A foot support system (1000, 4000, 5000, 6000), comprising: a fluid transfer control system including a first port, a second port, a third port, and a fourth port, wherein the fourth port is in fluid communication with an external environment; a first pump connected to the first port; a reservoir connected to the second port; and a foot support bladder (700, 700A) connected to the third port, wherein the fluid transfer control system selectively places the foot support system (1000, 4000, 5000, 6000) in any one of six operational states as follows: (a) a first operational state in which fluid moves from the first pump, into the fluid transfer control system, and through the fourth port to the external environment; (b) a second operational state in which fluid moves from the first pump, into the fluid transfer control system, and through the second port to the reservoir; (c) a third operational state in which fluid moves from the reservoir, through the fluid transfer control system, and through the third port to the foot support bladder (700, 700A); (d) a fourth operational state in which fluid moves from the foot support bladder (700, 700A), through the fluid transfer control system, and through the fourth port to the external environment; (e) a fifth operational state in which fluid moves from the first pump, through the fluid transfer control system, and through the third port to foot support bladder (700, 700A); and (f) a sixth operational state in which fluid moves from the reservoir, through the fluid transfer control system, and through the fourth port to the external environment. a fluid transfer control system including a first port, a second port, a third port, and a fourth port, wherein the fourth port is in fluid communication with an external environment; a first pump connected to the first port; a reservoir connected to the second port; and a foot support bladder (700, 700A) connected to the third port, wherein the fluid transfer control system selectively places the foot support system (1000, 4000, 5000, 6000) in any one of six operational states as follows: (a) a first operational state in which fluid moves from the first pump, into the fluid transfer control system, and through the fourth port to the external environment; (b) a second operational state in which fluid moves from the first pump, into the fluid transfer control system, and through the second port to the reservoir; (c) a third operational state in which fluid moves from the reservoir, through the fluid transfer control system, and through the third port to the foot support bladder (700, 700A); (d) a fourth operational state in which fluid moves from the foot support bladder (700, 700A), through the fluid transfer control system, and through the fourth port to the external environment; (e) a fifth operational state in which fluid moves from the first pump, through the fluid transfer control system, and through the third port to foot support bladder (700, 700A); and (f) a sixth operational state in which fluid moves from the reservoir, through the fluid transfer control system, and through the fourth port to the external environment. (a) a first operational state in which fluid moves from the first pump, into the fluid transfer control system, and through the fourth port to the external environment; (b) a second operational state in which fluid moves from the first pump, into the fluid transfer control system, and through the second port to the reservoir; (c) a third operational state in which fluid moves from the reservoir, through the fluid transfer control system, and through the third port to the foot support bladder (700, 700A); (d) a fourth operational state in which fluid moves from the foot support bladder (700, 700A), through the fluid transfer control system, and through the fourth port to the external environment; (e) a fifth operational state in which fluid moves from the first pump, through the fluid transfer control system, and through the third port to foot support bladder (700, 700A); and (f) a sixth operational state in which fluid moves from the reservoir, through the fluid transfer control system, and through the fourth port to the external environment.