High current density in high field Tokamaks, like FT, allows the full exploitation of ohmic heating and in addition the attainment of very high density. Energy confinement results of FT, especially at high density regimes, are reviewed and discussed. Moreover power balance with additional heating, RF power at lower hybrid frequency, is presented, showing that, at least for the present level of power and density range investigated, no deterioration of energy confinement time is found. The scientific objectives of FTU, under construction at Frascati, are also presented in view of the experience gained by operation of FT.