Meaning in images

You're familiar, of course, with these two famous images:

Bart Simpson and his sister Lisa.

Now, close your eyes and form the following image in your mind. Bart has unzipped his blue shorts and pulled out his pecker. His adorable wide-eyed sister has leaned down in front of him and started to give her brother a tender Olympian blowey... as they say in the sporting classics. Specialists (elsewhere on the Internet) have suggested that this incongruous composite image might look something like this:

You've recognized, of course, the logo of the forthcoming Olympics in London.

One might wonder what the athletes in the Olympic Village are going to be doing in their spare time, when they're not actually competing. Training, of course...