4D massage represents an advanced technology of massage heads, building upon the principle of 3D massage. While 3D massage allows the heads to move not only up, down, and sideways, but also forward and backward to regulate pressure intensity, 4D technology adds another element. This fourth dimension is the variable speed and rhythm of the massage heads' movement. During the massage program, the heads therefore not only change pressure but also accelerate, decelerate, or take short pauses. This dynamic movement better mimics the technique and touch of a professional masseur's human hands, making the massage less monotonous and more natural.