The action of the weight of the body parts of a swimmer and assembly in equipment can be replaced by a resultant force of gravity, which is attached to a point called the center of gravity CG. This force is directed vertically downward. Similarly, the action of buoyancy forces can be replaced by a resultant force of buoyancy, the upward and attached to a point called the center of buoyancy of the CPU.
From the relative position of these two points will depend on stability of a swimmer under water. If the goods or machinery, are too high (above the CG CPU), an athlete can always be tilted upside down. If too low, the location of goods and apparatus (CT below the CPU) the athlete must exert to bend down. In either case, the swimmer will have to expend extra effort to give body to its normal position.
To preserve the stability of the water must comply with two conditions: first, the centers of gravity and buoyancy must lie on one vertical line, and secondly, the focus should always be placed below the center of buoyancy.
Center of gravity and buoyancy may change when shifting items of equipment, such as breakage of the shoulder belt system. At the same time changes the normal position of the vehicle behind a swimmer and it will tend to bias toward the apparatus. In such cases, you should stop and stay under water to reach the surface.
Each athlete must be able to regulate their buoyancy and stability. Knowing your weight and body features, we can choose the weight of cargo for different conditions of release (with a single unit or in a diving suit) and to position equipment and supplies to the torso, then the athlete will not expend unnecessary muscular effort to maintain the necessary body position underwater. |
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