The reason why blood vessels look more obvious in people with less sebum or thin figure is that blood vessels are naturally exposed because there is less subcutaneous fat, so those fat people with subcutaneous fat are basically not exposed. Thin people have less fat and muscle, and their metabolic ability is fast, which leads to obvious blood vessels. You can see turquoise and dark red blood vessels through the skin.
People who exercise for a long time are generally athletes, fitness enthusiasts and amateur sports enthusiasts, and their blood vessels will be more obvious than ordinary people. Mainly because they usually exercise a lot, and their bodies are basically lean meat and less fat, especially fitness enthusiasts. They will practice excess fat for the beauty of muscles, and blood vessels are often clearly identifiable.
It is generally the working people who often engage in heavy physical labor, including migrant workers on construction sites, farmers in the fields, stevedores at stations and docks, etc. The difference between them and ordinary workers is that they often have to make great efforts and do heavy physical labor. When exerting force, the blood circulation of human body will be accelerated and blood vessels will expand to a certain extent. Over time, blood vessels will thicken in order to adapt to this situation, which is more obvious from the body surface. Therefore, people who often do heavy work, in fact, have thicker blood vessels than ordinary people, faster and larger blood flow, and are naturally more powerful than ordinary people.