  We analyse the ionized gas kinematics in the star formation regions of the
supergiant shell (SGS) of the IC 2574 galaxy using observations with the
Fabry-Perot interferometer at the 6-m telescope of SAO RAS; the data of the
THINGS survey are used to analyze the neutral gas kinematics in the area. We
perform the 'derotation' of the H-alpha and HI data cubes and show its
efficiency in kinematics analysis. We confirm the SGS expansion velocity 25
km/s obtained by Walter & Brinks (1999) and conclude that the SGS is located at
the far side of the galactic disc plane. We determine the expansion velocities,
kinematic ages, and the required mechanical energy input rates for four star
formation complexes in the walls of the SGS; for the remaining ones we give the
limiting values of the above parameters. A comparison with the age and energy
input of the complexes' stellar population shows that sufficient energy is fed
to all HII regions except one. We discuss in detail the possible nature of this
region and that of another one, which was believed to be an SNR according to
radio observations. We measured the expansion velocity of the latter and
confirm its identification as an old SNR. Our observations allowed us to
identify a faint diffuse H-alpha emission inside the SGS which was never
observed before.

Astrophysics of Galaxies