[Theoretical analysis of the efficacy of G suits during exposure to continuously increasing gravitational overloads]

A mathematical model of human circulation was employed to examine circulation responses to +GZ acceleration the value of which increased linearly at the rate 0.1 G/sec, using subjects having an anti-G suit on and sitting in a relaxed posture. It has been calculated that the anti-G suit can compensate as much as 83% of the increment of hydrostatic pressure in leg vessels and as much as 57% in abdominal vessels. The suit effect on resistance and capacity vessel properties makes an approximately equal contribution to an increase of the acceleration tolerance threshold. However the occlusion effect of the anti-G suit causes a significant increase of afterload.