Chapter 4 Flashcards
What are the three types of muscle?
Cardiac, smooth, and skeletal muscles.
Uniarticular?
Muscle origin and insertion span one joint.
Multiarticular?
Muscles whose origins and insertions span two joints.
Agonist?
Muscle contracting to cause movement?
Purpose of Antagonists?
Opposes agonist, stabilize joint, decelerating movements, reduce risk of injury.
Fixator?
Also called stabilizer and it steadies a joint.
Neutralizer?
When a muscle eliminates the movement of a multiarticular muscle.
Breakdown of muscle structure?
- Epimysium
- Muscle belly
- Perimysium
- Fascicle
- Endomysium
- Muscle fiber
- Sarcomere (portion of muscle between two Z-lines)
- Actin and mysin
Organization of a muscle fiber?
- Sarcolemma (cell membrane)
- T tubules (transfer action deeper)
- Sarcoplasm (liquid surrounds myofibrils)
- Mitochondrion, terminal cisternae, and nucleus
Sarcomere?
Z-line to Z-line and functional unit of muscle fiber.
Stages of muscle contraction?
- Excitation-contraction coupling
- Cross-bridge cycling
- Relaxation
Excitation-contraction coupling?
Electrical discharge stimulates chemical changes and removes barriers and allowing for muscle contraction to take place.
Cross-bridge cycling?
The process of myosin heads pulling and releasing asynchronously. (Tug of war, pulling rope and regripping and pulling again)
Relaxation?
Reduced neural stimuli cause chemical changes causing the blocking of actin active sites and myofilaments return to resting.
Twitch?
Contraction of muscle.
Summation?
Multiple twitches.
Tetanus?
Maximal force production of a muscle.
Myogenesis?
Muscle fiber formation.
When do muscles grow in training?
During recovery phase. Lifting causes the stimulus for them to grow but actually breaks them down.
Why would muscles get smaller with aerobic training?
Lower ST fiber area increases oxygen kinetics with muscle.
What type of muscle fiber can grow bigger and faster?
Fast twitch, slow twitch will still grow though.
What type of training produces better gains?
ECC.
Occlusive Resistance Exercise?
Blood flow mechanically reduced which results in pronounced lactate and growth hormone response. (Similar results in bodybuilding workouts)
Do you need to damage muscles to make them grow?
No. Stimulus still occurs.
Hyperplasia?
Longitudinal splitting of existing muscle fibers (new fiber development).
