From Chabad.org:
The swimming instructor had just concluded his ten-minute introductory lecture on the joys and perils of swimming. "Any questions?" he asked.
Ten-year-old Bobby raised his hand. "Can I play with my Gameboy while we're swimming?"
"No, Bobby," replied the instructor. "We shouldn't have any electronic devices with us in the water..."
"How about Scrabble then? Can I play Scrabble while I'm swimming -- that's not electronic."
"No, Bobby, I don't think that would be possible."
"Can I wear my new cowboy boots?"
"I really wouldn't recommend wearing cowboy boots while swimming, Bobby."
And so it went. Bobby was disappointed to learn that he couldn't ride his bicycle, play the piano, paint the garage or eat a grilled cheese sandwich while swimming. He finally left in disgust -- who needs swimming anyway, if all it is a bunch of you're-not-alloweds!
Bobby, of course, was being ridiculous. Swimming is not a bunch of don'ts. Swimming is a positive activity. Obviously, if you're going to be swimming, you're going to stop doing all the things that interfere with that activity.
Shabbos is the same. If you really want to be Shomer a Shabbos the way Hashem wants you to, perhaps you need to refrain from many of the weekday activities in order to do this.
