Electronic stimulation of muscle activity to strengthen the muscle hasn't been proven that contraction of muscles when caused by outside forces makes the muscle stronger. In addition, even if facial muscles were made to be stronger, it doesn't mean they would pull up a saggin face as the muscles are used from different angles to move the mouth, jaw, eyelids, etc. Devices that are designed to tighten the SMAS connective tissue layer and to induce new collagen production may help lift the face, such as Ultherapy which is FDA cleared to lift the forehead, and Botox is an excellent adjunct to Ultheapy. Whether or not Botox and electronic muscle stimulation are antagonistic or complementary is not known.