[en] In this study, we have demonstrated the enhancement of laser-to-core energy coupling using magnetized fast isochoric laser heating on the GEKKO-LFEX laser facility. We achieved a maximum coupling of 8% by applying an external magnetic field, and the coupling gradually degraded with increasing energy of the heating laser, maintaining the pulse duration and the spot diameter constant. The obtained energy couplings are consistent with those obtained using simple calculation models. The models predict that an energy coupling of 20% - 35% can be achieved by an ignition-scale core exhibiting a moderate guiding field and heating laser intensity. (author)