Chapter 6 - Muscular Anatomy Flashcards
What are the four unique characteristics of muscle tissue?
a) excitability
b) contractility
c) extensibility
d) elasticity
What is excitability in the context of muscle tissue?
Excitability is the ability of the muscle tissue to carry an electrical impulse called an action potential, which initiates the muscle contraction.
What is contractility in the context of muscle tissue?
Contractility is the response of the muscle cell to the electrical impulse. The muscle cell responds by shortening, pulling the two ends of the muscle towards each other.
What is extensibility in the context of muscle tissue?
Extensibility allows the muscle to be lengthened without damaging the tissue.
What is elasticity in the context of muscle tissue?
Elasticity allows the muscle to return to its resting length.
What are the types of muscle tissue?
a). Skeletal muscle
b). Cardiac muscle
c). Smooth muscle
What is the function of skeletal muscle?
It is muscle connected to the skeleton by being attached to two bones across a joint. These muscles produce the force required for human movement.
This chapter focusses on the Skeletal muscle tissue.
What is the function of cardiac muscle?
Cardiac muscle allow the heart to pump blood to the tissues.
What is the function of smooth muscle?
Smooth muscle is found in organs such as the digestive, urinary and circulatory system. When they contract, they do not exert much force.
How many skeletal muscles does the human body have?
The human body has over 600 skeletal muscles. Skeletal muscle is the most abundant type of of muscle in the body.
What are the main functions of the skeletal muscles
- provide force for human movement
- maintain upright posture
- generates heat to maintain constant body temperature
What is the structure of a skeletal muscle?
- made up of thousands of elongated rod-shaped cells called muscle fibers
- Muscle fibres are grouped into bundles of 10 to 150 muscle fibres in each bundle
HOw are the bundles of muscle fibres held together to form the muscle?
- Each bundle of muscle fibres are held together by the epimysium - which is the shiny outer layer of connective tissue surrounding the muscle.
- The layers of connective tissue amalgamate at the ends of the muscle to form the tendon.
- Tendons attach the muscle to the bone.
- Tendons and the epimysium (connective tissue) form the fascial tissue of the body.
Tendons attach
a). muscle to bone
b). muscle to muscle
c). bone to bone
a). Muscle to bone
What is the structure of a muscle fibre?
Made up of a lot of thinner fibres call myofibrils
What is the structure of a myofibril?
It is made up of sarcomeres - which are the basic unit for muscle contraction.
What is the structure of a sarcomere?
Composed of two proteins:
1). Actin
2) Myosin
When the muscle contracts, these two proteins slide along each other.
What are the types of muscle contractions?
1). Concentric contraction
2) Eccentric contraction -
3) Isometric contraction
What is a concentric muscle contraction and give an example?
when the muscle shortens (a bicep curl)
what is an Eccentric muscle contraction and give an example?
when the muscle lengthens (lowering phase of a bicep curl or elbow extension)
What is an isometric muscle contraction and give an example?
muscle exerts force to counteract an opposing force -
eg. holding a plank position (counteracting gravity)
eg. pushing your right fist into your left hand and exerting pressure from both arms)
What causes the skeletal muscles to contract?
- Skeletal muscles are controlled by the nervous system (the brain and the nervous system).
- They need a conscious decision by the brain to initiate a contraction.
- the decision is passed by the brain to the nervous system to initiate the contraction.
The nervous system is made up of two parts. What are they?
1). The Central Nervous System (the brain and spinal cord)
2)The Peripheral Nervous system (nerves that connect all parts of our body to the central nervous system).
What is the function of the Central Nervous System?
The Central Nervous sytem is the control centre - it receives information from the Peripheral Nervous System and prepares a response.
What is the function of the Peripheral Nervous System?
- It delivers information from the brain to our muscles. (when the brain tells you to move)
- It also delivers information from our body parts to the brain. (tells your brain when you have pain or feel something)
There are two types of muscle fibres in all muscles. What are they?
1). Slow twitch fibres
2) Fast twitch fibres
What are the characteristics of slow-twitch muscle fibres?
- Better for endurance
- Greater ability to use oxigen and resist fatigue (don’t get tired)
- produce ATP more slowly
- contract slowly and produce a smaller amount of force than fast-twitch fibres
- Work aerobically - use aerobic ATP
What are the characteristics of fast twitch muscle fibres?
- Contract quickly and produce a great deal of force but get tired quickly.
- Work anaerobically - use anaerobic ATP
Why are strong core muscles so important?
Core stability increases the ability of the body to produce power from the arms and legs. CLients with strong core muscles experience better body congrol, balance and coordination.
What are stabilizer muscles ?
They are core muscles such as transversus abdominis and intervertebral muscles that stabilize the spine during motion
Are stabilizer muscles made up of slow-twitch or fast twitch muscles?
Slow twitch muscles
What muscles enable mouvement in the core (spine and pelvis)?
Rectus abdominis, obliques, erector spinea, transversus abdominis
What muscles enable mouvement in the shoulder?
Pectorals and Deltoids
what major muscles enable mouvement in the shoulder girdle?
Trapezius and scapulae
What major muscles allows the shoulder to rotate?
Supraspinatus, infraspinatus, teres minor and subscapularis (SITS) - rotator cuff
What major muscles enable elbow mouvement?
biceps/triceps
What muscles enable mouvement in the wrist?
Flexor carpi radialis and extensor carpi radialis
What muscles enable mouvement in the hip?
adductor, gluteus and hamstrings
What muscles enable mouvement in the ankle?
Tibialis anterior, tibialis posterior
What’s another name for rotator cuff?
Supraspinatus, infraspinatus, teres minor and subscapularis (SITS)
Explain what is meant when we say that muscles are an adaptable tissue?
With proper training muscles can grow stronger. (Hypertrophy)
If muscles are not used on a regular basis, they can become weaker (atrophy).
What is muscular strength?
The maximum amount of force that a muscle or muscle group generate.
What is muscular power?
it is the explosive aspect of strength - it is the product of power and mouvement
What is muscular endurance?
The ability of a muscle to exert force repeatedly over time.
What is the FITT formula for muscle training?
Frequency = 2 or more resistence traing sessions per week
Intensity = the higher the number of repetitions, the lower the load. Choose a number of reps the client can complete with proper technique
TIme = depends on clients’ personal goals. To make workouts more time efficient, modify routines for clients by using split programs
Type =
List three types of muscle tissue?
- Skeletal muscles - are attached to the bones - resistence training strengthens these muscles
- Cardiac muscles - make up the walls of the heart - cardio respiratory exercises strengthens these muscles
- Smooth muscles - make up the walls of hollow organs - eg stomach, intestines, bladder, blood vessels, etc.
What is the core region and why is important?
The core is from the rib cage and diaphram to the pelvis.
A stable core provides the arms and legs with a solid anchor to produce force and movement for every day activities and for fitness training.
What type of muscular contraction is responsible for elbow flexion during a bicep curl exercise?
a. Eccentric
b. Concentric
c. Isometric
d. none of the above.
b. concentric
The rotator cuff is described by the acronym SITS which stands for
a). supraspinatus, interosseous, teres minor, and sartorius
b). subscapularis, interosseous, trapecius and serratus anterior
c). supraspinatus, infraspinatus, teres minor and subscapularis
d). supraspinatus, infraspinatus, trapezius, and subscapularis
SITS = supraspinatus, infraspinatus, teres minor and subscapularis
The stabilizing muscles are composed primarily of
a). a mixture of fast and slow twitch muscles
b). fast-twitch muscles
c). slow twitch muscles
d) none of the above
slow twitch muscles
Seeing changes happen quickly can provide great motivation to beginners, but the rate of change in muscle recruitment tends to slow significantly after the first
a). 2 weeks
b). 4 weeks
c). 8 weeks
d). 10 weeks
8 weeks
What is meant by muscular hypertrophy?
Muscular hypertrophy is the increase and growth of muscle cells through exercise.
