Factors Increasing Equilibrium

Factors Increasing Equilibrium

Several factors decide how much equilibrium — how much stability — a body has. An athlete who understands them can set up a far more stable position. The CBSE Class 12 Physical Education textbook lists the following factors that increase equilibrium:

• Centre of gravity within the base of support — the body is stable only while the line of the CG falls inside the base; instability increases as the CG moves towards the edge of the base.
• A larger base of support — a wider base makes the body harder to upset.
• Greater body weight — a heavier body (or object) resists being moved.
• A lower centre of gravity — keeping the CG low raises stability.
• Anticipating an oncoming force — place the CG towards the side of the base that is expected to receive the force, and extend the base of support in the direction of the expected force.
• Greater friction between the body and the surfaces it is in contact with.
• Rotation about an axis — a moving (rotating) cycle is far easier to balance than a stationary one.
• Kinaesthetic physiological functions — the vestibular system, vision, touch and kinaesthetic awareness all help the body sense and correct its balance.

Examples: the balanced stance a batsman holds in cricket, the set position of a sprinter on the starting block, and the wide, low stance a wrestler takes up are all everyday applications of these factors.

Guiding Principles to Determine the Degree of Stability

The factors above can be summed up as five guiding principles that decide just how stable a position is, each with a clear sporting application:

1. The broader the base, the greater the stability. Widening the base of support improves stability — for example, spreading the feet in the direction of movement, or using both hands and feet (as in a sprint start) to create the widest possible base.
2. Body weight is directly proportional to stability. A heavier athlete or object is harder to move; this is exactly why combative sports such as judo, wrestling, taekwondo and boxing are organised into bodyweight categories.
3. The lower the centre of gravity, the higher the stability. Players lower the CG by bending — a runner bends the knees to stop sooner and more efficiently, a wrestler half-sits to hold his ground, and a shot-putter bends the knees at the finish to avoid fouling. …