The invention concerns an implantable pulse generator (106) that is connected or can be connected to a stimulation lead (100) having a plurality of stimulation electrodes (102, 104) for delivery of stimulation pulses. The implantable pulse generator (106) comprises at least one stimulation unit (36, 38, 40, 42, 44, 46) that is configured to generate electric stimulation pulses for nerve stimulation. The implantable pulse generator (106) further comprises a control unit (50) that is configured to trigger delivery of generated electric stimulation pulses via selected electrodes of the plurality of stimulation electrodes (102, 104) wherein said electric stimulation pulses form a pulse train comprising:i) an initial selective-arrest phase for the large-diameter fibers in the vicinity of selected electrodesii) followed by a phase where a charge-balanced alternating current (AC) is applied between the same or other selected electrodesiii) and where such AC is briefly unbalanced to effectively deliver nerve stimulation therapy pulses, returning to charge-balanced operation in between therapy pulses.
