-6 degrees head down bedrest (HDBR) 10d was used to simulate weightlessness. 12 volunteers were randomed into control group and cuffs group, with 6 in each group. Inflated cuffs on the upper part of thighs and arms were performed 12 h/d in cuffs group during bedrest. No countermeasures were applied in the control group. During head up tilt (HUT) +75 degrees 20 min orthostatic tolerance test after HDBR, 5 in control group became presyncopal, while only one in cuffs group. The study indicates that the use of inflated cuffs provides a protective effect against the cardiovascular deconditioning after bedrest.