The study works with the perspective of investigating the influence of postdoctoral studies on scientific production and, more specifically, compares the collective academic performance of researchers who have opted to realize a postdoctoral research with those who have not done so along their careers. The training is an extra item in the academic career, acting as a knowledge-updating and upgrading process through socialization and contact with mainstream science. This paper constitutes an exploratory study circumscribed by the broad fields of biological, engineering, exact and geosciences, and health. With a population of 86 doctors (PhDs) who completed postdoctoral research before June 2005 and a sample of 198 professors with and without postdoctoral work, and working in graduate programs at USP in Brazil, the results point out differences and a positive influence of the postdoctoral research, especially when a longer time span has elapsed since the conclusion of the doctor’s degree. Among professors with postdoctoral research realized there is a trend for increased production, but it is not a strong and incisive one; even when considering a longer period of time after obtaining the doctoral degree, various cases of professors with similar performances were observed, independently of the realization of postdoctoral studies.