The first time I drove a prius. My left leg went into cramps. I could bearly get out of the car. After a few steps the pain went away. I added about 2 inch cushion to my seat. Now every once in awhile my leg will cramp at the knee. Now I am able to bring my leg back and cross it along side the seat and the pain goes away. I am 5 ft 6 in.
<div class='quotetop'>QUOTE(Spike Jones @ Nov 4 2007, 07:30 AM) [snapback]534602[/snapback]</div> Unfortunately the Prius does not have seat height adjustments. But what you describe is a medical issue, not a vehicle isue. My wife (who's also 5' 6", drives a Prius, and is a doctor) says you may have a nutrient deficiency of some kind.
I am also 5'6" and have driven up to 10 hours and not cramped. You might want to have that looked at?