A nice overview of seating position by Sport Singapore.
Also, in this video notice the hand position on the steering wheel. Specifically, the position of the thumbs.
Sometimes, when a driver holds the steering wheel at a low position they tend to wrap their thumbs over and around the tops of the lower steering struts. Or, put a death grip on the steering wheel resulting in the thumbs clinch/hooking around the wheel. The overly wrapped thumbs style can lead to injury. In the event of an accident, the steering wheel can be violently jerked damaging the thumb, hand and wrist.
The ideal position is shown in the image at the left. The thumbs are slightly vertical and not wrapped around in a hook style. In this position, if the wheel is violently spun around the struts will more likely lift the thumb.