Types of Motions
Joints and their Movements- Neck - flexion/extension, lateral flexion, rotation
- Acromioclavicular - elevation, depression
- Glenohumeral - extension, abduction, adduction, rotation - internal and external
- Scapula - protraction/retraction
- Elbow - flexion/extension, pronation/supination
- Wrist - flexion/extension, radial and ulnar deviation
- Fingers - flexion/extension, abduction/adduction.
- Hip - flexion/extension, abduction/adduction, rotation - internal and external
- Knee - flexion/extension
- Ankle - plantarflexion/dorsiflexion, inversion/eversion
- Toes - flexion/extension
Movement occurs within the human locomotor system through strength, force, and power
created by the musculoskeletal system. The contractile tissue, non-contractile tissue, joints, and
skeleton are used to create levers to maximize and produce strength, force, and power that are
more efficient for motion or work.
Understanding the biomechanics of the musculoskeletal system requires knowledge of the
anatomy and planes of movement, as well as the force and lever systems the human body produces
and uses to its advantage. The skeletal system provides the framework and support needed to
perform the various movements occurring during exercise or sport. Contractile tissue moves the
bones and creates the necessary force and power of the athlete. The skeleton is a lever system
controlled by the muscles.
Laws of Motion
- Newton’s First Law of Motion: “Law of Inertia”
“Every object in a state of uniform motion tends to remain in a state of motion unless
acted upon by an external force applied to it.”
There are two types of inertia:- Static: the mass you are working against doesn’t want to move.
An example would be lifting a weight.