KIN 210- Exam 1 (msu)

2 fathers of exercise physiology

AV Hill, DB Dill

first exercise physiology lab in US

Harvard fatigue lab- 1927

focus of Harvard fatigue lab

Douglas bag

ability of the body to adjust to the demands of stresses and physical effort

physical fitness

ability of a single muscle or muscle group to exert force against a resistance

muscular strength (one time)

ability of a given muscle to sustain a given level of force, or contract and relax repeatedly at a given resistance

muscular endurance (over time)

ability to produce energy through increasing delivery of oxygen to working muscles

cardiorespiratory endurance

ability of a joint to move through its full range of motion (ROM)

flexibility

quantification of different components of body tissue, fat mass vs. non fat mass

body composition

ability to integrate workings of the central nervous system with the physical components of fitness

psychomotor ability

population norms

referenced standards, from previous research that allow for reflection of achievement of current conditions

reliable means...

reproducible

valid means...

measures what test is supposed to measure

highly controlled environment, more sophisticated equipment, highly accurate

laboratory tests

less controlled, can be done in large groups, results based on simple things (#of reps, heart rate)

field tests

FITT principles

Frequency

Intensity

Time

Type

training volume

sum of total work performed during a single training session, training week, or phase

progressive overload

level of stress that was previously needed to cause adaptation, no longer suitable, intensity must be increased

reversibility

long interruptions in training can cause negative results and decline in performance

primary molecule in human movement

adenosine triphosphate (ATP)

proteins most responsible for the movement in skeletal muscles

myosin

protein that contains the myosin-binding site

action

this covers the myosin binding site when not activated

tropomyosin

protein that when bound to calcium, move tropomyosin out of the way to allow for myosin to bind to actin during contraction

troponin

what does the alpha motor neuron do?

sneds signal to muscle fibers (located in spinal cord)

motor unit

a single alpha motor neuron and all of the muscle fibers that it innervates

STEPS OF MUSCLE CONTRACTION

1. signal starts at alpha motor neuron and propagates down the axon

2. action potential reached motor end plate located on the myofibrils

3. at end of axon acetylcholine is released across the synaptic cleft and binds to receptors on sarcolemma

4. once enough ach binds, an action potential occurs causing the release of calcium into sarcoplasm of cell

5. calcium travels down the t-tubules and into sarcoplasm of cell

6. in sarcomere, ca2+ binds to troponin

7. causes troponin to change shape and move tropomyosin out of way, exposing myosin binding site

8. ATP is present and bound to myosin, myosin head and ready to bind to actin

9. one phosphate from ATP is released and the power stroke occurs, pulling two lines of actin closer together (muscle shortens)

10. ADP is then released from myosin head

11. a new ATP molecule binds to myosin loads the myosin head and steps 8-9 occur again

12. for relaxation to occur, calcium must be removed from sarcoplasmic reticulum via a pump which also requires tap

skeletal muscle types

type 1 (slow twitch)- slow oxidative

type 2a (fast twitch)- fast oxidative/ glycolytic

type 2x (fast twitch)- fast glycolytic

type 1 color

black

type 2a color

white

type 2x color

gray

what are substrates

fuel sources from which we make energy (ATP)

what are bioenergetics

cellular processes by which substrates are converted into energy

metabolism

chemical reactions in body

calories

a measurement of heat released following a chemical reaction

1000 calories=

1kcal= 1 Calorie

basal metabolic rate

# of calories required for life-sustaining function only (heart function, digesting food, breathing, regulating core temp)

resting metabolic rate

Calories required at complete rest while accounting for low-effort activities and life-sustaining functions

which fiber type predominates in endurance athletes

type 1

which fiber type predominates in sprinters/ power athletes

type 2

2 primary types of contraction

static

dynamic

static contractions

muscle produces force but does not change length

dynamic contractions + what are two subtypes

muscle produces force and change length, subtypes are concentric and eccentric

concentric dynamic contractions

muscle shortens while producing force, most familiar type, sarcomere shortens

eccentric dynamic contractions

muscle lengthens while producing force, sarcomere lengthens, ex. is lowering heavy weight

3 main substrates used in energy production

carbohydrates, fats, proteins

carbs

4kcal of energy per 1g carb

all carbs converted to glucose

glycogen converted back to glucose when needed to make more atp

fats

9kcal of energy per 1g of fat

efficient storage

yields high net ATP but slow atp production

proteins

4kcal of energy per 1g of protein

energy substrate during starvation (converted intro glucose)

anabolic reaction

biosynthetic processes that build complex molecules from simpler ones, requires an input of energy to synthesize larger molecules

functions: growth , repair, maintenance of tissues

examples: protein synthesis, glycogenesis

catabolic reaction

reactions that involve the breakdown of complex molecules intro simpler, releasing energy in the process

functions: degradation of substances to release energy

examples: glycoside, lipolysis

phosphocreatine

substance stored in muscles that when broken down can donate a phosphate group to add to make atp for energy production

glycolytic system

metabolic pathway that is used by cells to oxidize glucose to generate atp, and intermediates for use in other metabolic processes

atp produced: 2-3 mole atp for every 1 mol of glucose/ glycogen

duration: 15s- 2min

the atp-pcr system

anaerobic metabolism

atp produced= 1 mol atp/ 1 mole of per

duration: 3-15 seconds

oxidative system

final set of pathways by which the body breaks down substrates, with the aid of oxygen to generate energy

takes place in mitochondria

krebs cycle

processes that further breaks down pyruvate to acetyl coa and produces energy from series of reactions

atp produced: 2 atp produced for every 1 molecule of glucose

electron transport chain

final step of glucose metabolism where electrons are passed through causing a release of energy

atop produced= about 34 atp for every 1 molecule of glucose

duration: 90 minutes

measuring energy expenditure via heat production is called

direct Calorimetry

analyzing the volume and composition of inhaled and exhaled gases

indirect Calorimetry

what makes up most of atmosphere

nitrogen (78%)

RER

respiratory exchange ratio

rate of energy used by the body

metabolic rate

- based on whole body o2 consumption snd corresponding caloric equivalent

absolute VO2 max

- expressed in L O2/min

- easy standard units

- suitable for non weight bearing activities

relative VO2 max

- expressed in mL O2/kg/min

- more accurate comparison for different body sizes