Understanding Force, Inertia, and Fitness Testing
Understanding Force and Motion
Force: A push or pull action applied upon an object.
Inertia: An object in motion stays in motion at the same speed and in the same direction, and an object at rest stays at rest unless acted upon by an external force.
Force (N) = mass (kg) x acceleration (a)
- Mass: The quantity of matter in a body.
- Acceleration: Rate at which an object changes speed.
Acceleration and Newton’s Third Law
Acceleration: An object will accelerate when acted upon by an external force. The acceleration of the object is proportional to this force and is in the direction in which the force acts.
Newton’s Third Law: For every action, there exists an equal and opposite reaction.
Examples of Forces in Sports
Forces applied during sports examples:
- A force can cause an object/body at rest to move: The racquet will remain at rest until the player applies a force to move it backwards to cause a backswing to prepare to hit the ball.
- A force can cause a moving object or body to change direction: When the ball comes back from the wall, the squash player’s racquet will hit the ball and exert a force to change the direction of the ball.
- A force can cause a moving object/body to accelerate: When squash players need to increase their speed to run across the court, they will apply a greater force against the ground. This causes them to accelerate.
- A force can cause a moving object to decelerate: As players reach the ball, they need to slow down. They will apply force to the ground in the opposite direction to the one they are running in.
- A force can cause an object/body to change its shape: When the ball hits the wall/racquet, it will deform as it transfers momentum from one direction and transfers it to the new direction it is forced to travel in.
Applications of Force
Applications of Force:
- Gravity: The force that attracts a body towards the center of the earth, or towards any other physical body having mass.
- Muscular force: A push or pull applied to an object, provided by muscular contraction.
- Air resistance: The frictional force that air applies against a moving object.
- Ground reaction force: The reaction to the force that the body exerts on the ground.
Fitness Testing Components
Cardiovascular Endurance
Cardiovascular endurance:
12-minute run test: In this test, you run or walk as far as you can in 12 minutes. The fitness level is judged by comparing the distance run to established norms for the test.
Speed
Speed – 30 m sprint
The 30 m sprint measures how fast you can run over a short distance. This is a maximal test, as you need to run as fast as you can.
Flexibility
Flexibility: Sit-and-reach test
This test measures suppleness in the back and hamstrings. You sit on the floor with your legs fully extended, feet flexed, and hands touching the sit-and-reach box. You stretch forward with both hands, keeping your legs straight and sliding your palms along the box. The distance your fingertips reach beyond your toes is the measurement.
Muscular Endurance
Muscular endurance: Multi-stage abdominal conditioning test.
Muscular endurance is when a muscle or group of muscles works continuously without tiring for a long period of time. You will require: a mat, a stopwatch, and a partner to record the number of sit-ups. Over a 30-second period, perform as many sit-ups as you can. Your partner will time you and keep count. Then use a table to identify your level of muscular endurance.
Power
Power: Vertical jump test
Facing the wall, stretch both arms above your head with your hands side by side so that your fingertip level while standing can be marked on the wall or jump board. Then turn sideways to the wall and, with both feet together, jump as high as you can, touching the wall/jump board with the fingertips of one hand.
Strength
Strength
Skill-Related Fitness
Four Skill Related:
Agility
Agility – Illinois agility run test:
Start face down behind the starting line, with your chin on the floor. On the command ‘Go’, stand up and run as fast as you can around the cones, following the pathway. The measurement is the time taken to complete the run.
Balance, Coordination, and Reaction Time
Balance, Coordination, Reaction.
VO2 Max
VO2MX: Volume of oxygen that can be consumed exercising at a maximum capacity.