The diver swings his arms upward and begins to release his pressure on the board. The board pushes the diver up and into the air with a huge force. This force now can be used by the diver not only to go up, but to rotate and therefore perform various dives. The Dives and Application To do a front dive a diver pushes his hips upward just slightly as he leaves the board. After he had begun to go up into the air, he throws his arms downward just enough to make is upper torso rotate around his hips.
At the peak of the dive, the diver tightens his stomach muscles and pulls his legs up towards the sky, leaving his body in a perfect upside-down position to enter the water head-first. In order to perform a front dive with a somersault, it requires a full flip of the body and therefore it takes a quicker rotation to cover such an angular distance. The diver takes off from the diving board with the same hip motion and arm swing as for a forward dive, but throws the arms further and makes a smaller “ball” in the air.
As is seen in the laws of rotational motion, the diver’s moment of inertia becomes smaller, but since momentum must be conserved in the system, the angular speed increases to compensate. It is important to note here that the reverse can be applied in order to stop the diver’s rotation to keep him from doing a belly-flop on the water. To stop his rotation, the diver increases his moment of inertia by straightening his body, conserving momentum again. When a diver goes to jump off of the board backwards, he begins by swinging his arms down with a deep knee bend.
Just as in the hurdle, this presses the board down. When the diver lets the diving board recoil, he does two things at the same time: He swings his arms back up and jumps up. The board assists the diver just as in the hurdle and he has the ability to put this new energy to use. To do a back dive, the diver pushes his hips up as he leaves the board. Once airborne, he leans back and pulls his hips upward even more, generating just enough rotation to go into the water headfirst.
To do a back dive with a somersault, the diver pulls his hips upward while leaving the board. As the rotation begins, he swings his arms around and grabs his knees to make himself smaller. Again, just as is accomplished with the front dive with a somersault, the moment of inertia is made smaller and the angular speed increases to make enough spin that is needed to complete the somersault. Reverse Dives You would think that there was a similar technique between performing a back dive and a reverse dive, which is true.
A forward hurdle is applied before the dive, but when the diver leaves the board, he pushes his hips upward and leans back enough to create a backwards rotation and enter the water head first. Again, just like the back dive with a somersault, the same laws of physics allow for a diver to perform a reverse dive with one-and-a-half somersaults and enter the water headfirst. A smaller moment of inertia leads to a greater angular speed. Inward Dives Although the take-off for an inward dive is like that of a back dive, the techniques used in the air are exactly like those that are used to perform a front dive. Twisting Dives
The front dive with one somersault and one twist can appear to be tricky, but it involves the same conservation of momentum as the other dives, only along two axis of rotation. When the diver takes off from the board, he begins his flipping rotation by throwing his upper body down towards his legs. Next, he unfolds while rapidly wrapping his arms about his body. This begins the twisting motion. From here, all the diver has to do is figure out what his orientation in the air is in order to know when to straighten his body to counter the flip and when to unwrap his arms to counter the twist before entering the water.