lectures 7 Flashcards
(37 cards)
Skeletal Function
- Support • Protect • RBC development • Nutrient storage • Frame for movement
Origin & Insertion
The muscle’s origin is attached to the more stable bone
• The insertion of the muscle attaches to the bone that moves when the muscle contracts
Joints
• Joints between bones allow movement • Range of motion (ROM) of the joints may be influenced by – Structure of the bone – Type of joint it forms – Muscle attachment points – Muscle size – Flexibility
Joint structure
- fibrous
- cartilnginous
- synovial
Fibrous
– Lacks joint cavity
– Limited or no movement
Cartilaginous
– Lacks joint cavity
– Limited movement
Synovial
– Has a joint cavity
– Movement variable
Synovial joints movement limited by
– Structure of the bone
– Strength & tautness of ligaments & tendons
– Size & arrangement of muscles that span
the joint
synovial joints
– Gliding – Hinge – Pivot – Condyloid – Saddle – Ball & Socket
Movements
• Flexion & Extension • Abduction & Adduction • Rotation – Internal & external rotation • Circumduction • Pronation & Supination
define flexibility
The range of motion (ROM) in a joint or series of joints
Factors affecting flexibility
Anatomical factors – Muscle • Muscle bulk • Muscle extensibility • Muscle strength – Connective tissue • Tendon, ligament & joint capsule – Bone structure • Sets limits on joint ROM
What factors influence flexibility?
- Age
– Gender
– Physical activity & lifestyle
– Environmental conditions
Flexibility - Age
• Decreases as childhood progresses to early
adolescence
• Increases slightly at late adolescence
• Decreases throughout adulthood
Flexibility - Gender
- Women are more flexible than men at all ages
– Less prominent bony landmarks
– Less muscle bulk
– Less connective tissue around joints
what is the value of flexibility
– Increase ROM in a ballistic movement – More aesthetic positions can be adopted – Prevention of injury?
Exceptions of flexibility in sport
High contact sport • Strong joint capsules around ankles, knees & shoulders are essential – These joints should not be ultra flexible like those of swimmers & gymnasts
what is important in swimming for flexibility
– Arm F-E necessary in Fly, Fr & Ba but not Br
– Foot D-P flexion necessary in Fly, Fr & Ba
– Thigh lat rot and thigh flex for Br
– exception - girl Ba too high arm flex - adduct
what is important in gymnastics for flexibility
– Arm F-E is important
– Thigh F-E necessary
– Thigh abduction is important
– Foot plantar flexion
what is important in diving for flexibility
– Trunk F-E is important – Trunk rotation – Foot plantar flexion – Above average arm F-E • But not as great as gymnasts
what is important in running for flexibility
– Thigh F-E is important to maximise stride
length
What are the 3 main
characteristics of
muscle?
• Creates movement - Contractile component
– Shortens when developing tension
• Can stretch - Extensibility
– Being able to stretch a muscle beyond its normal
resting length
• Will return to original shape - Elasticity
– Ability to return to its normal length after being
stretched
skeletal muslce
• Connected to bones via tendons • Contraction is voluntary – You must think about the movement for it to happen • Muscle shorten during contraction • Only pull – they do not push
Neuromuscular function
• Info is sent via an electrical impulse
• Nerves act in a similar manner as an electric cable
• When neural messages are sent to the muscle from the CNS they travel along motor neurons
• Information is sent back via sensory neurons
• Information sent from the brain
• Down the spinal cord
• To the target muscle
• For muscle contraction &
movement to occur
