Objective: To evaluate the addition of blood flow restriction to passive mobilization in patients in the intensive care unit. Design: The study was a within-patient randomized trial. Setting: Two intensive care units in Belém, from September to October 2017. Subjects: In total, 34 coma patients admitted to the intensive care unit sector, and 20 patients fulfilled the study requirements. Interventions: All participants received the passive mobilization protocol for lower limbs, and blood flow restriction was added only for one side in a concurrent fashion. Intervention lasted the entire patient's hospitalization time. Main outcome measurement: Thigh muscle thickness and circumference. Results: In total, 34 subjects were enrolled in the study: 11 were excluded for exclusion criteria, 3 for death, and 20 completed the intervention (17 men and 3 women; mean age: 66 ± 4.3 years). Despite both groups presented atrophy, the atrophy rate was lower in blood flow restriction limb in relation to the