  We present a model for the compression and heating of the ICM by powerful
radio galaxies and quasars. Based on a self-similar model of the dynamical
evolution of FRII-type objects we numerically integrate the hydrodynamic
equations governing the flow of the shocked ICM in between the bow shock and
the radio lobes of these sources. The resulting gas properties are presented
and discussed. The X-ray emission of the shocked gas is calculated and is found
to be in agreement with observations. The enhancement of the X-ray emission of
cluster gas due to the presence of powerful radio galaxies may play an
important role in the direct detection of cluster gas at high redshifts.
