Barry Allen always lost in races as a child, as he was always slow. However, he was good in science at school.
Barry went to college and got a degree in chemistry.
Barry Allen was a police scientist. One day in his lab a lightning bolt came down shattering chemical bottles on him. He woke up realizing that he was late for a date with his wife. He started running. He passed several cars. He realized that he had super speed. He used this to become The Flash! He is a founding member of the Justice League and is still in the league. A few years later he met Quicksilver and they had a race. It was a tie.