It is reported that persons driving auto gear cars for long distances need to take certain precautions to protect their health. It is advised to take break after 1-2 hours of drive to do some exercise.
It is reported that person driving automatic car will not use left leg and there is a valve in leg to control blood flow to the heart. Other information is available in the news paper report.
The news paper report in this aspect is given below.
https://timesofindia.indiatimes.com/life-style/health-fitness/health-news/why-long-drives-in-automatic-cars-may-be-dangerous-for-you/articleshow/72182040.cms
I got certain doubts about this, but may be it depends on person to person. The person referred in the news report is driver. However, the other occupants in the vehicle will be sitting throughout the journey whereas the driver will be moving atleast one leg.
Another question that arises is what about persons with amputated legs.