Energy supplements for athletes: caffeine, carbohydrates & performance science

More energy when your training demands it

You know those days: your mind is ready, but your body struggles to get going. This is exactly where energy supplements can be a practical addition. They provide selected ingredients such as caffeine or carbohydrates in a form that can be used easily around your training.

The foundation remains important: sufficient sleep, a balanced diet and a sensibly structured training plan. Supplements do not replace this foundation—but they can help you shape your routine more purposefully.

Caffeine: more focus, less perceived fatigue

Caffeine is one of the most popular pre-workout aids—and for good reason. Used correctly, it can help you feel more alert, maintain your attention and perceive demanding sessions as slightly easier.

Caffeine may support the following during training:

• Greater alertness and concentration
• A lower perception of fatigue during intense sessions
• Endurance and readiness to perform—depending on the sport and the individual
• A focused start to your workout

More is not automatically better. Everyone responds differently to caffeine. It is therefore better to start cautiously, observe your tolerance and bear in mind that taking it late may affect your sleep.

• Guest et al. (2021)—Caffeine and athletic performance – Further scientific context on effects, dosage and individual differences.

Carbohydrates: fuel for long sessions

When your training lasts longer or becomes particularly intense, carbohydrates are an important source of energy. They help conserve your available energy stores and maintain your performance level more effectively throughout the session.

How to use carbohydrates sensibly:

• Before training: plan a well-tolerated, carbohydrate-rich meal
• During longer sessions: aim for approximately 30–60 g per hour depending on duration and intensity
• For very long endurance sessions: test higher amounts gradually during training
• Always consider individual tolerance and adequate fluid intake

The best plan is one your body tolerates. Therefore, test your strategy during training—not for the first time on competition day.

• Burke et al. (2011)—Carbohydrates for training and competition – Practical recommendations on carbohydrate intake before and during exercise.

BCAAs: supplement sensibly instead of consuming blindly

BCAAs—leucine, isoleucine and valine—are essential amino acids and are frequently promoted for use around training. They can make a small contribution to recovery after demanding sessions. However, they are not a miracle solution for greater muscle mass or performance.

What really matters:

• An adequate total amount of protein throughout the day
• Complete protein sources containing all essential amino acids
• Energy intake appropriate for your goal
• Consistent training and sufficient recovery

If your protein intake is already well established, isolated BCAAs usually provide no decisive additional benefit. Therefore, consider them an optional addition—not the foundation of your sports nutrition.

• Salem et al. (2024)—BCAAs and post-workout recovery – Overview of muscle soreness, recovery and performance.
• Jäger et al. (2017)—Protein and training – Context on protein quality and essential amino acids.

FitLine Activize: integrate energy easily

Would you like to keep your energy routine straightforward? FitLine Activize Oxyplus combines caffeine with selected vitamins and can be integrated flexibly into an active lifestyle.

Particularly practical: you can plan its use to suit your daily schedule—for example, before an early training session or during a period when concentration and readiness to perform are required.

• Practical preparation for use on the go and at home
• Caffeine for greater alertness and attention
• Selected vitamins to supplement your daily diet
• Easy to integrate into an existing sports and nutrition routine

Always follow the current product labelling and recommended daily serving. Activize contains caffeine and, according to the manufacturer, is not recommended for children or pregnant women. NTC® is FitLine’s proprietary concept; the specific formulation, your goals and your personal tolerance are the main factors when making your choice.

• FitLine—Activize Oxyplus – Official product information on formulation, caffeine and directions for use.