Fat burning vs. fat loss
Sports burn fat. This is true, of course, but not necessarily in the way you might think. To optimally lose body fat and define your body, it's important to understand the difference between fat burning and fat consumption. Contrary to the colloquial use of these terms as synonyms, they are strictly speaking two different concepts characterized by different metabolic states. So what is the difference? And how can you put this knowledge to work for you?
The breakdown of body fat has a single condition. This is a negative calorie balance at the end of the day or better the week or month. If you burn more calories than you consume or, conversely, consume less than you consume, your body must provide the missing energy from reserves. These reserves are mainly found in storage fat, so the body breaks down fat to provide the missing energy.
How exactly this calorie deficit is achieved is of secondary importance. You can either save calories through diet or increase your consumption through exercise. The larger the deficit, the more fat you lose. However, a deficit that is too large carries the risk of losing not only fat but also muscle mass and limiting other bodily functions. As a result, your training would also suffer and a main driver of fat loss would no longer function optimally. In practice, a deficit of 500 to 1000 Kcal per day has proven to be effective, whereby it strongly depends on how much fat you want to lose, how high your current calories are and how fast you want or need to lose weight.
Furthermore, it is equally secondary by which type of training you achieve your deficit. Whether it's weight training, cardio, walking or simply consuming fewer calories; as soon as you reach a negative energy balance in the medium and long term, you will lose body fat.
Fat burning, on the other hand, means that during exercise, i.e. during your workout, fat is used as an energy source. This succeeds especially at low intensities up to about 70 percent of the maximum heart rate. Therefore, the range from 60 to 70 percent of the maximum heart rate is often referred to as the fat burning zone. At higher intensities, the proportion of fat burned directly decreases very quickly and it is mainly carbohydrates that are burned.
If there is a negative calorie balance, fats are then consumed from the stores in the downstream phase. Both ways of energy supply (carbohydrates and fats) always run parallel. However, the higher the effort, the lower the proportion of fat burning and the higher the proportion of carbohydrate use. This is because fat can only be burned in the presence of oxygen, carbohydrate metabolism does not necessarily need it. If you get out of breath during exercise, it's a rough indication that you're burning mostly carbohydrates.
Therefore, during a moderate workout, more fats are burned directly than during intense workouts. This trains your fat metabolism and in the long run your body learns to metabolize more fats during training. Very well trained endurance athletes, for example, can still use significant amounts of fat as an energy source even at intensities significantly higher than 70% because they have a very well trained fat metabolism. Especially during long and intense workouts and competitions, this ability is essential because even the fullest glycogen stores will eventually be empty, but fat reserves are relatively large.
Which is better?
In making this distinction, it is very important to understand that during fat burning, proportionately more fats are burned. This means that the proportion of total calories consumed is a higher proportion of fats, not that more fat is consumed overall. This is mostly the case with fat loss, since higher training intensities also burn more calories and thus the fat depots can be tapped to a greater extent after training.
Does this mean that fat burning is worse? No, because, as already mentioned, the training of the fat metabolism serves in the medium and long term to be able to burn fats even during intensive training. Accordingly, the goal of this form of training is in some ways different:
While the goal of fat loss is directly related to the calories consumed and the type of substrates burned during the workout is secondary, fat burning does not aim at maximum energy expenditure, but at the most efficient energy expenditure possible. Furthermore, a well-trained fat metabolism is important not only for the loss of body fat, but also, as mentioned above, for athletic performance during long sessions.
Why not do both?
Accordingly, the question should not be "Which is better?" but rather, "Why not both?" - After all, it stands to reason that the highest possible caloric expenditure combined with the highest possible percentage of fat burned has synergistic effects. Therefore, you should also combine both forms of training to optimally lose body fat and increase performance.
For your fat metabolism training, use rather moderate intensities up to 70 percent of the maximum heart rate for longer sessions. If you train without a heart rate monitor, be careful not to get too out of breath. For the highest possible calorie consumption and optimal reduction of body fat, you can also train more intensively and for a shorter period of time, or incorporate intervals into long sessions.
But be careful: Beginners in particular tend to get into high heart rate zones quickly because they do not yet have a well-developed fat metabolism and basic endurance. After an interval, the heart rate continues to decrease very slowly, which is why it can make sense to separate the intensities into several units.
Those who do strength training regularly are probably also in the higher heart rate ranges at times during the training sets and are probably better trained there than in the lower ranges. For most strength athletes, therefore, basic endurance training or fat metabolism training is the better cardio supplement.
What supports fat burning
If you want to further support your fat burning in training, there are a few more things you can consider. First, caffeine can stimulate fat burning and therefore increase energy supply via fats during exercise, while also increasing heat production and therefore energy expenditure via effects on the central nervous system. Furthermore, caffeine can thereby also improve physical performance as well as mental focus and thus contribute to increased energy consumption. Thus, caffeine supports both fat loss and fat burning and can be useful as a supplement for your training.
In addition, several studies have already shown that the emptier the glycogen stores were, the better the provision of fats during training. Therefore, especially moderate fat-burning training in a fasting state can increase the utilization of fats and thus the proportion of fats in total calories. Fasting cardio training therefore further enhances fat burning training. But a high-fat diet can also increase the oxidation rate of fats.
But beware. Excessive intensities on an empty stomach can result in valuable proteins being used as energy sources instead of building material in place of the missing carbohydrates. Although glycogen stores are rarely completely depleted even after a period of no energy intake, you can still play it safe and take BCAAs or EAAs as muscle protection before training to prevent the dreaded muscle loss caused by cardio training.
During fat metabolism training you burn a high percentage of fats directly during the workout. In contrast, during fat loss during training, carbohydrates are increasingly broken down and the missing energy is mobilized from fat stores in case of a negative energy balance. While fat burning occurs primarily at low to moderate intensities, but can be trained, carbohydrates are primarily burned during higher efforts. Both for the reduction of body fat, as well as for the build-up of performance, it makes sense to combine both forms of training. Supplements such as caffeine and amino acids can support your training.