Levers Systems & Human Movement Flashcards
What is a lever?
A lever is a simple machine consisting of a relatively rigid bar-like body (rigid bar, beam or limb) that moves on a fixed point (fulcrum) and capable of rotating about an axis.
What is a fulcrum?
A fulcrum is the point of support, or axis, about which a lever may be made to rotate around.
What are the 3 types of levers?
First-class levers
Second-class levers
Third-class levers
What is a first class lever?
A first-class lever is positioned with the applied force (effort) and the resistance (load) on the opposite side of the axis of rotation (fulcrum).
What is a second class lever?
A second-class lever is positioned with the resistance (load) in between the applied force (effort) and the axis of rotation (fulcrum).
What is a third class lever?
A third-class lever is positioned with the applied force (effort) in the middle of the resistance force (load) and the axis of rotation (fulcrum)
In the human body, which class of levers are most common?
third-class levers.
What does a third class lever promote?
A larger range of motion
Greater angular velocity
These lever systems are almost never in a complete state of balance.
What is human movement?
Human movement is the combination of the interaction of physiological systems to facilitate locomotion of the body or the manipulation of individual
limbs.
What is the anatomical position?
The anatomical position is the most basic and known
configuration of the human body and involve the
individual:
➢ Stood upright and facing forwards
➢ Arms are by the side with the palms facing forward
➢ The legs are straight and feet slightly apart from one
another and turned outwards slightly.
What is the fundamental position?
The fundamental position is similar to the anatomical
position, except the palms of the hand face inwards.
➢ Stood upright and facing forwards
➢ Arms are by the side with the palms facing inwards
➢ The legs are straight and feet slightly apart from one
another and turned outwards slightly.
What is the frontal/coronal plane?
The frontal (or coronal) plane is perpendicular to
the ground and divides the body into posterior (back)
and anterior (front) regions.
What is the transverse/axial plane?
The transverse (or axial) plane divides the body into
upper (superior) and lower (inferior) regions.
What is the sagittal/longitudinal plane?
The sagittal (or longitudinal) plane divides the body
into left and right.
What is flexion?
Flexion is the movement that decreases the joint angle, within normal range.
