metabolic pathways

muscles take chemical energy (ATP) and turn it into

mechanical work

flow of turning energy into movement

catabolism of fuel

ATP

force production

movement

ATP is the energy

currency

oxidative phosphorylation happens in the

in mitochondria

non-oxidative systems happen in the

cytoplasm

type 1 muscle fibers have high or low mitochondrial density

high - cannot be fatigued easily

when fibers have low capillary, low mitochondrial density, and low oxidative enzymes, what is likely to happen

fast fatiguability

normal concentration of ATP

8 mM

sinks in resting muscles

ion pumps

RNA and protein synthesis

fuel storage

transport substances

sinks in contracting muscles

all those in resting

myosin ATPase (contraction)

our body produces enough ATP so

we can maintain the 8 mM

how does the body create enough ATP

phosphocreatine

anaerobiv glycolysis

oxidative phosphorylation

phosphocreatine system

high power, low capacity

ten seconds work of energy at max effort

phosphocreatine occurs in the

cytoplasm

(non-oxidative)

anaerobic glycolysis

moderate power and capacity

associated with acidosis

glucose transporter recruited by

Exercise and insulin

exercise and insulin is used by diabetics becuase

it helps take the glucose out of the blood and puts it into the muscles

anaerobic glycolysis occurs in the

cytoplasm (non-oxidative

oxidative phosphorylation

low power, high capacity

oxidative phosphorylation takes how long to active

2-3 minutes

what is broken down in oxidative phosphorylation

lipids, proteins, carbohydrates

oxidative phosphorylation rate is measured by

oxygen consumption (VO2)

- proportional to workload

VO2 max represents

maximal aerobic capacity

oxidative phosphorylation occurs in

Mitochondria

Krebs cycle

strips electrons from the substrate group

electron transport chain

receives the electrons from the Krebs cycle and then transfers them to O2 to form water

what do we use when we jump out of the way of a bike

phosphocreatine

what do we used to climb a mountain

oxidative phosphorylation

what do we use to run a half a block to catch a bus

anaerobic glycolysis

glucose as a substrate

more rapid than others

limited capacity (500)

How much ATP is produced per molecule of glucose

36 ATP

lipids as substates

slower than glucose pathways but huge capacity (100,000)

free fatty acids go into

beta oxidation

glycerol goes through

glycolysis, then goes through the Kreb cycle

protein as a substrate

moderate capacity (24,000)

are proteins commonly used for energy/ATP

no

in the beginning of exercise we use

anaerobic cycles (phophocreatine and anaerobic glycolysis)

as time goes on while exercising we transition into using

aerobic cycles such as oxidative phosphorylation

as intensity increases

greater reliance on carbohydrates

as duration increases,

greater reliance on lipids

with high intensity, short duration activities (anaerobic)

increase in anaerobic substrate

increase quantity and activity of key glycolytic enzymes

with moderate intensity and long duration activities (aerobic)

increase in mitochondrial density

increase in oxidation of fats at rest

increase ability to oxidize carbohydrates at max exercise

cardiovascular changes with aerobic training

increase left ventricular volume = increase stroke volume

decrease HR at rest

increase peripheral vasodilation capacity

ventilatory changes with aerobic training

increase tidal volume and decrease respiratory rate

increase time for oxygen diffusion into blood

decrease energy cost of breathing

as bed rest duration extends, what happens to VO2 max

VO2 max decreases

as best rest duration extends, what happens to HR

HR increases

as best rest duration extends, what happens to stroke volume

stroke volume decreases

True or False: at rest, we derive the bulk of our energy though oxidative phosphorylation powered by the breakdown of lipids

True

True or False: with exercise training, our ability to re-generate ATP through the breakdown of lipids improves

true