  We consider a classical spinning particle in the frame of the relativistic
physics by means of a covariant Hamiltonian and of a generalization of Poisson
brackets which take into account the gauge fields. We obtain different
equations of motion and evolution in this context and we compare our results
with those of Bargmann-Michel-Telegdi. An extension to the case of a curved
space and a link towards quantum theory are given at the end of the paper.
