Chapter 9 - Muscular Training Flashcards
Skeletal System Considerations
- 206 bones, most of which are paired
- Bones give support to soft tissue, provide attachment sites for most muscles
- Skeleton stores minerals, produces blood cells
- bones composed of: cortical (outer hard, 75%), trabecular bone (inner honeycomb, 25%)
- Wolff’s Law - when forces are applied, more layers of bone are created causing more density
Axial Skeleton
- Include: skull, vertebral column (33 vertebrae, sternum & ribs
- Bones that support the body and CNS
Vertebrae Contains
Cervical - 7 Thoracic - 12 Lumbar - 5 Sacral - 5 (fused) Coccyx - 4 (fused)
Appendicular Skeleton
126 bones of the upper and lower limbs and shoulder and pelvic girdles.
Three Main Types of Joints
- Synovial - most joints, freely moveable
- Fibrous - held tightly, little or no movement
- Cartilaginous - connected with cartilage, little or no movement
Synovial Joint Characteristic Traits
- articular cartilage
- articular capsule
- synovial membrane
- synovial fluid
Planes of Movement at Synovial Joints
- Uniaxial or uniplanar - one plane, hinge joints, elbow
- Biaxial or biplanar - 2 planes, knee, hand, wrist
- Multiaxial - hip, thumb, shoulder
Synovial Joints - movement type
- Gliding - rib and vertebra
- Angular - Flexion, Extension, Abduction, Adduction
- Circumduction - all 4 angular movements (shoulders & hips)
- Rotation
Inversion vs Eversion
- Inversion - foot tipped up on medial side
2. Eversion - foot tipped up on lateral side
Central Nervous System & Peripheral Nervous System
- CNS - Brain & spinal cord, receives sensory input from PNS, control center
- PNS - Nervous structures (nerves) outside of CNS
Sympathetic Nervous System & Parasympathetic Nervous System
- SNS - activated under stress or emergency - Fight or Flight
- PNS - controls normal functions - Rest and Digest
Neuron components
Cell body - Nucleus and Dendrites (many, sends pulses into cell) & Axon (only one, sends pulses away, attaches to muscle)
& Myelin sheath (insulator that covers Axon)
Autogenic Inhibition
- An automatic reflex relaxation caused by stimulation of the Golgi Tendon Organ (GTO)
- A muscle can be stretched more fully and easily when the the GTOs are stimulated
- Static Stretching
Reciprocal Inhibition
- The reflex inhibition of the motor neurons of antagonists when agonists are contracted.
- PNF
- For ROM improvement it is important to initiate a stretch immediately following inhibition of the muscle spindle due to its rate of recovery.
Muscle Tissue Functions
- Voluntary
2. Involuntary
Three Types of Muscle Tissue
- Cardiac - heart, involuntary
- Smooth - stomach, intestines, blood vessels, involuntary
- Skeletal - exerts forces on bones to move & stabilizes them, striated
Muscle Organization
Tendon - attaches to muscle at origin
Epimysium - outermost layer of connective tissue
Bundles of muscle - each surrounded by perimysium
Individual muscle fiber - striations, each surrounded by endomysium
Sarcomere - inside muscle fiber
Myosin - inside sarcomere, thick myofilaments
Actin - inside sarcomere, thin myofilaments
Muscle Fiber Types
- Slow Twitch - Type 1, lots of mitochondria, surrounded by more capillaries, more myoglobin - makes these muscles resistant to fatigue, sustains aerobic function, more efficient
- Fast Twitch - Two sub-types, Type IIx and Type IIa.
- Type IIx - (fast-glycolytic) contain little mitochondria, little aerobic capacity, can only sustain effort for a few seconds. Largest & fastest fibers & create most force but less efficient.
- Type IIa - (intermediate or fast oxidative glycolytic) intermediate between slow & Type IIx. Can sustain effort for up to 3 minutes. They are highly adaptable with training.
Proprioception definition
The sense of knowing where the body is in relation to its various segments and the external environment.
Determining factors in which type of muscle fibers a person has
Genetics, hormones, activity and exercise habits influence the percentage of fast or slow twitch muscles.