Encapsulated in tendon fibers near junction of muscle and tendon fibers.
What does the Golgi Tendon Organ sense?
Amount of tension in a contracted muscle
What is autogenic inhibition?
The inhibatory signal the CNS sends to the muscle when tension is too high
Does strength training increase or inhibit the activity of the golgi tenton organ?
What are joint receptors?
Proprioceptors in the joints that relate body position awareness to sensory cortex
What are cutaneous receptors?
Sensors that relate pressure, temperature, and tissue damage to the sensory cortex
What structures in the labyrinth of the ear help with body position awareness?
Semicircular canals and utricles (hair cells)
What do semicircular canals do in relation to proprioception?
The fluid inside the semicircular canals moves and responds to angular movement (going in circles)
What do utricles do in proprioception?
They respond to linear and gravitational movement to maintain center of gravity
What is the upper cervical neck reflex?
Remnant from infancy; dorsiflexion facilitates extension of limbs while ventriflexion facilitates flexion
What, in order, are the five steps of a reflex loop?
(1) Receptor senses stimulus
(2) Action potential is sent down afferent neuron to spinal cord
(3) Afferent neuron synapses with a central integrating system in the interneurons
(4) Action potential is sent to both the motor cortex and down the efferent neuron
(5) The motor cortex acknowledges the need to move, and efferent neuron has already innervated the effector organ and initiated movement"
What is neuromuscular patterning?
The patterning in the brain of proprioceptive reflexes for skilled movements, ie touch-typing
How does the "centipede's dilemma" relate to neuromuscular patterning?
When you think about what you are doing in a movement that has been patterned, the conscious direction of the motor cortex interferes with the smooth function of the subcortical levels that have been patterened. IE, the centipede can't walk when it stops to think about how it coordinates all those legs"
Which has decreased over time, kcal in or kcal out?
kcal out in the form of decreased physical activity
What is the equation for total body mass?
TBM = Fat Mass + Lean Body Mass
What are 7 functions of fat in the human body?
(3) Greatest capacity of stored energy
(4) Cell membrane structure
(5) Myelin sheaths of nerves
(6) Absorbs fat soluble vitamins
(7) Backbone for steroid hormones
How does hydrostatic weighing work?
Constituents are separated based on their relative specific gravity compared to water. Fat floats, lean body mass sinks.
What are the specific gravities of fat mass and lean body mass?
Fat mass is ~ 0.9, Lean Body Mass is slightly > 1.0
What is the term given to the activity of measuring the body?
What 4 types of body composition measurements are most commonly used?
Skinfolds, girth, height, and weight
How does one calculate BMI?
Weight divided by height squared
What is a shortcoming of BMI?
Muscle weighs more than fat, so those with high LBM may register as obese
What are the two body types associated with male and female?
Male: Apple or Android \
Female: Pear or Gynoid
Which body type is associated with high plasma insulin?
Which body type is associated with lower triglyceride lipase activity, and why?
Gynoid, because there is not a layer of fat creating pressure on the liver
Which body type is associated with lower HDL cholersterol counts?
How does bioelectrical analysis work?
A small charge in introduced to subject. Fat insulates while lean body mass conducts. The amount of electrical impedence indicates fat to lean ratio.
What are some shortcomings of bioelectrical analysis?
It tends to underestimate fat mass for very obese individuals and overestimate fat mass for very lean individuals, and dehydration leads to overestimation of fat mass in all individuals
How does infrared interactance work?
Infrared beams refract and reflect differently off lean and fat body mass and these reflections and refractions can be measured to obtain a fat to lean ratio
What are some shortcomings of infrared interactance?
Only uses one test site and fat distribution is different across the body
What are the four compartments in the 4-compartment model, and how are they categorized into 2 compartments?
Water, protein, and bone mineral make up the lean body mass compartment, and fat makes up the fat mass compartment
What is the stupid fat burning zone?
The fiction that working at less than max heart rate is just as beneficial as working at max heart rate
What are 4 benefits of working out as hard as possible?
Greater aerobic fitness, reduced chance of CHD, improved vigor, and more total calories burned
When should a person NOT work at maximum intensity?
When biomechanics restricts doing so safely (joint considerations) or when a person is only just beginning training
What are the three types of muscle? Which types are consciously controlled?
Cardiac, smooth, and skeletal; only skeletal is consciously controlled
What is the smallest functional contractile unit of skeletal muscle?
Does muscle have a good or poor blood supply?
Muscle fibers have an excellent blood supply that penetrates the entire fiber system
What is the most important element in muscle contraction?
How does a muscle perform work?
Sarcomeres shorten, which pulls on the tendons attached to bones
What are the two types of concentric muscle action?
Allodynamic (with a sticking point at 100% recruitment) and isodynamic (100% recruitment at all angles in range of motion)
What muscle action results in no visible joint angle change?
What muscle action results in negative action?
Eccentric, or lengthening
Which muscle action requires less oxygen and less neural recrutiment?
How is calcium maintained in the sarcoplasmic reticulum?
It is constantly returned to the SR by the magnesium-ATPase active transport pump and bound by Calsequestrin for storage
What are the 7 steps in sliding filament theory?
(1) Nerve stimulates membrane potential change
(2) Transverse tubules conduct impulse to interior of muscle fibers
(3) Calcium is released from terminal cisternae
(4) Calcium binds to troponin
(5) The bound troponin changes the shape of tropomyosin
(6) Tropomyosin's shape change exposes the myosin binding sites on actin
(7) Myosin bridges attach to actin to create muscular force
What are the seven steps of sliding filament theory called?
What are the two contractile muscle proteins?
Actin and myosin
What are the two muscle regulatory proteins?
Troponin and tropomyosin
What causes the myosin head to bread away from actin?
Phosphorylation of ATP
How long will excitation contraction coupling continue?
As long as the stimulus, calcium, and ATP are present
What is the energy transduction that occurs in muscle contraction?
Chemical (ATP) to mechanical (muscle contraction)
What element is required to pump Calcium back into the sarcoplasmic reticulum?
What are the two types of muscle fibers?
Type 1, Slow oxidative (slow twitch red) and Type 2, Fast glycolytic (fast twitch white)
What determines the percentage of each muscle fiber type in a muscle?
Genetics and the specific muscle group a muscle is part of
Can the percentage of the two muscle fiber types be altered?
No, but metabolic capacity of one type or the other can be increased by specific training
Which muscle fiber type is high in ATPase?
Which muscle fiber type is high in mitochondrial-ase activity?
Which muscle fiber type is high in glycogenolytic activity?
Which muscle fiber type is high in glycogen content?
Both type II and I are the same
Which muscle fiber type is high in myoglobin content?
Which muscle fiber type has high capillary density?
Which muscle fiber type has a fast contraction speed?
Which muscle fiber type has a low activation threshold?
Which muscle fiber type is high tension?
Which muscle fiber type is slow to fatigue?
What is a Type II a muscle fiber?
A fast oxidative glycolitic fiber, which is more fatigue resistant and has more oxidative qualities than a fast glycolitic fiber, but not as much as a slow oxidative fiber"
Which muscle fiber is used for endurance?
Which muscle fiber type has high aerobic capacity?
Which muscle fiber type can metabolize lactic acid?
Which muscle fiber type has a low force generation?
Are Type I fibers arranged in large motor groups or small motor groups?
Small motor groups, which gives them fine motor control
Which muscle fiber type is found in "power" muscles?
What is unique about type II a muscle fibers?
They can be trained to take on either type I or type II characteristics
Why does someone get stronger, but not get bigger, during their first few weeks of training?
Is hyperplasia possible in humans to create a stronger individual?
When can satellite cells mostly be found in muscles?
When beginning training and during rehabilitation
How do satellite cells repair damaged tissue?
Satellite cells replicate, becoming myoblasts. The myoblasts fuse to become multinucleated and grow into mature muscle fibers"
What is the strength of a muscle?
4kg times cm cubed
Are muscle fibers in males or females stronger?
Same strength, but males have more
"What do isotonic, dynamic, and phasic muscle actions all have in common?
All are names for concentric muscle action
When does a muscle have the poorest leverage?
At 90 degrees to gravity
What does DOMS stand for?
Delayed onset muscle soreness
What is involved in DOMS?
Increased perceived soreness for 24-72 hours after exercise, increased markers on muscle damage, increase markers of connective tissue damage, increased ultrastructural damage"
What are two markers of muscle damage?
Creatine kinase and lactic dehydrogenase
What is a marker of connective tissue damage?
Rank the three types of muscle action from greatest force capacity to least
Eccentric, isometric, concentric"
What is the speed of muscle action?
Response time = Reaction time + Movement time
what is muscle reaction time?
The time elapsed from application of stimulus to the first detected muscle contraction
What is movement time?
The time span between the first muscle contraction and the completion of the movement
What is the tension-length curve?
As a muscle gets shorter or longer, it cannot produce as much tension and therefore cannot produce as much force"
What relationship does calcium ion have to force production in a muscle?
The more calcium present, the more force can develop"
What are the four types of chemical messengers in the body?
Paracrine, endocrine, neurocrine, and neuroendocrine"
Which messenger class has local action, acts by diffusion, is fairly slow, and releases a nonspecific chemical for which no receptors are required?
Which messenger class has local and distant action, acts rapidly by synaptic transmission, and releases abundant neurotransmitters for which there are few specific receptors on the target tissue?
Which messenger class has a distant locus of action, is blood borne and acts slowly, and releases very small amounts of hormones for which there are many specific receptors on the target tissue?
What are the two types of hormones?
Protein, peptide, and amino acid hormones (pituitary and adrenal medulla releases); lipid hormones (including prostaglandins) (released by adrenal cordex and gonads)"
What is second-messenger theory?
Many hormones cannot get past cell membrane, so they bond to cell membrane and change permeability to a second messenger that can then diffuse through membrane or enter membrane through channels that the hormone turns on"
What is the significance of Cyclic AMP?
Serves as a second messenger that activates other enzymes that result in glycogen breakdown and glucose availability
What are intracellular hormones?
Lipid-soluble hormones that can pass through cell membranes to bind to receptors in the cell cytoplasm