I said the racquet does most of the work TO PROPEL the ball, not "most of the work." The point is, at what point does the tool of the game negate the athletic activity? The JaiAlai cesta is another example. No way a human arm can throw a ball at over 120mph. So does the use of the cesta negate Jai alai as a spport? As to comparing Wii with constipation, unless there is some one trying to insert a cork as you try to go, it is false equivalency.
I know. The work to propel the ball is still ALL done by the player. In fact it requires even more work by the player to use the racquet than if the player were to swing his/her arm without a racquet. Without getting too much into physics and the definition of work, the reason the ball goes faster off a racket than a bare hand is because the extra length provides additional velocity. Force (work) = 1/2 x mass x velocity^2. It is that additional squared velocity created simply by extending the lever (arm + the racket) past the fulcrum (the shoulder) that creates much more force when contacting the ball. Add the slight additional mass of the racquet to the formula and you get a ball that comes off a racquet much faster than a bare hand. Plus the racquet absorbs less energy than a hand would.
If you were to hit a tennis ball with a solid iron rod the ball would come off the rod with even more velocity. That is not because the rod is doing more work or has more energy behind it. It is because the rod has more mass and is more solid (absorbing less of the energy from the ball). This requires even more work from the player swinging the rod.
All of that velocity is created only by the player, and the energy of the ball hit back by the other player. Zero energy to propel the ball comes from the racquet alone.
Whereas with auto-racing most of the work and energy comes from the car itself. Much more joules are used from the car burning fuel than the driver controlling the car.
Sorry for getting geeky, but that is how I think. I do not know of any other way to explain the difference between the car propelling itself and the racquet propelling the ball when it comes to the amount of work being done.
And then there is the definition of "game". What is your definition of a "Game". Competitive long-distance cycling where you have offensive and defensive moves according to rules qualify as a game under the standard definition of game, and it is definitely an athletic activity.
---Game: [n] A form of play or sport, esp. a competitive one played according to rules and decided by skill, strength, or luck.
Sometimes official definitions are somewhat paradoxical. The definition of a game includes the word sport and the definition of a sport includes the word game.
I know by the official definition many things that I do not consider a sport, are officially called sports.