A blood flow stimulating device including a boot including a sole and an upper; a sock disposed within the boot; and a bladder disposed within or on the sock, wherein the bladder is configured to undergo repeated inflation and deflation so as to stimulate blood flow in a wearer of the blood flow stimulating device, wherein the sock further includes a toe region, a heel region and a raised portion between the toe region and the heel region that, in use, reduces the distance between the sock and a foot of a wearer of the blood flow stimulating device at the raised portion of the sock.