Density profile of a 79 M_⊙ solar metallicity core-hydrogen burning model showing the inflated envelope. The model had an initial mass of 100 M_⊙. The radial co-ordinate has been scaled with the core radius r_core. The blue line (right Y-axis) shows the run of the Eddington factor Γ (Eq. (4)) in the interior of the model. The Eddington factor almost reaches unity in the inflated region.