final Flashcards
acute fatigue
a decrease in maximal force or power production in response to contractile activity
mechanism of fatigue
- dehydration
- low glycogen
- metabolic molecules
- poor sleep
- stress
high intensity exercise
a maximal bout of activity which lasts for less than a second as long as 1-2 minutes and in which the majority of energy from anaerobic process
anaerobic processes
pcr and glycolysis
PCr resynthesis of ATP depends on
creatine levels
type 1 fibers
uses mitochondria
some glycolysis and pcr
fuel used when recruited - fat
glycogen depletion rate for type 1
slow - dont have a lot of glycolysis
type 2a machines present
both mito and glycolysis
-some pcr
type 2b machine present
pcr and glycolysis
some mito
fuel used - pcr and glucose
glycogen depletion rate type 2bs
very fast
if glycolysis cant run then we use ___ for fuel
fat, mito
triad of atp demand
- membrane - ca transport, Na - K pump
- SR - ca pump
- sarcomere - myosin atpase
excess phosphate inhibits
cross bridge cycling by reducing Ca sensitivity
and enters SR and binds to CA so that it cant leave to initiate cross. bridge cycling
Pi comes from releasing energy from ATP and if it doesnt re-synthesize fast enough it builds up
under high intensity conditions
the demand for ATP exceeds supply of atp
less sarcoplasmic CA leads to
less cross bridge cycling - calcium cant leave
breakdown of glycogen is inhibited
ca appearance stimulates glycogenolysis
low ph =
high amount of H
high ph =
low amount of H
LDH converts
pyruvate to lactate
when lactate is produced
Hs accumulate
largest producer of hydrogen
when ATPase releases energy from atp
lower ph inhibits
bioenergetic enzymes
intensity affects ___ the most
ROS
exercise increases
increase NO production
increase superoxide production
endurance exercise
prolonged steady state exercise performed for durations between four minutes and four hours, usually at the highest power output for the duration
complete oxidation of glucose
glycolysis
pdh
krebs
etc
oxidation of fatty acids
beta oxidation
krebs
etc
if atp is re-synthesized well then
pi doesnt accumulate
ca flow is uninterrupted
ROS doesnt accumulate
lactate and Atpase activity stays lower then H dont accumulate
increase dietary CHO decrease
glycogen use
glucose and fructose spare
glycogen the most
high intensity exercise increases
ADP and AMP
ROS
NAD
CA
increase in triggers lead to
mitochondrial biogenesis
angiogenesis
cho oxidation enzymes
to increase anaerobic capacity
need to increase PCR
- eating more creatine or supplementing
sarcolemma
muscle cell fiber membrane surrounds myofibril
t-tublules
carry action potential deep into muscle fiber
triad junction
t tubule
glycogen
glycolysis
myofibrils
functional contractile unit of skeletal muscle
sarcomeres
basic contractile element of skeletal muscle
actin
thin myofilaments
contains myosin binding sites
3 proteins make up thin filaments
actin
troponin
tropomyosin
troponin
binds to calcium released from SR
moves tropomyosin exposing myosin binding sites
tropomyosin
covers myosin binding sites on actin and enables muscles to relax when no sarcoplasmic CA
myosin
thick filament
heads contain actin binding sites
use ATP use to ratchet and has ATPase enzyme
myosin is stabilized by
titin
muscle shortens by
z disc getting closer (overlaps)
neuromuscular junction
site of communication between neuron and muscle
-consists of synapse between a motor neuron and muscle fiber
excitation contraction coupling
- action potential starts in brain and moves along spinal cord
- ap travels along alpha motor neuron towards NMJ
- ap arrives at nmj and causes release of acetylcholine
- ACH crosses synapses and bind s to ach receptors on plasmalemma
- ap travels down sarcolemma and into t-tubules
- ap inside t-tubule, triggers CA release from sarcoplasmic reticulum
- released ca enables myosin contraction
- ca binds to troponin and causes tropomyosin to uncover binding spots
crossbridge cycling
- myosin heads are energized but muscle is long
- cross bridge forms upon binding site uncovering
- myosin head ratchets using the energy
- myosin head binds new atp causing releasing Actin
- myosin atpase breaks atp down energizing myosin head
- if ca is still present then myosin head binds to another actin site further down to increase shortening
relaxed state
no sarcoplasm Ca stored in this state
tropomyosin is covering myosin binding sites
contracted state
ap caused SR to release CA into the sarcoplasm
Ca binds to troponin which causes tropomyosin to expose myosin binding sites on actin
type 1 fibers slow twitch
resistant to fatigue, slower ATPase, less developed Sr
- all the less
type 2 fast twitch glycolytic
fewer mito
faster atp generation
faster ATP
higher PCr
more developed SR
power athletes
atp is used for
myosin energizing
Na-K pumps
Ca pumps in SR and cell membrane
stored atp is high at ___ and low during ___
rest and high intensity work
Atp- PCr
very fast
no O2
substrate level synthesis of atp
uses creatine
most active during high intensity
substrate for gluconeogenesis
glycerol
AA
pyruvate or lactate
glycolysis reducing equivalents
NADH
ETC
PDH - linker between glycolysis and krebs
converts pyruvate to Acetylcoa
krebs produced REs to ETC
NADH
FADH2
OIL RIG
oxidation is losing
reduction is gaining
AMP increases
atp is decrease
during exercise
NAD increases
during exercise
intensity of exercise doesnt affect
appearance ofcalcium
hormones influenced by intensity
NAD, NADH, FADH, AMP
CHO rda
130 g
protein rda
0.8 g/kg bw
hypocalcemia
low calcium in the blood causes parathyroid to stimulate the parathyroid hormone which rips calcium from the blood and activates kidneys to use vitamin D
oxalates bind to
calcium and decrease its bioavailablity
phytates
bind to Fe
divalent cations
Fe, Mg, Ca, Cu, Zn
animal iron gets absorbed into
mucosa cells
plant iron gets absorbed
needs to be converted first before absorbed
fiber rda
14 grams per 1,000 kcals
sodium rda
1,500-2,300