Currently, the number of patients with chronic kidney disease is increasing. The main problem in chronic kidney disease patients is the reduction of blood flow to the kidneys, causes the insufficient blood supply to the kidneys. As a result, the accumulation of waste in the body due to the renal function excreted less waste from the body. It leads to a gradual decline in kidney function. In the elderly, it is found that blood flow to the kidneys decreased. The purpose of this study was to compare the effects of renal blood flow and heart rate variability before bed rest, after bed rest, and after the trial in the elderly. The 41 healthy elderly volunteers were divided into three groups: foot massage group (14 persons), foot exercise group (14 persons), and control group (13 persons). All of them were received bed rest for 15 minutes, then got a foot massage or foot exercise or bed rest for 15 minutes. Volunteers were measured for renal blood flow and heart rate variability for 3 times and 24-hours urine analysis was measured before and after the trial. The results found that renal blood flow and 24-hours urine analysis were not significantly different from the pre-treatment and no difference between groups. In massage group found that the standard deviation of the normal-to-normal intervals (SDNN), the square root of the mean squared differences of successive normal R-R intervals (RMSSD), and low frequency (LF) were significantly increased (p<.05). In foot exercise group found that SDNN and RMSSD were significantly increased (p<.05). And the control group found that only RMSSD was significantly increased (p<.05). However, there was no difference between groups comparison. Conclusion, the foot massage, the foot exercises, and bed rest could increase the heart rate variability by increasing the activity of the parasympathetic nervous system. But it does not affect the renal blood flow.