Energy Ependiture- Exam 2

Direct calorimetry

Thermochamber, pipes circulating water, know the amount of water going in, measures the temp. of water coming out, measuring products.

40% of substrate energy

ATP

60% of substrate energy

Heat

Indirect calorimetry

measuring the substrates. Estimates total body energy expenditure based on O2 used and CO2 produced.

1L O2=

5 kcals

RER

ratio between rates of CO2 production, O2 usage. VCO2/VO2. This ratio helps us determine which fuels are being utilized. When you have a lot of carbon you need oxygen to attach to it. Fats have a lot more carbon so oxygen is needed to metabolize.

RER for 1 molecule glucose

1.0

RER for 1 molecule parmitic acid

0.70

Outside of the 0.7-1.0 range

Dont know much of what is going on, so other tests needed.

Isotope method

special water that contains heavy oxygen and heavy hydrogen

Pro of isotopic method

Not being watched, living in a free-living environment

If someone is really active what should be the result be of the isotope test

low oxygen levels because the oxygen is leaving the body as carbon dioxide

When RER is closer to 0.7

mostly fats

As the RER climbs from 0.7

mostly carbs

If RER is around 0.85

carbs and fat split 50/50

BMR

energy needed to stay alive, bare minimum amount of energy taken under strict circumstances. In supine position, thermoneutral environment, 8 hrs of sleep, and 12 hours fasting.

Tallest, skinny individual

higher BMR, more lean body tissue even though he weighs the same as the other individuals

RMR

More user-friendly but less accurate because the strict conditions are not there

TDEE

RMR + energy from PA + energy to process food

Biggest piece of TDEE

resting metabolis

Most variable piece of TDEE

Physical acitvity

VO2 max

Measures max amount of energy you can make aerobically, not anaerobically

How much can someone improve VO2 max

20%

Plateau of VO2 max

Once an athlete has impaired its VO2 by 20% a lot of physiology has changed so once it reaches that point it doesnt increase. There are limitations to your physiological changes, and genetic limits.

Absolute VO2 max

Basicmeasure, doesnt account for BW. L/min. Normaliing for non-weight bearing activities.

Relative VO2 max

Compares energy consumed and body weight. L/kg/min. Normalized for weight-bearing activities.

Individual VO2 max is 4.0 what is the kcals burned?

20 kcals

NO activity is 100%

aerobic or anaeorbic

At the start of any exercise yiu will have a greater

oxygen demand than what yoir aerobic energy system can produce

EPOC

greater energy production (O2 consumed) post exercise than your body actually needs. Return your body to homeostasis.

There is a gap in the beginning of exercise between

the requirement of O2 and energy made by aerobic metabolism

O2 deficit is

energy from anerobic metabolism

It takes how long before aerobic metabolism meets the demands

5-10 minutes

If youre a poor athlete your EPOC is higher or lower?

higher

How does EPOC work?

Post-exercise energy levels stay high for quite some time, so oxygen is going to be used to make energy, which allows your body to return to homeostasis.

Lactate

does not cause fatigue

When you metabolize glucose anaerobically

you get lactate which is a marker of glycolysis

As speed increases lactate increases or decreases?

increases

Before you start using lactate threshold you were using mainly aerobic metabolism

way to guage how efficient your aerobic metabolism. Longer it can stay aerobic the “happier” it is

Little lactate

Not going through glycolysis (anerobic metabolism)

lots of lactate

definitely going through glycolysis (aneraobic metabolism)

Critical power

tells us what intensities we can handle aerobically

Measure and compare athletes for a higher critical power especially in

endurance athletes

Successful endurance athletes predictors

High VO2 max, high lactate threshold, high economy og effect, high % of type I muscle fibers

More calorically involved

more expensive it will be

Two definitions of fatigue

Decrease in muscular force production or decrease in the will to continue to exercise

Rarely do we ever

completely fatigue

Goal of fatigue is to figure out if something is happening

mentally or physically

People to fatigue

high intesnity and type II muscle fibers

Peripheral fatigue

put yourself in a PA, start feeling weak

Central fatigue

Voice in your head that says stop

When you run out of creatine phosphate

Cant produce same rate of ATP and power production drops

Primary muscle group

will fail first ex. running, calves (the agonist) will fatigue first

Conservation of glycogen

imperative for exercise

With training individuals develop adaptation to allow for less dependence on

CHO

Glucose produces

acid and heat

Can only burn fat aerobically

temp affects this

What two factors can cause fatigue

heat and acid

WHen there is a lot of acid in the muscle what happens to pH

it goes down

Neural transmission

The motor nerve constantly shocks that muscle, calcium in the SR will be leaked at and is supposed to go to the sliding filaments. As you keep increasing calcium, some of it will end up in the mitochondria and that destroys the chemical gradient for the ETC.

Correlation between

central fatigue and heat, when one goes up so does the other

Central governor theory

inside the temporal lobe that once we hit that threshold, it will begin thoughts and feelings of fatigue to stop exercise. Mechanism to stop damage in body like organs.

People who have experiences trauma to their temporal lobe

best long endurance athlete because they have no central governor. Causes negative effects on body/health.

Nociceptors

in myotendinous junctions not in muscle bellies

Important for soreness

Dont stretch muscle that is sore

Best predictor of DOMS

training level

Insaids can

blunt inflammatory process of muscles