Study cunducted with the Veneuelan National Team of Wrestling Freestyle and Greco-Roman, both male and female, that participated in a medium-level altitude training stage (2,850 m.a.s.l), during three weeks (22 days), in Quito, Ecuador, as part of the training microcycle before the VII South American Games, Buenos Aires 2006. The purpose of this study was to determine the influence of the adaptation, functional, hormonal and biochemical changes causes by medium-level altitude training. Heart frequency, orthostatic index, (lactato, urea, CK, cortisol and testosterone in blood) were the variables used. Lactato and heart frequency appeared during combats in the training stage, while urea, cpK, cortisol and testosterone in blood the same day in athletes with an empty stomach, before the combats in the training stage. We obtained the samxe results in the three microcycles during the medium-level altititude training. We also observed a slight increase in the lactato levels in blood and in the heart frequency untill reaching a significant stabilization, as a response to the combats in the training stage in the three microcycles. Lactacidemia decresed as the adaptation process advanced. Medium-level altitude training affected positively heart frequency, according to lactato increase. Urea and CK tests proved to be useful in the cases athletes adapted to the training loads or where the volume of training loads was decreased. Also, hormonal tests with cortisol and testosterone proved to be useful regarding training loads.