Before the training
Whether endurance or weight training. No matter. Actually, you should always eat something small before you take any decent physical exercise. Your body needs this "support".
Whether banana, protein bars or other power snacks. In a healthy mass your body simply needs it! After all, what should it use if you haven't eaten for more than ten hours? Smart as the body is, it takes energy where it shouldn't. The consequences after training are ravenous appetite attacks that can destroy your whole training.
While the training
Almost more important than the pre-workout care is the one during the workout. Here we are talking about liquid food.
High quality drinks without a lot of sugar. But drinks that your body during training z. For example, supply with essential trace elements, amino acids or vitamins. Protein drinks or bars are also great if you're feeling hungry during exercise. It is important that you increase the number of carbohydrates by about ten times during training compared to before training.
After the training
It is often said: "it is best to go into the shower with the protein shake immediately after training to achieve the best effect". That is absolute nonsense. From the moment the first training stimulus is given, the body is ready to process all the information from your shake and use it in a targeted way until about three hours later.
So: take "good" carbohydrates after training and increase the amount of protein in order to supply your muscles in a targeted way and to start your regeneration correctly. Do not drink any sweet drinks and be satisfied with your performance - because tomorrow is definitely coming!