A method was worked out for the detection of the additional energy release behind the detonation wave on the basis of the measurement of the shock wave velocity in a plexiglass block. Explosives tested were NH₄NO₃/TNT 80/20,NH₄NO₃/TNT/Al 80/10/10,NH₄NO₃/TNT/LiF 80/10/10 and NH₄NO₃/Al 90/10. It was established that a decrease of the shock wave velocity with increasing distance from the explosive charge. It can be slowed down by using aluminized explosives and the higher dispersity of Al,the slower decay of the shock wave velocity is. These effects are caused by an increase in pressure of explosion gases acting on the plexiglass boundary as a result of releasing the additional chemical energy from aluminium oxidation.