The aim of this study was to determine the effects of localized inactivity or immobilization on calf blood flow by comparing with the leg fixing plaster cast and free. Fourteen male patients (Experimental Group; EG) with accidental leg breaks and wearing plastic leg casts from two to four weeks, and twenty healthy males (Control Group; CG) were employed. The blood flow in both calves was determined simultaneously to the venous occlusive plethysmography at rest and after exercise which were voluntary dorsi-planter flection (VDPF) at one flex per second for three minutes and treadmill walking (TW, Flat: 50 to 80 m/min) for three minutes. In the experimental group, the subjects were performed VDPF exercise on 14 days after the cast was shelled, and TW exercise on 39 days after the cast was removed, respectively. The calf blood flow of active and inactive legs at rest was not different, while lower blood flow of calf of inactive after VDPF exercise was in the EG. After treadmill walking, calf blood flow of inactive leg was significantly higher than active. In control group, however, calf blood flow did not differ from right to left leg at rest and after exercise. These results suggest that inactive or disuses causes atrophy of muscle and ligament and secondary to the neurological disorder and contracting length of muscle was diminished at VDPF exercise. Furthermore, the higher reactive hyperaemia of fixed leg calf after walking is expected by a low muscle activity level i.e., inactivity or disuse, and may lead to a reduced oxidative enzyme activity in muscle tissues.