Balance and stability are separate concepts that are highly related. Balance is a person’s ability to control their equilibrium in relation to gravity only, whereas stability is your bodies ability to “return to a desired position or trajectory following a disturbance [to equilibrium].” Equilibrium is a state of no acceleration and can be static (without movement) or dynamic (moving at a constant velocity). Therefore, balance can be both static or dynamic, depending on whether the body is moving or not, but it must not have acceleration occurring.
If acceleration is occurring we are talking about stability, as our body needs to respond to the acceleration (whether the force is internal, from our own body, or external, from outside our body) and return to a desired position or trajectory. This could be as simple as changing direction, or as complex as completing a vault or responding to an attempted tackle from an opponent.
There are many processes involved in maintaining balance and stability in sport, and athlete’s who have to respond to a disturbance will often shift their body to better enable them to return to their desired position or trajectory. For example, when two forwards in rugby collide, they will often lower their body and spread their feet wider before contact in order to better enable them to remain stable.
The Preliminary PDHPE syllabus has three dash points for balance and stability, each of which influences the body’s ability to remain stable. The syllabus states:
Students learn about:
- balance and stability
- centre of gravity
- line of gravity
- base of support
Students learn to:
- apply principles of balance and stability to enhance performance through participation in practical workshops
Practice Exam Questions
Describe the relationship between line of gravity and base of support during a static balance pose in gymnastics. 3 marks
Explain how widening your base of support just before contact with an opposing player makes an athlete more stable. 5 marks
Analyse how an athlete in a specific sport might enhance their balance and stability. 8 marks
 NSCA (2012) NSCA’s guide to tests and assessments.