As I mentioned above the side to side balancing that you do on your kayak is basically the same as the motion on your kayak.
The basic premise in standing in your kayak (or even siting and moving around in your kayak for that matter) is that where ever your head goes your body will follow. Most people tip or fall off of their kayaks because they lean too much one way or another and their head is sticking way over one side of the kayak.
The Indo Board allows you to practice balancing using your hips to move with the board instead of moving your upper body.
This product was created for surfers and has transitioned into just about all board sports but I personally think that it is a great way to train for standing in your kayak as well.
For more information regarding this product please vistit: http://indoboard.com