Nutr 484 actual exam 1

Exercise

a planned structure of repetitive physical activity

Physiology

The study of processes and functions of living organisms

Together

The study of how and why the body responds to exercise

\-effective and efficient exercising

\-results body comp

\-minimize risk of injury

Health components of physical fitness

Cardio respiratory endurance

Body comp

Muscular strength

Muscular endurance

Flexibility

Skill components

Agility

Coordination

Balance

Power

Reaction time

Speed

Types of exercise

Aerobic and anaerobic

Aerobic

Endurance exercise such as cardio running cycling swimming etc

Anaerobic exercise

Springing resistance training (concentric vs eccentric) plyometric training

SAID principle

Specific

Adaptations to

Imposed

Demands

Basically adapt to how you train

How much exercise ?

150 minutes per week of moderate intensity

Or

75 minutes per week of vigorous intensity

Health benefits

Children and adults

\-increased muscular fitness

\-improved bone health

\-favorable changes in body comp

\-improved mood and mental health

Adults

\-reduced risk of premature death

\-Reduced risk of CVD risk factors and diseases

\-enhanced weight management

\-Reduced risk of cancer

Prescription of exercise

FITT-VP

Frequency

Intensity

Time

Type

Volume

Progression

Smooth muscle

Non striated

Autononomic nervous system

\-parasympathetic branch

Cardiac muscle

Striated

Autonomic nervous system

\-parasympathetic brand -inhibits

\-sympathetic branch - excites

Skeletal muscle

Striated

Somatic nervous system

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Epimysium

Outer layer

Peri my sim

Middle layer of connective tissue surrounding the vascular

Endomysium

Inner most layer surrounding the individuals muscle fibers

Myofibril

Myosin filament - thick and dark

Actin filament - thin and light

Sarcomere

Functional unit of a muscle fiber

Z line

Beginning and of the sarcomerer

One z line to the next

M line

Through the middle of myosin filament

H zone

The region between two different actins

A band

Runs the length of the myosin filament

Gives striated effect

I band

Region from one myosin filament to the next

Muscle contracting

Z lines come together

Z I H all shrink

Length of actin and myosin doesn’t change just slides

Sliding filament theory

Action potential starts in pre central gurus (motor cortex)

Through pyramidal tracts

Through ventral horn

At neuromuscular junction

* Releases acetylcholine


* binds to the receptor which initiated action potential
* ACHE into the synaptic cleft , degrades the ACH and reopens the receptors for next stimulus
* Calcium into sarcoplasm
* Calcium binds to troponin (on actin covered by troop-myosin)
* Contract is going to occur

Synapses with lower motor neuron

* 85% cross over
* ADP and P on myosin head cause swivel and contraction process
* Tropnin and tropomyosin complex shift back if no more action potential, muscles relax

Type 1 Slow twitch oxidative (SO)

Slow contraction

Weak force production

Fatigue resistant

Type 2A fast twitch oxidative glycolysis (FOG)

Type 2X Fast twitch (FG)

Factors affecting force production

Size of muscle fibers

Number of motor units

Type of motor unit

Rate coding

Speed of muscle contraction

Angle of pull

Initial muscle length

Sally Never Touched Randys Spoon and Igloos

All or nothing principle

Must hit threshold for response

Once threshold is hit it is a FULL response

Fatigue

During prolonged exercise when physical performance starts to decline

Central fatigue

Proximal to the neuromuscular junction

Insufficient binding of ACH

Peripheral fatigue

Distal to the neuromuscular junction

In the muscle itself

Accumulation of metabolic byproducts

* Hydrogen
* Inorganic phosphate

Decreases pH and ability to produce force

Accumulation hypothesis

30 seconds to three Minutes

Build up of metabolic byproducts

Lactate is not that bad

\-Does accumulate, but does not cause this

Hydrogen lower the pH

\-When it gets to 6.9 inhibits glycolysis

How to help

\-Bicarbonate loading

— reduce acidity in cellular environment

— favors diffusion of lactate

Depletion hypothesis

Prolonged exercise

No fuel source to produce ATP

\-phosphagen

\-glycogen (2000 stored)

How to help

\-Carbohydrate loading 70% diet

— go to increase muscle glycogen stores before competition

In combination with tapering

Blood

55% plasma

\-Mainly water with a little protein

Buffy coat

\-White blood cells

\-Platelets

Red blood cells erythrocytes 45%

\-hemoglobin, carrying oxygen

\-clotting and healing factors

Cardiac output

The amount of blood pumped by the heart per minute

\-At rest 5000 mL

\-during exercise 25,000 mL

\-Heart rate and stroke volume affect

\-HR x SV

Sinoatrial node (SA)

Pacemaker of the heart

Conduction starts in the snowed

60-100 beats per minute

P-wave

Contraction or depolarization of the atria

QRS complex

Ventricular depolarization contraction of the ventricles

T-wave

Ventricle repolarization back to resting state

First sound lub

Closing of the valves

Systolic

Second sound dub

Opening of the valves

Diastolic

Blood pressure

Systolic top number contraction of the ventricles, 120

Diastolic bottom number, relaxation of the ventricles to allow blood to refill 80

End, diastolic volume-the amount of blood left in the ventricles after contractions

End systolic volume-amount of blood left in the ventricles before contractions

Stroke, volume

Amount of blood per contraction of the heart

End diastolic-and systolic usually 50 to 60%

Preload-stretching of the walls of the heart

Greater stretching equals greater contractility

More blood left in the heart more blood expelled

Heart rate

Increases with exercise

Even Krisa is a little before beginning an exercise

Cardiovascular drift

Prolonged exercise at a low threshold

Increases in heart rate without changing in work rate

Stroke, volume

Decreases, so cardiac output can stay the same

To offset the heart rate increase

Increases to 40 to 60% max effort

Cardiac output

Stays the same

Only way to increase cardiac output is increase heart rate

Excess post exercise oxygen consumption (oxygen debt)

You’re in recovery and O2 remains elevated

Needed to replenish the stores that you used

Temperature regulation

Helps clear waste products

Aerobic threshold

Heart rate at about 150

Energy metabolism becomes mainly anaerobic

Anaerobic threshold

This is the ability to remove lactate from the area

Lactate threshold

Same point of anaerobic threshold

Accumulation exceeds removal

Ventilatory threshold

Idk but breathing

Onset blood lactate accumulation(OBLA)

Specific point of four mmol of blood

Oxygen, hemoglobin, disassociation curve

98% of O2 bound hemoglobin

2% plasma

Bohr effect -rightward shift in curve

\-Get oxygen to working muscles more efficiently

Normal to leftward shift is rare

Steady state, VO2

Plateau of O2, during exercise at two minutes below threshold

02 deficit

Slow component VO2

Two minutes above threshold, VO2 never steady states

Continuous increase after two minutes above

Drift VO2

Continuous increase at below threshold

Max VO2

The ability to consume transport and utilize oxygen

VO2

Q xA-V VO2 diff

\-flicks equation

\-Ficks law-rate of diffusion is proportional to surface area of a difference in partial pressure of gases (directly related)

\-Inversely related to the thickness of the barrier of the wall

\-Q equals cardiac output

\-Difference in oxygen Contant, an arterial and venous blood

Absolute VO2

L/min

Relative VO2

Ml/kg/min

Anytime kilograms is present it is relative to their body weight

Relative = absolute x 1000 / BW (in kg)

Girls 40-45

Boys 45-50

Factors affecting vo2 max

Mode of exercise

\-bike or treadmill

\-higher vo2 on treadmill compared to bike

—more muscle being used

Genetics

\-proportional of slow to fast twitch muscle fibers

Training

\-25%

Gender

\-women’s vo2 max is 15-32% lower

Body size and composition

\-lower % body fat - higher vo2

Age

\-peak at about 25-30 years

\-35 begins decline

Nervous system

Sensations

Movement

Proprioreception

\-where body is in space

Posture

Balance

Involuntary activities of living

Neuron

Starts at dendrite through axon to the nerve ending

Divisions

Anatomical

Functional

Central division

Brain and spinal cord

Peripheral

Any other nerves outside of the brain and spinal cord

Innervates muscles and glands

Parasympathetic

Slows

Inactivity

Rest and digest

Sympathetic

Excite

Fight or flight

Increase heart rate s

Somatic

Afferent neurons - sensory

Efferent neurons -motor

Proprioception vestibular receptors

In semicircular canals

Endolymoh

Disturbs the crista through 8th cranial nerve

Rotational information

* acceleration
* Deceleration
* Twisting

Otoliths
* Linear accelerations
* Where we are in space

Kinesthetic receptors

Movement and position of specific body parts in space re

Reflexes

Involuntary movements to a sensory stimuli s

Spinal reflex

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Minimum 2 neurons

Myostatic (stretch) reflex

2 neurons

Flexion reflex

3 neurons

Reciprocal inhibition

Idk

Crossed extensor reflex

Activation of contra lateral

Muscle spindle directly on the belly parallel to extra frusta fibers

Respons to stretch

Golgi tendon not parallel just lies in a series

\

Allows to be activated by passive stretching And active shortening of the muscle or tendon

Only a sensor neuron

Fundamental principles

Stimulating structural and functional adaptations to improve performance pr

Progressive overload

Achieving appropriate overload requires manipulating training

Anaerobic training

Resistance training

Plyometrics

Speed and agility

Interval training

Neural factors

Learning affect

Motor unit adaptations

\-increases requirements

\-increased firing rate

\-synchronization

Adaptations at the neuromuscular junction

\-increased surface area

\-dispersed irregular shaped synapses and length of nerve terminal

\-increased end plate perimeter length

Enhanced reflex responses

\-enhance magnitude and rate of force development

\-muscle spindles

Attenuated inhibition

\-golgi tendon organs

Hypertrophy

Increase in cell size

Skeletal muscle remodels sits internal architecture which could change external

Remodeling leads to increase in cross sectional area

Increase in size of muscle fibers

\-type 2> type 1

Increase in contractile protein

Increase in protein synthesis

Testosterone

Growth hormone

Insulin

Insulin like growth factor 1 s

Structural changes

Increased myofibril volume

\-more sarcomeres added

Increased angle of pennation

Reduced mitochondrial density

Satellite cells between basal laminate and sarcomeres

Muscle cells remodeling

Skeletal muscles represent dynamic tissues

Muscle fibers undergo regeneration and remodeling to alter their phenotypic profile

\-stimulation of myogenic stem cells situated under a muscle fibers basement memebrane

Specific training can transform muscle type

\-become more efficient

Satellite cells incorporate into existing muscle fibers

Signals determine myofilament proteins to be made

MTOR pathways

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Resistance training for protein synthesis

MAPK

Resistance training for transcription factors for hypertrophic gene expression

Absolute amount of hypertrophy represents the primary difference

\

Men experience greater absolute change in muscle size from their larger initial size

Enlargement as a percentage basis remains similar between sexes

Strength vs hypertrophy

Strength is proportion to CSA

S 1 to 6 reps technique improved

Neural

\-Golgi tendon bodies

\-Recruitment patterns

Training specific

H 6 to 12 or 15 reps over 65%

Goal is to increase training volume

Must go to fatigue

Greater volume training

\-Requires less weight

\-No difference to strength if the volume is matched

Requires volitional fatigue

Connective tissue

Mechanical force is Alyssa adaptations proportional to intensity

Increase in

\-Collagen, fibers diameter

\-Covalent crosslines between fibers

\-Collagen fibers

\-Density of collagen fibrils

Adapt, much more slowly than muscle

Bone density

Positive relationship between strength and bone mineral density

Strength and power activities have much more bone mass than endurance athletes

Linear relation exists between increase bone density, and total strength training program

Trabecular response, faster than cortical

Minimal essential strain approximately 1/10 fracture force

Long term aerobic training increases I heart mass and volume

Greater left ventricle end diastolic volume during rest and exercise E

Eccentric hypertrophy n

Elongated cardiomyocyte

Adding sarcomeres in series similar