The amount of body fluid present in the user's head, an estimation unit that estimates one or both of the amount of change in the amount of body fluid, and the amount of body fluid estimated by the estimation unit, or any one or both of the amounts of change A G tolerance improving device comprising a pressurizing unit for applying pressure to a user.ユーザーの頭部に存在する体液量、前記体液量の変化量のいずれかまたは両方を推定する推定部と、前記推定部が推定した前記体液量、前記変化量のいずれかまたは両方に基づいて前記ユーザーに圧力をかける加圧部と、を備えるＧ耐性向上装置。
