Exam 2 Week 4 Flashcards
anaerobic training includes high intensity, intermittent bouts of exercise such as…
weight training, plyometric drills, speed and agility and interval training
the primary biological energy system that supply for the anaerobic exercise is the
phosphagen and fast glycolysis
can gains in the muscle occur without structural changes to the muscle? how
yes, because of neural adaptations
neural adaptations are the primary source of strength gains in the first ___ weeks of training.
8-10
after 10 weeks, _____ becomes the primary source of strength gains.
muscle hypertrophy
what other neural adaptations account for strength gains in muscle tissue (in the early stages of RT program, these account for more then 50% of gains).
- motor unit recruitment
- increased frequency of nerve firing rate
- improved synchronization of motor unit activation
- removal of inhibition
where are some potential sites for neuromuscular system adaptations
increased firing rate, GTO inhibits, increased stretch reflex, greater stimulation at the junction, for more action potentials
what is a motor unit composed of
a single alpha motor neuron and the muscle fibers it innervates
the alpha motor neuron determines what
if the muscle fibers are Type I, Type IIa or IIx
TF: motor unit distribution is largely genetically determines, with little change from across the lifespan
TRUE
describe the characteristics of a Type I motor unit
- cell body size
- # fibers it innervates
- function
- levels of aerobic endurance
small cell body, innervates less then 300 fibers.
high capacity for fine motor control and high level of aerobic endurance.
describe the characteristics of a Type II motor unit
- cell body size
- # fibers it innervates
- function
- levels of aerobic endurance
larger cell body, and innervates over 300 fibers. generate force, because of the more fibers and larger muscles. and poor aerobic endurance.
do motor units fire synchronously or asynchronously and why
async. because there are excitatory and inhibitory impulses
can you make gains in strength by improved synchronous contraction of the motor unit? why?
yes, because more units fire at the same time, so there is a faster muscle contraction and more force. also, EMG activity becomes higher too
type I fibers are for…
type IIa fibers are for…
type IIx fibers are for…
I: endurance
IIa: 1 mile run
IIx: short explosive events. like sprinting or explosive.
which fiber produces the most power
type IIx
TF: the order of recruitment of motor units is directly related to the size of the motor neuron
true
which fiber type gets recruited first, and why
Type I because they are lower threshold and have lower force capabilities.
TF: to get to the high threshold motor units the body doesn’t need to recruit the lower threshold motor units first
false, the lower threshold (type I) must be recruited first, to get the high threshold units.
TF: changes occur to the motor unit with prolonged anaerobic training
true
training may produce a small shift (<10%) in the percentage of…
Type I and Type II fibers.
how can motor units change?
there can be a subtype change. for example, with training, you can shift you IIa fibers to IIx fibers. based on your training needs.
what happens to type II fibers as we age? how is this clinically relevant
the fiber number of motor unit decreases, which accounts for the large percent of type I as we age. Your ability to produce contractions will decrease as you age.
what are some possible changes with anaerobic training at the neuromuscular junction
increased area of the NMJ.
increase in Ach receptors.
increased end plate perimeter, length and area with more receptors.
More dispersed synapses, to have a greater length of nerve terminal branches.
Type I fibers AKA
Type II fibers AKA (subgroups)
Type I: slow twitch or slow oxidative
Type II: fast twitch or fast glycolytic ANAEROBIC (IIa, IIx, IIc)
fill in the following for type I fibers:
- oxidative capacity
- glycolytic capacity
- contractile speed
- fatigue resistance
- motor unit strength
- high
- low
- slow
- high
- low strength
fill in the following for type IIx fibers:
- oxidative capacity
- glycolytic capacity
- contractile speed
- fatigue resistance
- motor unit strength
- low
- high
- fast
- low
- high
with heavy RT, how do all muscle fibers get larger
because more motor units are recruited in a sequential order, by their size, to produce high force.
how does CNS adaptation and recruitment help with speed and power in a movement
advanced powerlifters may not have the principle “recruit small first, then large”. they may just recruit large first, and get larger power or speed in the movement
hypertrophy
same number of fibers, but an increase in the CSA of existing fibers
what is hyperplasia
increase the number fibers, via longitudinal fiber splitting.
what are the two types of hypertrophy
transient (immediately after a workout because an increase in blood flow) an chronic (significant)
hypertrophy is a result of increased… from an increase in…. synthesis
number of sarcomeres and increase in the actin and myosin. thanks to an increase in protein synthesis
during exercise, PRO is broken down, but there is an increase in synthesis following exercise which is ___x more than at rest, and that window stays open for ___ hours
3-5x, 24 hours.
the process of hypertrophy requires 3 things, what are they
- increase in the synthesis of contractile proteins of actin and myosin in the myofibril.
- increase in the number of myofibrils within a fiber
- new myofilaments added to myofibril, so you get an increase in diameter.
can humans, who are under very high intensity strength training programs, haver hyperplasia. what may be the percentage of increased number of fibers?
yes, but super super rare, only if on the program for a long time, and exercise intensity is extremely high
5-10%
how does skeletal muscle adapt to anaerobic training (3)
- increasing its size
- facilitating fiber transitions, so that shift from subtypes, like Type IIa-Type IIx.
- enhancing its biochemical and ultra-structural components (fibers storing more creatine and glycogen for more ATP synthesis)
what happens to mitochondria density, capillary density and buffering capacity within the muscle with RT
decreased, decreased, (don’t need as much oxygen for the anaerobic training)
and increased buffering capacity.
high intensity strength training is more effective then low intensity strength training for… (3)
- anaerobic power
- timed task performance
- maintain strength after detraining.
what is the benefit of low intensity strength training
helps to improve the timing of performance.
anaerobic training produces significant structural changes to CT, including
bone, tendon and ligaments, fascia and cartilage
how can exercise programs be designed to stimulate bone formation
- use exercises that directly load the particular region of the skeleton
- use structural exercises to direct force vectors through the spine and hip, to allow the use of greater loads in training.
- overload the MSK system, and increase the load when you become accustomed
- vary exercise selection to change the distribution of the force vector to continually present a unique stimulus
RT in addition to what is most effective for increasing bone density
impact loading.
in the systematic review of physical exercise on BMD in older men, are changes specific to the region that is exercised
yes
what type of RT is needed to reduce the risk for developing osteoporosis
ongoing
how do you design a program to stimulate CT adaptations in tendons, ligaments and fascia,
full ROM for collagen.
high intensity loading
(low-mod intensity doesn’t change collagen)
forces exerted throughout the full ROM
TF: connective tissue and muscle are highly adaptable
true
for connective tissue, mechanical loading stimulates
collagen synthesis
a tendons CSA ____ in response to strength training
increases
tendon protein synthesis increases significantly after exercise, with a peak at ___ post exercise
24 hours
how can exercise be designed to promote healthy cartilage
- weight bearing forces, and complete ROM movements (to maintain tissue viability)
- aerobic to increase cartilage thickness
- strenuous exercise, does NOT cause DJD
does strenuous exercise appear to cause degenerative joint disease
no
an exercise program of step aerobic jumping, high impact aerobic and one flexion limited to 70 degrees showed what in post- menopausal women?
statistically significant increase in hyaline articular cartilage
what does acute anaerobic exercise do for ... CO SV HR Oxygen uptake SBS Blood flow to muscles
increases increases improves increases improves increases.
what does anaerobic exercise do to resting HR and BP
it may decrease it, or have no change .
how does anaerobic training affect ventilation
it doesn’t limit resistance exercise, and therefore is unaffected or only moderately improved by anaerobic training.
what affects may cross training of both RT and aerobic have on strength and power
you may not get as many gains, especially if you are training at a high intensity, with a high volume and high frequency
does heavy RT have adverse effects on aerobic power
no
what does circuit training do for capillary density
improves it
what does circuit training do to oxidative capacity and how
increases it, through an increase in citrate synthase activity
what does circuit training do to VO2 max
increases it
training bouts performed for ___ or less result in gains in strength, but not in enzyme activity
6 seconds
training bouts performed for ___ result in improvements in creatine kinase activity
30 seconds
do shorter or longer training bouts lead to improvements in short burst activities?
longer! because the longer improves the creatine kinase activity.
anaerobic training with ____ bouts increases activity of key glycolytic enzymes
30 seconds.
does sprinting lead to implements in fatigue, or power output with RT
no
an increase in glycolytic enzymes does what with the muscles ability
the muscle can maintain higher levels of tension for longer durations
what are the 6 performance improvements from anaerobic training
strength power local muscle endurance body composition flexibility aerobic capacity.
do strength gains occur rapidly in the beginning of a program for trained or untrained
untrained
are heavier or lighter loads more effective for fiber recruitment
heavier
the effects of training are related to the…
type of exercise used
intensity
volume
for power, heavy RT with (fast or slow) velocities of movement leads to improvements of max strength
slower
power training increases force output at (higher or lower) velocities and rate of force development
higher
with power, peak power output is maximized during the jump squat with loads corresponding to ___ to ____ of the squat 1RM?
30-60%
for the upper body, peak power output can be maximized during ballistic BP throws using loads corresponding t o___ to ___ % of the 1RM BP
46-62%
skeletal muscle adaptations to anaerobic muscular endurance training include (5)
- increase mitochondria and capillary number
- fiber type transition
- buffering capacity
- resistance to fatigue
- metabolic enzyme activity
RT can increase what type of mass
free fat mass
RT can reduce body fat by
1-9%
TF: RT leads to increases in lean tissue, metabolic rate, energy expenditure
true
can RT help with flexibility
yes
Does heavy RT affect aerobic capacity
not really, unless the person is initially very deconditioned
untrained people can experience increases in VO2 max ranging from
5-8%
what type of programs have been shown to improve VO2max
circuit, high volume, short rest periods
what are the psychological affects of overtraining
change in mood and attention, agitated, decreased desire to train, decreased joy from training
what is sympathetic overtraining syndrome
acute epi and NE increases beyond normal exercise induced levels. also. increases in HR, BP, RR, hard to WU
what are performance signs of overtraining. when does this occur?
performance decrements… this is the last to occur
what are two mistakes that can lead to overtraining
chronic use of high intensity or high volume (not enough recovery time)
and
too rapid progression (overuse)
what does an increased level of cortisol show
overtraining.
which is shown first… psychological or decrements
psychological
what is the definition of detraining
decrement in performance and loss of adaptations, after a bout of no exercise.
when can detraining happen
when you don’t exercise (sick, injured, holiday)
or
when you have a lower volume, intensity, frequency
