The invention concerns a method for determining a progressive ophthalmic lens for a given user for whom a near vision power addition has been prescribed, including the following steps: measuring the lowering of the user's eyes and a vertical horopter of the wearer on a near-vision target point; measuring the user's near-vision head elevation and/or eye elevation; determining a coefficient of the user's near-vision vertical head movement (Ptvvp); determining a user-specific progression length (LP) defined by the relationship LP= H (1- Ptvyp), the progression length being defined as the eye-lowering angle between the mounting cross and the meridian point for which the power achieves the power addition; determining the lens by optimizing in optical computation in use conditions, using as the target a power variation along the meridian with a progression length equal to said user-specific progression length.