BIOMECHANICAL PERSPECTIVE OF SWIM DIVING
Potential Energy
Potential energy is “energy an object has due to its position” (McGinnis, 2005). Strain energy is a type of potential energy that is stored when an object is stretched out of its original shape and can then recoil to generate a substantial amount of force and momentum (Carr, 1997)(Burkett, 2010). This works much like a rubber band in that the further you stretch the rubber band, the more recoil the object has and the more strain energy can be created (McGinnis, 2005). Stiffness of the muscles can also effect strain energy and recoil (McGinnis, 2005).
Strain energy is a key biomechanical principle in the two swimming starts. Both starts use strain energy when the swimmer shifts their body weight towards the rear of the block. This stretches the upper leg, upper arm and shoulder muscles, which stores elastic potential energy, which is then released as the swimmer executes the dive and leaves the block. The track start stores more strain energy as the swimmer can move further back on the block due to a wider base of support and a further stretch in the leg muscles. The grab start still allows strain energy to be used, however it is far less due to the fact that the base of support is much smaller and the leg muscles are not stretched to the same extent as the track start.
Potential energy is “energy an object has due to its position” (McGinnis, 2005). Strain energy is a type of potential energy that is stored when an object is stretched out of its original shape and can then recoil to generate a substantial amount of force and momentum (Carr, 1997)(Burkett, 2010). This works much like a rubber band in that the further you stretch the rubber band, the more recoil the object has and the more strain energy can be created (McGinnis, 2005). Stiffness of the muscles can also effect strain energy and recoil (McGinnis, 2005).
Strain energy is a key biomechanical principle in the two swimming starts. Both starts use strain energy when the swimmer shifts their body weight towards the rear of the block. This stretches the upper leg, upper arm and shoulder muscles, which stores elastic potential energy, which is then released as the swimmer executes the dive and leaves the block. The track start stores more strain energy as the swimmer can move further back on the block due to a wider base of support and a further stretch in the leg muscles. The grab start still allows strain energy to be used, however it is far less due to the fact that the base of support is much smaller and the leg muscles are not stretched to the same extent as the track start.
This video shows the different amounts of strain energies between the grab start and track start.