A phenomenological nonlinear model, describing a reconstruction of the
living organism after strong loading have been proposed. This model i
s describing a restitution dynamics of the organism functional state t
o the initial state, including a supercompensation stage. In a simples
t (one-component) case this model is overdamping Duffing oscillator. I
t is shown that the mutation phenomena may be described as the phase t
ransition within the framework of Landau-Khalatnikov approach. A gener
alized many-component nonlinear reconstruction model is proposed.