With you sitting in it, the kayak should float flat on the water without appearing bow or stern heavy. Some manufacturers offer replacement sets of thigh braces, placed closer to the seat, to fit shorter people. This is a better solution because it won't alter your weight distribution inside the boat. Another feature to consider is the degree of hook molded into the brace. Expert paddlers and rodeo contenders who seldom exit their boats always want a tighter fit than what might be comfortable for beginners.
Some manufacturers offer several versions of both their thigh braces with varying amounts of hook.
This is a valuable option. If no thigh braces are installed, the wedge-shaped foam knee pads sold to canoeists can be glued underneath the deck with contact cement. This is an elegant solution for touring kayakers. Wedge-shaped pads can also be glued underneath existing thigh braces to increase the amount of hook. The widest part of the wedge is glued on the side nearest the cockpit opening-the thicker the wedge, the tighter the outfitting.