Our body is a true source of energy – whether we are lazing around or being physically active. But how do we turn food into fuel for our activities? And what happens inside when we exercise? Why do we get out of breath and suddenly feel heavy legs when we exert ourselves physically? Is it due to lactate, i.e. lactic acid, or do other factors play a role? In this blog post, we will get to the bottom of these questions and shed light on how our body works and responds to exertion. Let’s dive together into the fascinating world of energy production and performance enhancement!
\nWhen you start eating, your body immediately begins converting the food you consume into energy. This energy is needed to maintain your bodily functions and support you during physical activities such as sports. During digestion, carbohydrates are broken down into glucose, proteins into amino acids, and fats into fatty acids. These components are then converted into ATP, which serves as a universal energy carrier.
Depending on the type of sport and the intensity of the activity, your body uses two different energy sources, which it draws on according to need and efficiency in order to provide you with the energy required: energy production without oxygen (anaerobic) and energy production with oxygen (aerobic).
\n![\"Glowing](\"/wp-content/uploads/2025/11/zitat-artikel-blog_sport.jpg\")
ATP: The energy source of our cells
\n\n\n\nAdenosine triphosphate, also known as ATP, is a chemical compound that is present and produced in all cells of living organisms. It serves as an energy source for various biological processes such as movement, vital functions (such as breathing and heartbeat), cognitive processes, and molecular processes such as the transport of substances.
\n“A healthy diet fills your body with energy and nutrients. Imagine your cells smiling at you and saying: Thank you!” Karen Salmansohn
\nTo develop an understanding of what your body needs and how you can supply it with energy in the best possible way, it is crucial to know how anaerobic and aerobic energy metabolism work.
It is important to note that energy production never occurs through just one system, but always takes place in parallel. Which metabolic process contributes the largest share to energy production depends largely on the type of sport, more precisely on the duration and intensity of the exertion.
\nEnergy production outside the mitochondria in the cytoplasm enables the body to access a special energy store during very intense and short activities of up to 10 seconds (creatine kinase). This store includes small amounts of ATP in the muscles as well as creatine phosphate, which is mainly produced in the liver and transported to the muscles via the blood. Since no oxygen is required for this process, the body can provide energy very quickly, but only for a short time. This type of energy production is ideal for activities and sports that are performed quickly and powerfully within a short period of time, such as weightlifting, sprints, throwing, jumping, or lifting heavy loads.
During physical exertion that lasts longer than 10 seconds but no more than 90 seconds, such as HIIT workouts, interval training, or 400 m sprints, the body obtains its main energy from stored carbohydrates. More precisely, from their storage form, “glycogen,” which is converted into ATP and is known as (anaerobic) “glycolysis.”
This process takes place without oxygen and provides energy quickly, but only for a short time, because it produces what is known as lactic acid (lactate), which is associated with fatigue in sports. Contrary to popular belief, however, lactate is not responsible for the burning sensation during intense exercise sessions; rather, it is positive hydrogen ions that form during high exertion. Nevertheless, lactate concentration provides information about how exhausted a person is.
\nEnergy supply takes place in the mitochondria, the powerhouses of our cells.
In contrast to the anaerobic process, during exertion lasting from approx. 3 minutes onward, the body uses this energy store and glycolysis additionally uses oxygen to produce ATP (aerobic glycolysis). Although this process takes longer because the oxygen has to travel from the lungs to the muscles, energy can be provided for longer and is therefore ideal for sports such as swimming, tennis, football, or longer training sessions. The disadvantage, however, is that our glycogen stores eventually become depleted, and we then have to reduce the training intensity.
When this is the case, our body next draws on its fat reserves with the help of oxygen. This process is called lipolysis, and ATP is obtained from our stored fats. Since this takes a very long time, it also means that we can only train with very low exertion, but we also have an almost inexhaustible supply of fat and can maintain physical exertion over a very long period of time.
\n![\"Runner](\"/wp-content/uploads/2025/11/zitat-artikel-blog_training.jpg\")
When should you train anaerobically and when aerobically?
\n\n\n\nTraining without oxygen is advisable if you want to achieve quick results, increase your muscle mass, improve fat burning, and determine your anaerobic threshold.
Training with oxygen makes sense if you need slow and efficient energy produ"
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"answer": "The body converts carbohydrates, fats, and proteins from food into ATP, the main energy carrier used by cells for movement, vital functions, and physical performance.",
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"answer": "ATP, or adenosine triphosphate, is the universal energy source of cells. Muscles use ATP to contract, making it essential for strength, endurance, and overall athletic performance.",
"question": "What is ATP and why is it important for sports performance?"
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"answer": "Anaerobic metabolism produces energy quickly without oxygen for short, intense efforts. Aerobic metabolism uses oxygen to provide energy more slowly but for longer-duration activities.",
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"answer": "Anaerobic energy production is used during very intense, short activities such as sprinting, weightlifting, jumping, throwing, HIIT workouts, and interval training.",
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"answer": "Aerobic training is beneficial for endurance, cardiovascular health, long-term fat metabolism, and activities lasting several minutes or more, such as swimming, football, tennis, and longer workouts.",
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"answer": "Contrary to common belief, lactate itself is not the main cause of the burning sensation. The burn is mainly linked to hydrogen ions that accumulate during high exertion.",
"question": "Is lactate responsible for burning muscles during intense exercise?"
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"answer": "Athletes can support performance with gradual training progression, a mix of endurance and strength work, warm-ups and cool-downs, sufficient protein, balanced nutrition, and acid-base support when needed.",
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