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Home > Physical Education > Skills and Techniques > Mechanical principles

Physical Education

Mechanical principles


This revision bite help you understand the key movements and positions which affect skills and techniques.

Holding a balance

Balance is holding your body weight and centre of gravity over or through your base of support. Balance can be static, for example a headstand, or dynamic, for example when dribbling in football. It is easier to balance with a low centre of gravity and the bigger the base the easier it is to balance. To be balanced you should have your body weight above your base of support.

Base of support

Your base of support is the area which is covered by the parts of your body which are touching the ground. When you're standing still your feet provide the base of support.

Centre of Gravity

Your centre of gravity is your body's point of balance. It's close to your belly button. The lower your centre of gravity is, the more stable you are. When you put your centre of gravity outside your base of support, you lose your balance.

You hold your balance by tightening the muscles in your body. This is called body tension.

Centre of gravity in the centre of the human body, close to your belly button

Centre of gravity in the body

Loss of balance through shifting off centre of gravity by raising one leg

Shifting off centre of gravity


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