I work out 4 times a week. 20 minutes running 40 minutes weight. Usually from 7pm to 8pm. I just want to eat healthy food, not supplements. I have heard that chocolate an coconut are good and healthy in a diet of someone practicing sport. Is it true? If so, in what way should I eat them and when?
When people talk about chocolate as a health food they are usually talking about dark chocolate, and in limited amounts. The current trend in coconut is around coconut water and coconut oil.
With respect to dark chocolate, the health benefits in one study for example indicated that "Dark, but not white, chocolate decreases blood pressure and improves insulin sensitivity in healthy persons."
For coconut oil and water it is largely around changing to a more (good) fat heavy diet and to add lauric acid to the diet which is tied to various health benefits. One is the increase of HDL (good cholesterol). See abstract from another study from the same journal. Coconut water is generally sometimes seen as a replacement for sports drinks, or for having high potassium content. See this news piece for a brief summary.
Both are generally associated with fat heavy diets, and attempts to keep a more even keeled insulin response in the body. This is all in terms of high quality, limited amounts of the foods, and not just mountains of desserts. For the dark chocolate it is still a dessert, just a better option.
Chocolate and coconut do not help or hinder in muscle definition. While they are both nutritious and healthy to be eaten in moderation, they will not assist you in your stated goal.
For muscle definition, protein food (and supplements) is your best bet. As long as you exercise the muscles constantly and eat nutritious meals (protein, fibers, fruits, and complex carbohydrates), your muscles should be defined.
Too much of chocolate and coconut might be detrimental though because they are still fatty food. So again, eat them in moderation.