We consider a compact locally maximal invariant set K of a
C²-diffeomorphism f:M→M on a smooth Riemannian manifold M. We
study the topological pressure (with respect to f|K) for a wide class of
Hölder continuous potentials. Under a mild nonuniform hyperbolicity
assumption we show that the pressure of an appropriate potential is
entirely determined by its values on periodic orbits which have
sufficiently strong hyperbolic behavior.
We also consider the case of the potential that relates to the volume
growth rate and study its saddle point pressure.