Nutritional knowledge can be characterized as a set of information acquired about food and nutrition through the skills of the cognitive process, or it is simply what is understood in relation to the general aspects of food. The aim of this research is to describe what scientific publications say about nutritional and supplemental knowledge among physical activity practitioners. This is a bibliographic review in which 16 scientific articles researched in the database SCIELO and Google Scholar in Portuguese were used between the years 2011 and 2019. The research participants are concerned with matters related to nutrition, however, there is little guidance, requiring a professional nutritionist together with the physical educator. Physical activity practitioners seek information from gym instructors, physical education teachers and also follow self-indication, which directly reflects in their conduct related to nutrition. It is concluded that, although most physical activity practitioners are interested in aspects of healthy eating, they have a moderate nutritional knowledge. There are erroneous practices and little knowledge in relation to dietary supplements, as well as the search for information and nutritional guidance with people not qualified for this purpose.

Beetroot is highly rich in important chemicals and stands out for its high concentration of B vitamins and various nutrients. In its chemical substances, beet has a high concentration of inorganic nitrate (NO₃), a substance used as an ergogenic supplement when related to therapeutic treatments, being a multifunctional physiological signal, essential for health and vascular function. Our body, when subjected to a stimulus, tends to leave its homeostatic state, and the chemical component present in beets, nitrate, will be responsible for activating an effective vasodilation, due to the conversion of nitrate into nitric oxide. The objective of the present study will be to analyze in scientific articles, which relate the effect of supplementation with beetroot juice as a pre-workout, in improving the performance of physical exercise practitioners, and the effects of using beetroot juice as a supplementation strategy for cardiorespiratory resistance, as well as to understand other possible benefits allied to its use with regard to the vasodilator effect, providing greater oxygen supply to the muscle, muscle fatigue.