This way to equalize is popular among beginners who first come to a
freediving courses due to its simplicity: simply close your mouth, pinch your nose, and try to exhale, which creates pressure that pushes air through the Eustachian tubes into the middle ear, equalizing the pressure on the eardrums.
However, for freediving, where the dive is performed without scuba and in a vertical position, valsalva maneuver not working so easy. The fact is that as the depth increases, the volume of the lungs decreases, and the use of abdominal muscles to push air out of the lungs becomes difficult. The Valsalva maneuver can be risky at great depths, increasing the likelihood of lung and ear injuries due to the need to exert more effort.
Furthermore, the Valsalva maneuver is associated with tension and excessive oxygen consumption, which contradicts the main goal of freediving - maintaining relaxation and conserving energy. In this regard, although beginner freedivers may start with Valsalva, they should soon learn the Frenzel technique, which involves smaller and non-respiratory muscle groups, providing a softer and more controllable pressure equalization, allowing for deeper dives.