A garment for men and women comprising two sleeves (1.2, 3.3) having a tight fit when a user is wearing the garment, a back piece (1.1, 2.3), arranged to be attached to both sleeves (1.2, 3.3) at respective back seems (1.4, 4.1, 4.4) and a front piece (2.1, 3.4). The garment comprises an inner back piece (2.2, 3.5, 4.2) being attached to both sleeves (1.2, 3.3) at the respective back seams (1.4, 4.1, 4.4). The inner back piece (2.2, 3.5, 4.2) has a length between the back seams (1.4, 4.1, 4.4) of at least 1 cm shorter than a length of the back piece (1.1, 2.3), a width between 8 cm to 20 cm and an elasticity so that the fabric can expand by a maximum of 20% of its original length so that the position of the shoulder is guided to stimulate the user to hold the shoulder blades together.
