Abstract. We study the behavior of Ma"n'e's action potential k associat*
*ed to a
convex superlinear Lagrangian, for k bigger than the critical value c(L)*
* . We obtain
growth estimates of the action potential as function of k. We prove that*
* the action
potential can be written as k(x, y) = DF(x, y) + f(y) - f(x) where f is*
* a smooth