stimulation.
Green tea is rich in antioxidants, which promote muscle recovery and reduce inflammation after exercise.
Mate, widely used in South America, combines caffeine, antioxidants, and essential minerals, helping both mental alertness and physical endurance.

b. Natural Energy Drinks

After a workout, certain fruit juices, such as beetroot or pomegranate juice, are also used by athletes as recovery drinks (see article “What to Eat After a Workout”). They improve blood circulation and endurance without containing caffeine.

When consumed in moderation, caffeine can be a valuable ally by enhancing endurance, concentration, and reducing the perception of effort. However, it is essential to understand your own tolerance and avoid excessive intake, especially if you have cardiovascular issues.

As always, it’s recommended to test different options outside of competitions to assess your needs and preferences!

Chloé Masson
Nutrition Project Manager
chloemasson.nutrition@gmail.com

See previous nutrition articles :
ANIMAL PROTEINS AND VEGETABLE PROTEINS
EATING WELL AFTER A WORKOUT