Disclosed and claimed are cap (120), skullcap (200), hat (270), and hat insert (350) devices comprising a weight-increasing layer, such as an elastomeric weight layer (114, 214, 350, 414, 454, 514). The elastomeric weight layer (114, 214, 350, 414, 454, 514) is comprised of an elastomer and weighted bodies. In some embodiments the weight-increasing layer is shaped to conform to the crown of the head of a person wearing headwear of the present invention. In other embodiments a weighted component fits within a hat. Other forms of the weight-increasing layer include a double-walled bladder structure (700), shaped to conform to a person's head, into which weighted material is added. Exercise with such devices serves to increase the bone strengthening weight stress experienced by the wearer's spinal column and to encourage the wearer to maintain an improved, healthier posture.