1.1: Skeletal and Muscular Systems Flashcards
Joint
an area of the body where two or more bones articulate to create human movement
Ligament
a tough band of fibrous, slightly elastic connective tissue that attached bone to bone
Articular Cartilage
smooth tissue which covers the surface of articulating bones to absorb shock and allow friction-free movement
Plane of Movement
the description of three dimensional movements at a joint
Movement Patterns
a description of the actions taking place at a joint - for example, flexion and extension of the elbow joint
Flexion
movement which decreases the joint angle, usually to the front of the body
Extension
movement which increases the joint angle, usually to the back of the body
Dorsi-flexion
movement at the ankle joint as the toes move up
Plantar Flexion
movement at the ankle joint as the toes move down
Abduction
movement of the limbs away from the midline of the body
Adduction
movement of the limbs towards the midline of the body
Horizontal Extension
movement of the limbs away from the midline of the body parallel to the ground
Horizontal Flexion
movement of the limbs towards the midline of the body parallel to the ground
Rotation
movement whereby articulating bones turn about their longitudinal axis in a screwdriver action
Tendon
a fibrous connective tissue that attaches a muscle to bone
Agonist
a muscle responsible for creating movement at a joint. also known as the prime mover.
Antagonist
a muscle that opposes the agonist providing a resistance for coordinated movement
Fixator
a muscle that stabilises one part of a body while another moves
Antagonist Muscle Action
paired muscle action. as the agonist muscle shortens to create movement, the antagonist lengthens to coordinate the action.
Isotonic Contraction
muscular contraction which changes length during its contraction. this can occur in two ways: concentric and eccentric contraction.
Concentric Contraction
muscular contraction which shortens while producing tension
Eccentric Contraction
muscular contraction which lengthens while producing tension
Isometric Contraction
muscular contraction which stays the same length while producing tension
Delayed Onset Muscle Soreness
pain and stiffness in the muscle which peaks 24-72 hours after exercise, associated with eccentric muscle contractions
Movement Analysis
analysis of the type and cause of bodily movement, including knowledge of the joint type, articulating bones, movement pattern, agonist and antagonist muscle action and contraction type
Motor Neuron
a nerve cell which conducts a nerve impulse to a group of muscle fibres
Motor Unit
a motor neuron and the muscle fibres stimulated by its axon
Action Potential
positive electrical charge inside the nerve and muscle cells which conducts the nerve impulse down the neuron and into the muscle fibre
Neurotransmitter
a chemical (acetylcholine) produced and secreted by a neuron which transmits the nerve impulse across the synaptic cleft to the muscle fibre
All-or-none law
depending on whether the stimulus is above a threshold, all muscle fibres will give a complete contraction or no contraction at all
Slow Oxidative Muscle Fibres
a type of muscle fibre rich in mitochondria, myoglobin and capillaries which produces a small amount of force over a long period of time
Fast Glycolytic Muscle Fibres
a type of muscle fibre rich in phosphocreatine which produces a maximal force over a short period of time
Phosphocreatine (PC)
a high-energy compound stored in the muscle cell used as a fuel for very high-intensity energy production (ATP-PC system)
Mitochondria
a structure in the sarcoplasm responsible for aerobic energy production
Myoglobin
a protein in the muscle responsible for transporting oxygen to the mitochondria
Aerobic work
low intensity, long-duration exercise in the presence of oxygen
Anaerobic work
high intensity, short-duration exercise in the absence of oxygen
Work : relief ratio
the volume of relief in relation to the volume of work performed
