Chapter 5 Flashcards
characteristics of anaerobic training
high intensity
requires rapid regeneration of ATP
anaerobic alactic system
phosphagen system
aka
creatine phosphate system
anaerobic lactic system
glycolytic system
components of “increased neural drive”
- increased agonist recruitment (more motor units)
- improved neuronal firing rates (increased firing rate)
- greater neural discharge synchronization (activation of more muscles concurrently)
size principle of motor recruitment
muscles are activated sequentially in a continuum from low to high size motor units.
this means maximal force will recruit all units, not just Type II suited for power or speed
selective recruitment
- an exception to the size principle
- when great force is required at a high speeds, trained athletes may recruit larger fast twitch motor units first
Neuromuscular Junction adaptations to resistance training
high intensity training led to
- greater area covered
- greater nerve terminal length
- greater acetylcholine receptor dispersion
myotatic reflex
the reflex of the muscle spindle to increase force production when stretched
resistance training increases the force this reflex provides without added energy
electromyography (EMG)
helps examine neural activation in muscle
cross-education
training one limb can increase strength in the other thanks to neural adaptations
bilateral deficit
the sum/total force of 2 limbs acting separately is greater than when working together
bilateral facilitation
an increase in voluntary activation of agonist groups when working together
occurs in the stronger/trained.
hypertrophy
enlargement of muscle fiber cross sectional area
titin
structural protein
nebulin
structural protein
myogenesis
muscle protein synthesis and subsequent growth
sequence of protein synthesis
- water uptake
- noncontractile protein synthesis
- contractile protein synthesis
factors determining magnitude of post-exercise acute increased protein synthesis (for 48 hours)
- carb and protein intake
- amino acid availability
- nutrient intake timing
- mechanical stress of workout
- muscle cell hydration level
- anabolic hormone and receptor response
mechanical factors of exercise determining magnitude of hypertrophy
- heavy loads
- eccentric muscle action
- low to moderate volume
- novel modalities
exercise factors contributing to metabolic inducement of hypertrophy
low to moderately high intensity
high volume
short rest
hyperplasia
increase in number of fibers
not shown to occur in humans. only animals
muscle fiber type continuum from most oxidative to least
I, Ic, IIc, IIac, IIa, IIax, IIx
muscular structural changes from resistance training
- greater pennation angle
- greater fascicle length
other muscular adaptations to resistance training
- greater pH buffering capacity
- greater CP and ATP storage
- increased myofibrillar volume
2 mechanisms of hypertrophy
increase of myofilaments in myofibril
or
increase in number of myofibrils
osteoblasts
cells that rebuild bone after mechanical loading
function by manufacturing and secreting protein (collagen) in spaces between bone cells
hydroxyapatite
collagen proteins crystalized into calcium phosphate for bone growth
trabecular bone
spongy inner bone
cortical bone
hard compact outer bone
minimal essential strain (MES)
& quantification
the stimulus threshold that initiates new bone formation
about 1/10 the force it takes to fracture the bone
bone mineral density
&what can increase it
quantity of mineral in a given area of bone
resistance exercise can increase it due to force of weights and strain of muscle pulling on bone
mechanical variables of load for stimulating bone growth
specificity of loading speed of loading direction of loading exercise selection volume progressive overload variation
specificity of loading
directly loading the region of interest
considerations of exercise selection for bone growth
multi-joint exercises are best because they allow for heavier loads on more bones
progressive overload
continuously placing greater demands than normal on skeletal/muscular system
stress fractures
microfractures in bone due to structural fatigue
importance of exercise variation for bone growth
helps bone grow to resist forces from more angles
procollagen
collagen precursor secreted by fibroblasts
indicator of collagen formation
concentration of enzyme that cleaves collagen end so it can align with other collagen molecules
microfibril
bundle of collagen filaments
cross-linking
strong chemical bond between adjacent collagen molecules
elastin
elastic fiber found in ligaments
ligament/tendon adaptations that contribute to size/strength increase
- fibril diameter increase
- more covalent crosslinks within fiber
- more fibrils
- increased fibril backing density
muscle fiber type changes as a result of anaerobic exercise
type IIx turns to IIa
functions of articulating cartilage
- provide smooth surface for articulating joints
- absorbs forces directed through joint
- aid attachment of connective tissue to skeleton
mechanical factors that stimulate connective tissue adaptations
high intensity through full range of motion for tendons, ligaments, and fascia
moderate intensity through full range of motion for articulating cartilage
hyaline cartilage
articulating cartilage at end of bones
fibrous cartilage
tough cartilage in spine and tendon-bone attachment sites
importance of movement for joint health
movement drives nutrients from synovial fluid into articulating cartilage
acute anaerobic hormone response to exercise
increases in testosterone, IGF, GH, & catecholamines
benefit of chronic changes to acute hormonal response
chronic changes will help the body sustain prolonged higher intensity exercise
chronic changes in resting hormonal concentrations
none.
this is good because it avoids downregulation
acute response to resistance training of androgen receptors
upregulation within 48-72 hours
initial downregulation before upregulation
acute cardiovascular response to resistance training
- increased cardiac output
- increased stroke volume
- increased heart rate
- increased oxygen uptake
- increased systolic blood pressure
- increased blood flow to active muscles
reactive hyperemia
an increase in blood flow to working muscles immediately following cessation of activity
(ex. resting after a set)
factors determining magnitude of accute cardiovascular response to exercise
intensity, volume, muscle mass involved, rest period length, contraction velocity
chronic cardiovascular adaptations at rest
4
- resting blood pressure reduction
- increased left ventricular wall thickness
- resting heart rate reduction
- bigger left atrium
chronic adaptions of cardiovascular system to acute response to resistance training
- lower heart rate, blood pressure, and myocardial oxygen consumption during work
- greater stroke volume & cardiac output
rate-pressure product
HR x systolic blood pressure
ventilatory equivalent
ratio of air ventilated to oxygen used by body
aerobic + anaerobic training results
C,S,E groups
C - IIx to IIa, size increase IIa
S - increased 1RM most. IIx to IIa, size increase I, IIc, IIa
E - some IIa to IIc, size decrease I, IIc
best way to decrease incompatibility of anaerobic and aerobic training
more rest between workouts
anaerobic + aerobic training impact on power & strength
decreases power, no impact on strength
% of 1RM in squat training to maximize peak power
56%
overtraining
& recovery times
accumulation of training stress resulting in long term decrease in performance
recovery can take weeks to months
overreaching
aka
function overreaching (FOR)
(& recovery time)
excessive training that leads to short term decreases in performance
recovery within days or weeks
can be part of a planned regimen to build up tolerance to stress and increase strength and power
(NFOR) nonfunctional overreaching
&recovery time
a state of stagnation and decrease in performance for weeks or months
(OTS) overtraining syndrome
& recovery time
a state of malfunctioning in several biological, neurochemical, and hormonal regulating mechanisms
recovery can be 6 months to years
sympathetic overtraining syndrome
& who it happens to
increased sympathetic activity at rest
happens to younger athletes training for speed or power
parasympathetic overtraining syndrome
& who it happens to
increase in parasympathetic activity at rest and during exercise
aka
suppressed physiological systems throughout the body
aerobic-endurance athletes
causes of overtraining
high volume, high intensity, high frequency, limited rest & recovery
hormonal markers of volume overtraining
cortisol increase
resting leutenizing hormone decrease
free testosterone decrease
reduction in acute testosterone increase due to exercise
how long must endocrine response be monitored to serve as potential OTS marker
1 week
endocrine response to NFOR in trained athletes
large sympathetic hormone response, then downregulation of pituitary sensitivity and pituitary exhaustion shown by lower circulating hormone concentrations
detraining
reduction in performance and loss of physiological adaptions due to no training or reduction in frequency, volume, or intensity
affect of 14 days detraining on strength
little to none
affect of 14 days detraining on muscle fiber type
little to none
how long detraining until fiber type is affected
8weeks
affect of 14 days detraining on muscle CSA
fast twitch - noticeable atrophy
slow twitch - little to none
cause of strength reduction in 8-12 weeks detraining
first neural mechanisms, then atrophy
