Midterm 1 Content Flashcards

Question

Lecture 1: What is the difference in the Sarcoplasm Reticulum’s of Type I vs Type II fibres?

Answer 1

Type II fibres have a more highly developed SR & the calcium release is faster & Vo is 3-5times faster

Answer 2

Type I motor units have smaller neurons with <300 fibres & type II motor units have larger neurons with >300 fibres - more units in type II, meaning more connections to the brain

Answer 3

Each person has a unique ratio that is mostly based on genetics - arm & leg ratios are similar in one person - typically more type I in endurance athletes & more type II in power athletes

Answer 4

The Soleus is type I in everyone

Answer 5

The possess high aerobic endurance & maintain prolonged exercise - require oxygen for ATP production - recruited for low-intensity aerobic exercise & DPA - ATP efficiently produced from fat & carbs

Answer 6

In general, they fatigue quickly as poor aerobic endurance & produce ATP anaerobically - Type IIa: produce more force & fatigue slower than I - Type IIx: seldom used for everyday activities

Answer 7

IIa - used for short, intense endurance (1,600m run) IIx - used for short, explosive sprints (100m)

Answer 8

1.) Genetics - determine which motor neurons innervate fibres & differentiate based on neuron 2.) Training - differentiate endurance, strength, & detraining. Training can induce small fibre type changes (10%)

Answer 9

Aging causes a loss of type II motor units as they begin behaving like type I fibres

Answer 10

A method used for altering force production - recruitment order = Type I, Type IIa, Type IIx

Answer 11

- less force production = fewer/smaller motor units - more force production = more/larger motor units - type I units are smaller than type II

Answer 12

1.) Static (isometric) 2.) Dynamic

Answer 13

Isometric contraction where muscle produces force but doesn’t change length - joint angle doesn’t change & myosin cross-bridges form & recycle with no sliding

Answer 14

Muscle produces force & changes length - joint movement is produced. Muscle lengthens/shortens

Answer 15

1.) Concentric (most common) - muscle shortens as sarcomere shortens & filaments slide towards eachother 2.) Eccentric - muscle lengthens as cross-bridges form but sarcomere lengthens (eg; lowering heavy weight)

Answer 16

Fuel sources we make energy from (eg; adenosine triphosphate ATP) Macronutrients absorbed from the diet - carbs, proteins, & fat (lipids)

Answer 17

The process that converts substrates into energy - a cellular-level process

Answer 18

Chemical reactions that occur in the body

Answer 19

Calculated from heat production - calculated in calories — 1cal = heat energy req’d to raise 1g of water from 14.5 degrees to 15.5

Answer 20

1,000 cal = 1 kcal = 1 Calorie (dietary)

Answer 21

1.) Carbohydrates 2.) Fat 3.) Protein - all contain carbon, hydrogen, oxygen, &/or nitrogen

Answer 22

Short = more carbohydrate Long = carbohydrate & fat

Answer 23

All carbs are converted to glucose & yield about 4.1kcal/g

Answer 24

~2,500kcal

Answer 25

Extra glucose is stored as glycogen in the liver & muscles - glycogen converted back to glucose when needed to make more ATP

Answer 26

Fat yields almost double the amount of energy as carbs as it makes 9.4kcal/g - yields high net ATP but slow ATP production

Answer 27

70,000+ kcal of fat stored in the body

Answer 28

Broken down into free fatty acids (FFAs) & glycerol **only FFAs are used to make ATP

Answer 29

Used for energy during starvation & yields 4.1kcal/g

Answer 30

Need to be broken down into individual amino acids & then into glucose in order to be used. - convert into FFAs through lipogenesis for energy storage and cellular energy substrate

Answer 31

Energy is released at a controlled rate based on availability of primary substrate

Answer 32

Explain how substrate availability affects metabolic rate - more substrate available = higher pathway activity - excess of given substrate = cells rely on that substrate more than others

Answer 33

Energy release rate is controlled by enzyme activity in the metabolic pathway - more enzymes = more ATP produced

Answer 34

They facilitate breakdown (catabolism) of substrates & catalyze individual reactions to produce more ATP - they can speed up or slow down reactions based on ATP requirements - they lower the activation energy for a chemical reaction - end with suffix “-ase”

Answer 35

Facilitates production of glucose when turned on or reduces rate of production when turned off - used in glycolysis

Answer 36

Can create a bottleneck effect at an early step - activity is influenced by negative feedback & slows overall reaction to prevent runaway reaction

Answer 37

ATP is stored in small amounts until needed & stored in phosphate bonds in muscle

Answer 38

ATP is broken down to release energy by using ATPase enzymes ATP + Water + ATPase —> ADP + Pi + energy *ADP is a lower-energy compound that is less useful

Answer 39

ATP is synthesized through phosphorylation & can occur in either absence or presence of Oxygen ADP + Pi + energy —> ATP

Answer 40

1.) ATP-PCr System ~ anaerobic metabolism 2.) Glycolytic System ~ anaerobic metabolism 3.) Oxidative System ~ aerobic metabolism

Answer 41

Anaerobic system (no oxygen) with substrate-level metabolism and also called the Phosphate Creatine system - ATP Yield = 1 ATP/1 PCr - Duration = 3-15s - Pathway is used to reassemble ATP because ATP stores are very limited

Answer 42

PCr = phosphocreatine & used for ATP recycling - PCr + creatine kinase —> Cr + Pi + energy - PCr energy cannot be used for cellular work but can be used to reassemble ATP - it replenishes ATP stores @ rest & recycles ATP during exercise until used up

Answer 43

PCr breakdown is cataloged by the CK enzyme (creatine kinase) - CK controls rate of ATP production based on negative feedback *low ATP & high ADP causes CK activity to increase * high ATP levels cause CK activity to decrease

Answer 44

An anaerobic system for ATP synthesis that does not require oxygen - ATP yield = 2-3 mol ATP/ 1 mol substrate - Duration = 15s - 2min - breaks down glucose via glycolysis

Answer 45

Uses glucose or glycogen as its substrate - costs 1 ATP for glucose & 0 ATP for glycogen - must convert to glucose-6-phosphate

Answer 46

Pathway starts with glucose-6-phosphate & ends with pyruvic acid - 10-12 enzymatic reactions total - all steps occur int eh cytoplasm - ATP Yield: 2 ATP for glucose & 3 for glycogen

Answer 47

1.) low ATP yield & inefficient use of substrate 2.) lack of O2 converts pyruvic acid to lactic acid 3.) lactic acid impairs glycolysis & muscle contraction as it impairs ability to produce ATP

Answer 48

1.) Allows muscles to contract when O2 is limited 2.) Permits shorter-term, high-intensity exercise than oxidative metabolism can sustain

Answer 49

Phosphofructokinase (PFK) is a rate-limiting enzyme that regulates ATP production. - lower ATP = higher PFK activity… higher ATP = lower PFK activity **PFK levels also regulated by products of Krebs cycle - Glycolysis = ~2mins max exercise… need another pathway for longer durations

Answer 50

Aerobic system that yields way more ATP than other systems & is less intense as ATP is produced slowly - ATP Yield is dependent on substrate… 32-33ATP/1g glucose & 100+ ATP/1 FFA - Duration = steady supply for hours - Location = mitochondria (not cytoplasm) - most complex system of the 3 bioenergetic systems

Answer 51

1.) Glycolysis 2.) Krebs Cycle 3.) Electron Transport Chain (ETC)

Answer 52

H+ & electrons are carried to the ETC via NADH & FADH2 molecules - H+ & electrons travel down the chain…. 1.) H+ combines with O2 & forms H2O 2.) Electrons & O2 help form ATP 3.) 2.5 ATP per NADH & 1.5 ATP per FADH2

Answer 53

Triglycerides (major fat energy source) are broken down into 1 glycerol & 3 FFAs through lipolysis (carried out by lipases) - Rate of FFAs entry into muscle is dependent on concentration gradient - Yields 3-4 times more ATP than glucose - slower than glucose oxidation

Answer 54

The process converting FFAs (fatty acids) to acetylene-CoA before entering Krebs Cycle - uses 2 ATP right away

Answer 55

# of steps depends on # of carbons on FFA (fatty acids) - 16-carbon FFA yields 8 acetyl-CoA compared to 1 glucose yielding 2 acetyl-CoA - fat oxidation required more O2 at beginning & yields far more ATP later

Answer 56

Acetyl-CoA enters Krebs cycle & follows same path as glucose oxidation - different fatty acids have different #’s of carbons meaning they… yield different #’s of acetyl-CoA molecules, & Yield different ATP

Answer 57

Protein rarely used as a substrate but can be converted to glucose & Acetyl-CoA - energy yield not easy to determine as nitrogen presence is unique & excretion requires ATP

Answer 58

Lactate is an important fuel during exercise & can be used by muscles in 3 ways… 1.) lactate produced in cytoplasm is taken up by mitochondria (of same muscle fibre) & oxidized 2.) lactate transported via MCP transporters to another cell & oxidized there (lactate shuttle) 3.) lactate recirculates back to liver & reconverted to pyruvate & then glucose through gluconeogenesis

Answer 59

All 3 systems interact for all activities as no single system contributes 100% but one system will often dominate - cooperation between systems increases during transition periods

Answer 60

**Cross-over point is the intersection of these 2, which is affected by exercise intensity & endurance training - at rest & exercise below 60% VO2max lipids are the primary substrate - at high intensity & above 75% VO2max carbohydrates are the primary substrate

Answer 61

Not all muscles have maximal oxidative capability’s but can be determined by… 1.) Enzyme activity 2.) Fibre type composition & endurance training 3.) O2 availability versus need

Answer 62

Not all muscles exhibit optimal activity of oxidative enzymes - representative enzymes include; succinate dehydrogenase & citrate synthase - levels differ in endurance-trained vs untrained individuals

Answer 63

The basic structural unit of nervous system also called a nerve & is an excitable tissue that sends nerve impulses down cellular membranes

Answer 64

1.) Cell body (soma) 2.) Dendrites 3.) Axon

Answer 65

Myelin speeds up propagation & axons with a larger diameter speed propagation as well

Answer 66

Myelin can be a fatty sheath around the axon & called Schwann cells or not continuous layers that are called nodes of Ranvier - saltitory conduction

Answer 67

Schwann cells = continuous fatty myelin sheath around the axon made of glial cells Nodes of Ranvier = non continuous myelination

Answer 68

The junction/gap between neuron’s that serves as a site of neuron-to-neuron communication *AP must jump across the synapse

Answer 69

Axon —> synapse —> dendrites Presynaptic cell —> synaptic cleft —> postsynaptic cell **signal changes form across synapse Electrical —> Chemical —> Electrical

Answer 70

AP can only move in one direction & axon terminals contain neurotransmitters that serve as chemical messengers - they carry electrical AP across synaptic cleft - bind to receptor on postsynaptic surface - stimulate GP’s in postsynaptic neuron

Answer 71

50+ are known - ACh & Noepinephrine (NE) govern exercise which increases acetylcholine (ACh)

Answer 72

Governs exercise & stimulates skeletal muscle contraction, & mediates parasympathetic nervous system effects

Answer 73

NE mediates sympathetic nervous system effects

Answer 74

Peroxisome Profilferator-activated receptor-y coactivator 1a

Answer 75

A molecule that is more available during exercise 1.) increases branching of the presynaptic terminal motor neuron 2.) increases the # of presynaptic vesicles containing acetylcholine 3.) increase the # of acetylcholine receptors on the cell membrane 4.) decreases the size of the motor end plate

Answer 76

1.) Excitatory Postsynaptic Potential (EPSP) 2.) Inhibitory Postsynaptic Potential (IPSP)

Answer 77

This is a depolarization, excitatory response that promotes Action Potentials - More EPSPs = more depolarization - if you reach threshold depolarization that AP occurs

Answer 78

This is a hyperpolarization, inhibitory response that prevents Action Potentials - multiple IPSPs = more hyperpolarizing

Answer 79

- Frontal lobe - Parietal lobe - Occipital lobe - Temporal lobe *basal ganglia

Answer 80

Frontal lobe = primary motor cortex - responsible for conscious control of muscle movement - pathway = pyramidal cells > Corticospinal tract > spinal cord

Answer 81

Parietal lobe

Answer 82

The cerebral white matter that include clusters of cell bodies deep in the cerebral cortex & initiate sustained or repetitive movements Eg; walking, running, posture, muscle tone, etc

Answer 83

1.) Thalamus 2.) Hypothalamus

Answer 84

Serves as a major sensory relay center that determines what we are consciously aware of

Answer 85

Maintains homeostasis & regulates internal environment using neuroendocrine control - eg; appetite, thirst, fluid balance, sleep, blood pressure, heart rate, breathing, temperature, etc. - controls systems typically under involuntary control

Answer 86

Controls rapid/complex movements & coordinates timing/sequence of the movements - compares movements with intentions & initiated corrections - accounts for body position & muscle status - receives input from primary motor cortex (frontal lobe) to help execute/refine movements

Answer 87

1.) Midbrain 2.) Pons 3.) Medulla Oblongata

Answer 88

To relay information between the brain & spinal cord

Answer 89

To coordinate skeletal muscle formation/tone & control cardiovascular/respirator functions

Answer 90

Where pain is modulated by opioid substances as b-endorphins are released here with exercise

Answer 91

Tract of nerve fibres that permit 2-way conduction of nerve impulses that is continuous with the medulla oblongata

Answer 92

1.) Ascending Afferent (sensory) fibres 2.) Descending Efferent (motor) fibres

Answer 93

PNS is connected to brain & spinal cord - 12 pairs of cranial nerves (connected to brain) - 31 pairs of spinal nerves (connected to spinal cord) *both types directly supply skeletal muscles

Answer 94

1.) Sensory (Afferent) division 2.) Motor (efferent) division

Answer 95

Transmits information from periphery to the brain & includes major families of sensory receptors

Answer 96

1.) Mechanoreceptors - physical forces 2.) Thermoreceptors - temperature 3.) Nociceptors - pain 4.) Photoreceptors - light 5.) Chemoreceptors - chemical stimuli (changes in o2 levels etc)

Answer 97

Receptors sensitive to joint angles & rate of angle change (degrees of flexion or extension) - they sense joint position & movement

Answer 98

* specialized intramural muscle fibres innervated by g-motor neurons Sensory fibres/nerve clusters sensitive to muscle length & rate of change - they sense muscle stretch and rate/amount of stretch

Answer 99

They are sensitive to tension in the tendons & sense strength of contractions

Answer 100

Transmit information from the brain to periphery & has 2 subdivisions: 1.) Autonomic - regulates visceral activity 2.) Somatic - stimulates skeletal muscle activity

Answer 101

Regulates visceral activity & controls involuntary internal functions - helps with exercise-related autonomic regulation such as heart rate, blood pressure, & lung functions

Answer 102

1.) Sympathetic Nervous System - fight or flight (prepares body for exercise) 2.) Parasympathetic Nervous System - rest & digest (state of conserving energy)

Answer 103

The fight or flight response in preparation for exercise… when stimulation increases… - heart rate & blood pressure increase - blood flow to muscles increase - airway diameter increases (bronchodilation) - metabolic rate, glucose levels, and FFA levels increase

Answer 104

The rest & digest activity that opposes sympathetic effects as trying to conserve energy for next sympathetic event - digestion & urination increases - heart rate decreases - diameter of vessels & airways decreases

Answer 105

The communication & interaction between sensory & motor systems

Answer 106

1.) Stimulus sensed by sensory receptor 2.) Sensory AP sent to sensory neurons in CNS 3.) CNS interprets sensory info & sends out response 4.) Motor AP sent out on alpha-motor neurons 5.) arrives at skeletal muscle & response occurs

Answer 107

As level of control moves from spinal cord to cerebral cortex, movement complexity increases

Answer 108

Motor reflex is an instant, preprogrammed response to stimulus & is identical each time - occurs before conscious awareness - impulse is integrated at lower, simple levels

Answer 109

It’s a chemical communication system that maintains homeostasis via hormones

Answer 110

endocrine system is slower to respond than the nervous system but is longer lasting

Answer 111

1.) controls substrate metabolism 2.) regulates fluid & electrolyte balance

Answer 112

Thyroid gland, adrenal glands, pancreas, & kidneys

Answer 113

Derived from cholesterol & are lipid soluble as they can diffuse through membranes - aldosterone is an important for fluid balance

Answer 114

1.) Adrenal Cortex - cortisol & aldosterone 2.) Ovaries - estrogen & progesterone 3.) Testes - testosterone 4.) Placenta - estrogen & progesterone

Answer 115

Non lipid-soluble hormones that are unable to cross membranes & include 2 types; Protein/Peptides & Amino-Acid Derived

Answer 116

The most common type of non-steroidal hormones that are secreted from the pancreas, hypothalamus, & pituitary glands

Answer 117

Includes the thyroidal hormones (T3 & T4) and the Adrenal Medulla Hormones including epinephrine & noepinephrine

Answer 118

Secreted in bursts (pulsatile) as plasma concentrations fluctuate over minutes/hours & days/weeks

Answer 119

Regulated by negative feedback as hormone release causes a change in the body - large downstream change reduces secretion - small downstream change increases secretion - eg; home thermostat

Answer 120

The decrease in # of receptors during high plasma concentration & causes desensitization for receiving hormones

Answer 121

The increase in # of receptors during high plasma concentration & causes sensitization for hormones

Answer 122

Use hormone-specific receptors to limit the scope of their effects & bind to correct receptors *if no receptors than there is no hormone effect

Answer 123

1.) hormone affects only tissues with specific receptors 2.) hormone exerts effects after binding with receptors - typical cells have 2,000-10,000 receptors

Answer 124

Inside the cell in the cytoplasm or nucleus -hormone-receptor complex enters nucleus & binds DNA to direct gene activation & regulate the synthesis of mRNA & proteins

Answer 125

Receptors on cell membranes go to second membrane systems to carry out hormone effects

Answer 126

Second messengers carry out & intensify the effects of hormones 1.) Cyclic Adenosine Monophosphate (cAMP) 2.) Cyclic Guanine Monophosphate (cGMP) 3.) Inositol Triphosphate (IP3) & Diacylglycerol (DAG)

Answer 127

Attached to the inferior hypothalamus of the brain

Answer 128

1.) Anterior (most important) 2.) Intermediate 3.) Posterior

Answer 129

Secretes hormones in response to hypothalamic hormone factors: - releasing & inhibiting factors - exercise increases secretion of all anterior pituitary hormones

Answer 130

Growth Hormone (GH) is a potent anabolic hormone that’s release is proportional to exercise intensity (increased GH release when increase in intensity) - helps build tissue & organs, promotes muscle growth (hypertrophy), & stimulates fat metabolism

Answer 131

Triiodothyronin (T3) & Thyroxine (T4)

Answer 132

T3 & T4 increase… - metabolic rates of all tissues - protein synthesis # & size of mitochondria - glucose uptake by cells - rate of glycolysis & gluconeogenesis - FFA mobilization

Answer 133

1.) The Anterior Pituitary releases thyrotropin (Thyroid-stimulating hormone/TSH) that travels to the thyroid gland and stimulates release of T3 & T4 2.) Exercise speeds up release of TSH - short exercise = T4 increases & long exercise = T4 constant & T3 decreases

Answer 134

Releases catecholamines (80% Epinephrine & 20% NE) that help with the fight or flight response - exercise increases which increases SNS & increases release of E & NE

Answer 135

1.) heart rate, contractile force, & blood pressure increase in the heart 2.) Glycolysis & FFAs increase 3.) Blood flow to skeletal muscle increases

Answer 136

Releases corticosteroids which include: - glucocorticoids - mineralocoticoids - gonadocorticoids

Answer 137

Cortisol is the major glucocorticoid & stimulates glucogenesis while increasing FFA mobilization & protein catabolism - acts as an anti-inflammatory & depresses anti-immune reactions

Answer 138

1.) Insulin - used to lower blood glucose levels 2.) Glucagon - used to raise blood glucose levels

Answer 139

Lowers blood glucose by countering hyperglycaemia and opposing glucagon - facilitates glucose transport into cells - enhances synthesis of glycogen, protein, & fat - inhibits (stops) gluconeogenesis

Answer 140

Glucagon raises blood glucose levels by countering hypoglycemia & opposes insulin - promotes glycogenolysis & gluconeogenesis

Answer 141

1.) Glucose must be available to tissues 2.) Adequate glucose during exercise requires glucose re;ease from liver & glucose uptake by muscles 3.) some hormones help increase circulating glucose such as; glucagon, epinephrine, noepinephrine, & cortisol

Answer 142

The process of turning glycogen into glucose

Answer 143

The process of turning FFAs & proteins into glucose

Answer 144

GH causes an increase in FFA mobilization which causes a decrease in cellular glucose uptake

Answer 145

T3 & T4 hormones cause an increase in glucose catabolism & fat metabolism

Answer 146

Exercise intensity & duration

Answer 147

- catecholamine release increases - glycogenolysis rate increases in liver & muscles - muscle glycogen is used before the liver glycogen

Answer 148

- more liver glycogen is sued - increase in muscle glucose uptake causes increase in liver glucose release - glycogen stores decrease causes glucagon ;evils to increase

Answer 149

Insulin concentrations decrease & cellular insulin sensitivity increases causing more glucose to be taken up into the cells & less insulin is used

Answer 150

CNS regulates carbohydrate metabolism through hormones (insulin) & nutrients (glucose, FFAs, & amino acids) - brain sensitive to glucose & helps control insulin release - Leptin & GLP-1 hormones are released by adipose tissue & act through the CNS to decrease glucose production *glucose is the only substrate for brain metabolism

Answer 151

FFA mobilization & fat metabolism is critical to endurance exercise as glycogen is depleted & fat energy is required, causing lipolysis acceleration - Triglycerides broken down into FFAs & glycerol

Answer 152

Tryglycerides broken down into FFAs & Glycerol - fat is stored as tryglycerides in adipose tissue - broken into FFAs & transported to muscles - rate of this breakdown is a possible determinant of the rate of cellular fat metabolism

Answer 153

Lipolysis is the breakdown of fat & is stimulated by: - decreased insulin levels - epinephrine & norepinephrine - cortisol - Growth Hormone *they stimulate lipolysis via lipase enzyme

Answer 154

1.) increases hydrostatic pressing & tissue osmotic pressure 2.) decreases plasma water content through sweating 3.) increases heart strain, which decreases blood pressure

Answer 155

1.) Posterior Pituitary Gland 2.) Adrenal Cortex 3.) Kidneys

Answer 156

Posterior pituitary secretes Antidiuretic hormone (ADH) & oxytocin which are produced in the hypothalamus & travel to posterior pituitary & secreted when brain signals from hypothalamus - Only ADH is involved with exercise to increase water reabsorption in kidneys & less water in urine (antidiuresis)

Answer 157

1.) decrease in plasma volume (hemoconcentration) causes increase in osmolality 2.) increases osmolality & stimulates osmoreceptors in hypothalamus *ADH is released & increases water retention by kidneys (minimizes water loss & severe dehydration)

Answer 158

They secrete mineralocorticoids, the main one is aldosterone which acts on kidneys & causes sodium retention from urine into the blood so water is reabsorbed to maintain osmolaty

Answer 159

Aldosterone released from the Adrenal Cortex causes… 1.) increases Na+ retention by kidneys 2.) increases Na+ retention to increase water retention via osmosis 3.) increases Na+ retention to increase K+ excretion

Answer 160

Decrease in plasma Na+ Decrease in blood volume & blood pressure Increase in Plasma K+

Answer 161

Kidneys are target tissues for ADH & they secret erythropoietin (EPO) & renin

Answer 162

EPO released in response to low blood O2 in the kidneys - simulates red blood cell production which is critical for adapting to training & altitude

Answer 163

Decreased blood volume & decreased blood pressure - sympathetic nervous system impulses

Answer 164

Process where renin converts angiotensinogen into angiotensin I & then ACE converts Angiotensin I into Angiotensin II which stimulates the release of Aldosterone

Answer 165

Constricts blood vessels to increase pressure causes kidneys to release aldosterone & brainstem to increase thirst to increase water intake

Answer 166

The measure of concentration of dissolved particles (proteins, ions, etc) in the body’s fluid compartments - normal value + ~300mOsm/kg

Answer 167

If compartments osmolality increases than water is drawn in but is compartment osmolality decreases than water is drawn out (osmosis)

Answer 168

Na+ retention causes increased osmolality which leads to increased water retention because where Na+ moves, water follows - Osmotic water movement minimizes loss of plasma volume & maintains blood pressure

Answer 169

The measurement of temperature change from heat produced during energy production/expenditure

Answer 170

40% of substrate energy turns into ATP 60% of substrate energy turns into heat

Answer 171

1.) Energy can be created or destroyed 2.) any chemical reaction in the body will release heat

Answer 172

Heat production increases with energy production - can be measured with calorimeter - water flows through walls & body temp increases the water temp

Answer 173

1.) Accurate over time & more precise 2.) Good for resting metabolic measurements

Answer 174

1.) expensive & slow (box is very pricey) 2.) heat added by exercise equipment (eg; treadmill creates friction heat) 3.) Measurement errors created by sweat 4.) Neither practical nor accurate for exercise

Answer 175

Way of measuring expiratory gases under certain conditions & estimates total body energy expenditure based on O2 used & CO2 produced - measures respiratory gas concentration

Answer 176

Is accurate for steady-state oxidative metabolism **older methods are accurate but slow & newer methods are faster but expensive

Answer 177

VO2 = volume of O2 consumed per minute (rate of O2 consumption) & units = L/min *volume of inspired O2 minus volume of expired O2 *Formula = (Vi x FiO2) - (Ve x FeO2)*

Answer 178

The volume of CO2 produced per minute (rate of CO2 produced) & units = L/min *VCO2 = volume expired CO2 minus Volume inspired CO2 *Formula = (Ve x FeCO2) - (Vi x FiCO2)

Answer 179

FiO2 = fraction of O2 in the air we inhale FiCO2 = fraction of CO2 in the air we inhale FeO2 = fraction of O2 expired into the air FeCO2 = fraction of CO2 expired into the air

Answer 180

Always 20.93% or 21%

Answer 181

Always 0.03%

Answer 182

The ratio between rates of CO2 production & O2 usage - RER = VCO2/VO2 - no units as it is a ratio

Answer 183

Depends on type of fuel being oxidized - more carbon atoms = more O2 needed

Answer 184

Predicts substrate usage & how much energy is required which is measured in Kcal/O2 efficiency RER = efficiency of energy substrate

Answer 185

Between 1.0 & 0.7 *use chart to see these ratios

Answer 186

1.) CO2 production may not = CO2 exhalation 2.) RER is inaccurate for protein oxidation 3.) RER near 1.0 may be inaccurate when lactate buildup increases CO2 exhalation 4.) Glucogenesis produces RER <0.70 5.) doesn’t work on someone malnourished

Answer 187

1.) Calculate VO2 2.) Calculate VCO2 3.) Calculate RER 4.) use RER to obtain kcal/LO2 (on chart) 5.) Use kcal/LO2 & VO2 to calculate EE

Answer 188

The rate of energy use by the body based on whole body O2 consumption & corresponding caloric equivalent *@ rest RER = 0.80 & O2 = 0.3L/min * @ rest metabolic rate = 2,000 kcal/day

Answer 189

BMR = rate of energy expendature @ rest - found when in supine position, thermoneutral environment, & after 8hrs of sleep & 12hrs fasting

Answer 190

BMR find the minimum energy required for living & can be affected by body surface area, age, stress, hormones, body temp, etc

Answer 191

Typically what we measure as rules are not as strict & is like BMR but easier (within 5-10% range) - stringent standardized conditions not required - 1,200 - 2,400 kcal/day - looks @ total daily metabolic activity

Answer 192

- metabolic rate increases with exercise intensity - slow component of O2 uptake kinetics (at higher outputs, VO2 increases as more Type II fibre recruitment occurs) - VO2 drift = upward drift at low power outputs possibly due to ventilators hormone changes (occurs when recruiting Type II fibres)

Answer 193

- metabolic rate increases with exercise intensity - slow component of O2 uptake kinetics (at higher outputs, VO2 increases as more Type II fibre recruitment occurs) - VO2 drift = upward drift at low power outputs possibly due to ventilators hormone changes (occurs when recruiting Type II fibres)

Answer 194

1.) decrements in muscular performance with continued effort, accompanied by sensations of tiredness 2.) inability of muscle(s) to maintain required power output to continue muscular work at given intensity

Answer 195

Fatigue is reversible by rest & isn’t necessarily catastrophic but is a continuum @ reduced rate

Answer 196

1.) inadequate energy delivery/metabolism 2.) accumulation of metabolic by-products 3.) failure of muscle contractile mechanism 4.) altered neural control of muscle contraction

Answer 197

PCr (phospho-creatine) is used for short-term, high-intensity effort & gets depleted more quickly than total ATP (Pacing helps defer depletion) *Pi accumulation may be potential cause

Answer 198

Glycogen depletion is correlated with fatigue as reserves are limited & get depleted quickly - fatigue related to total glycogen depletion but unrelated to rate of glycogen depletion

Answer 199

Glycogen is depleted more quickly with high intensity & depleted more quickly during first few minutes of exercise

Answer 200

Fibres recruited first/most often get depleted fastest - type I fibres depleted after moderate endurance exercise

Answer 201

- Type I fibres recruited first (for light/moderate intensity) - Type IIa fibres recruited next (for moderate/high intensity) - Type IIx fibres recruited last (for maximal intensity)

Answer 202

Activity-specific muscles are depleted faster as they’re recruited the earliest & for he longest time

Answer 203

When muscle glycogen isn’t enough for prolonged exercise, liver glycogen turns to glucose & enters blood stream - when muscle glycogen decreases, liver glycogenolysis increases

Answer 204

1.) Pi - from rapid breakdown of PCr to form ATP 2.) Heat - retained by body & core temp increases 3.) Lactic Acid - product of anaerobic glycolysis

Answer 205

Heat increases rate of carbohydrate utilization & speeds up glycogen depletion - high muscle temperature may impair muscle function

Answer 206

- longest time to exhaustion = 11degC - shortest time to exhaustion = 31degC - *muscle precooking prolongs exercise

Answer 207

Lactic acid converts to Lactate & H+ which causes decrease in muscle pH (causing acidosis)

Answer 208

pH <6.9 inhibits the glycolytic enzymes used for ATP synthesis pH = 6.4 prevents further glycogen breakdown

Answer 209

Fibre recruitment may be reduced due to… - stress of exhaustive exercise may be too much - someone may be unwilling to endure more pain - discomfort of fatigue is a warning sign to stop - elite athletes learn proper pacing to tolerate fatigue

Answer 210

Muscle soreness = accuse soreness during & immediately after exercise & felt anytime (delayed-onset 1-2 days later) - Results from exhaustive/high-intensity exercise (especially when performed for the first time)

Answer 211

Felt during or immediately after strenuous/novel exercise caused by accumulation of metabolic by-products (H+) & disappears in minutes-hours

Answer 212

Tissue edema occurs due to plasma fluid in the interstitial place & causes acute muscle swelling

Answer 213

Delayed-onset muscle soreness

Answer 214

Delayed-onset muscle soreness that appears 1-2 days after exercise causes predominantly by eccentric contractions - stiffness to restrictive pain -eg; level-run pain < downhill-run pain (not caused by increase in blood lactate oncentrations)

Answer 215

Structural damage caused by DOMS is indicated by muscle enzymes in blood - enzyme concentrations in blood increase 2-10 times after heavy training - onset of DOMS parallels the onset of increased muscle enzymes in blood

Answer 216

Inflammation & DOMS are connected as white blood cells count increases with soreness and neutrophils are released due to damaged muscle cells

Answer 217

Increase muscle tension leads to structural damage to muscle/cells - membrane damage disturbs Ca2+ homeostasis & inhibits cellular respiration causing activation of enzymes that degrade Z-disks - circulating neutrophils increase as products of macrophage activity accumulate & stimulate pain - fluid & electrolytes shift to the area & create edema

Answer 218

DOMS reduce muscle force generation as there is a loss of strength due to 3 factors… 1.) physical disruption of muscle 2.) failure in excitation-contraction coupling 3.) loss of contractile protein

Answer 219

1.) minimize eccentric work early in training 2.) start with low intensity & increase slowly 3.) start with higher-intensity (exhaustive training) - soreness starts bad but much less later on

Answer 220

EAMC = exercise-associated muscle cramps that are localized to an overworked muscle - due to lack of conditioning, improper training, & depletion of muscle energy stores - treated with stretching & reduced by changing excitatory properties of neuron

Answer 221

Associated with large sweat & electrolyte losses (sodium & chloride) *coupled with dehydration - treated with high sodium solution, ice, & massage

Answer 222

1.) Delivers O2 & nutrients 2.) removes CO2 & wastes 3.) transports hormones & other molecules 4.) Supports temperature balance & fluid regulation 5.) maintains acid-base balance 6.) regulates immune function

Answer 223

1.) Heart (pump) 2.) Blood Vessels (channels/tubes) 3.) Blood (fluid medium)

Answer 224

Pulmonary circulation ( deoxygenated blood from body & pumped to lungs) - superior & inferior vena cava to RA to tricuspid valve to RV to pulmonary valve to pulmonary arteries to lungs

Answer 225

Systemic Circulation (pumps oxygenated blood from the lungs to the body) - lungs to pulmonary veins to LA to mitral valve to LV to aortic valve to aorta

Answer 226

Myocardium is heart muscle & left ventricular has most myocardium beacause it must pump blood to entire body so its largest & has thickest walls

Answer 227

Connected by intercalated discs with desmosomes holding the cells together - gap junctions rapidly conduct action potentials

Answer 228

Skeletal muscle: large, long, unbranded, multinucleated cells with intermittent, voluntary contractions & Ca2+ released from SR Myocardial Cells: small, short, branched, single nucleus cells with continuous, involuntary rhythmic contractions & calcium-induced calcium release - high capillary density & mitochondria count

Answer 229

Sinoatrial (SA) Node —> Atrioventricular (AV) Node —> AV bundle (bundle of his) —> Purkinjee fibres

Answer 230

Electrical signals spread through gap junctions

Answer 231

SA node initiates contraction signals - made of pacemaker cells in the upper posterior RA wall - signals spread from SA node via RA/LA to AV node - stimulates

Answer 232

The AV node, located in the RA (right atrial) wall, delays the signal & relays it to ventricles - the delay lets R&L atrial to contract before R&L ventricles - then relays signals to AV bundle

Answer 233

AV bundle relays signal to R&L ventricles which travels along interventricular septum (which then splits into R&L bundle branches) & sends signal to the apex of the heart

Answer 234

Purkinje fibres forming the terminal branches of R&L bundle branches send a signal into the R&L ventricles & spread it through the entire ventricle wall - contraction of R&L ventricles

Answer 235

1.) PNS accesses heart through vagus nerve (cranial nerve X) 2.) PNS carries impulses to SA & AV nodes as it releases Acetylcholine to hyper-polarize cells (brings membrane potential down to decrease threshold & heart-rate) 3.) PNS decreases HR below intrinsic HR (100bpm)

Answer 236

1.) intrinsic = 100bpm 2.) resting = 60-100bpm 3.) elite endurance athletes = 35-45bpm

Answer 237

Opposite effect of the PNS - carries impulses to the SA & AV nodes which release NE for depolarization (increases HR & contractile force) - increases HR above intrinsic HR (determines HR during physical & emotional stress)

Answer 238

Tall mechanical & electrical events that occur during one heart beat - 2 periods; diastole (relaxation phase, chambers fill with blood, & 2x length of systole) & systole (contraction phase to pump blood to body)

Answer 239

1/3 of the cardiac cycle where contraction begins as a result of… - increased ventricular pressure - AV valses closing (heart sound 1 “lub”) - semilunar valve opens & blood is ejected *End-systolic volume (ESV) is the blood remaining in the ventricle *QRS complex to T wave on electrocardiogram

Answer 240

2/3 of the cardiac cycle where relaxation begins due to the ventricular pressure dropping - semilunar (SV) valves close (heart sound 2 “dub”) - AV valves open & ventricle fills 70% passively & 30% by atrial contraction *End-diastolic volume (EDV) = amount of blood in ventricles * T wave to the next QRS complex

Answer 241

The volume of blood pumped out of heart in one heartbeat - occurs during systole where most, not all, blood is ejected - EDV - ESV = SV Eg; 100mL - 40mL = 60mL

Answer 242

The % of EDV pumped - SV / EDV = EF Eg; 60mL/100mL = 0.6 =60% - clinical index of heart contractile function

Answer 243

The total volume of blood that is pumped per minute measured in L/min (Q= HR x SV) - Resting cardiac output = ~4.2 - 5.6 L/min (Average total blood volume is ~5 L & total blood volume circulates once every minute)

Answer 244

The pumping of the heart as one unit

Answer 245

The increased contractility during intense exercise to enhance left ventricle filling *Increases hearts efficiency - Systole: heart twists gradually, storing energy like a spring - Diastole: abrupt untwisting that allows atrial filling (dynamic relation)

Answer 246

1.) Arteries - carry blood away from heart 2.) Arterioles - control blood flow & feed capillaries 3.) Capillaries -site for nutrient & waste connection 4.) Venules - collect blood from capillaries 5.) Veins - carry blood from venules back to heart

Answer 247

Highest pressure in the artery that occurs during systole (contraction) - top number of blood pressure (~110 to 120 mmHg)

Answer 248

The lowest pressure in the artery that occurs during diastole (relaxation) - bottom number of blood pressure (~ 70-80 mmHg)

Answer 249

The average pressure over entire cardiac cycle & is important for pressure differential - MAP = 2/3 DPB + 1/3 SBP

Answer 250

The way your blood flows through your arteries and veins and the forces that affect your blood flow

Answer 251

The force that drives blood flow & provided by heart contraction - blood flows from area of high pressure (LV, & arteries) to are of low pressure (veins, & RA) *pressure gradient = 100mgHg

Answer 252

The force that opposes blood flow & is provided by physical properties of vessels - radius of vessels is most important - controls pressure differences through the body

Answer 253

1.) Change the radius of vessels through; vasoconstriction (smaller diameter) & Vasodilation (larger diameter) 2.) Arterioles (resistance vessels) - site for most VC & VD & responsible for 70-80% of pressure drop from LV to RA

Answer 254

1.) blood flow (BF)s to sites where there is most need - regions of high metabolism have increased BF 2.) @ rest cardiac output (Q) = 5L/min - liver & kidneys receive 50% of Q - skeletal muscle receives ~20% of Q 3.) Heavy exercise (Q = 25 L/min) - exercising muscles receive 80% of Q via VD - flow to liver & kidneys decreases via VC

Answer 255

1.) Metabolic 2.) Endothelial 3.) Myogenic

Answer 256

Metabolic mechanisms (VD) form a buildup of local metabolic by-products such as a decrease in oxygen levels and increase carbon dioxide, K+, H+, & lactic acid

Answer 257

Endothelial mechanisms (mostly VD) include substances secreted by vascular endothelium & includes nitric oxide (NO), prostaglandins (relax smooth muscle), & EDHF (hyperpolarizing)

Answer 258

Local pressure changes that causes VC & VD - increase in pressure causes increased vasoconstriction whereas decreased pressure causes increased vasodilation

Answer 259

Autonomic process where blood flow may be redistributed to a different organ at same level SNS (@autonomic branch) innervates smooth muscle in arteries & Arterioles and increase in sympathetic activity increases VC but decrease in activity leads to decrease in VC

Answer 260

Blood flow to exercising muscle increases to match its metabolic demand This is seen through local alteration of blood flow & improved extraction at tissue level)

Answer 261

Functional Sympatholysis is the inhibition of sympathetic vasoconstriction by reducing vascular responsiveness to adrenergic receptor activation *sympathetic nerve cannot do job bc we’ve inhibited neurotransmitters by EDHF + ND inhibitors *review slide 38

Answer 262

Assist with integrative control of blood pressure - sensitive to changes in arterial pressure - Afferent signals sent from baroreceptors to brain - Efferent signals from brain sent to heart & vessels - Adjustments of arterial pressure are back to normal

Answer 263

1.) One-way venous valves 2.) muscle pump 3.) respiratory pump *upright posture makes venous return to heart more difficult (eg; compared to laying down)

Answer 264

Skeletal muscles contract and increases pressure in vein causing the superior valve to open so the blood can rush through Eg; walking helps activate muscle pump so blood doesn’t pool in legs & decreases risk for deep vein thrombosis

Answer 265

1.) transportation (O2, Nutrients, & waste) 2.) temperature regulation 3.) acid-base (pH) balance

Answer 266

Male = 5-6L Female = 4-5L

Answer 267

1.) Plasma - 55-60% of blood volume 2.) Formed Elements - 40-45% of blood volume - includes… red blood cells, white blood cells, & platelets

Answer 268

- can decrease by 10% with dehydration in heat - can increase by 10% with training & heat acclimation - 90% water, 7% protein, 3% nutrients & ions

Answer 269

- red blood cells (erythrocytes) - 99% - white blood cells (leukocytes) - <1% - platelets - <1%

Answer 270

The total percent of blood volume composed of formed elements

Answer 271

Red blood cells have no nucleus & cannot reproduce - replaced by hematopoiesis - lifespan of 4months - produced & destroyed @ equal rates

Answer 272

An oxygen-transporting protein found in red blood cells - 250million hemoglobin per red blood cell - carries 20mL O2 per 100mL of blood

Answer 273

To carry Oxygen to & remove CO2 from all body tissues

Answer 274

1.) Pulmonary Ventilation 2.) Pulmonary Diffusion 3.) Transport of Gases via Blood 4.) Capillary Diffusion

Answer 275

Process of moving air into & out of the lungs - transport zone & exchange zone - Pathway = nose/mouth > Nasal conchae > pharynx > larynx > trachea > bronchial tree > alveoli

Answer 276

An active process where the diaphragm flattens, ribcage/sternum move up & out, and the thoracic cavity expands thus increasing the volume of thoracic cavity & lungs

Answer 277

Lung volume increases & intrapulmonary pressure decreases - boyles law helps explain this movement - due to pressure difference, air passively rushes in due to pressure difference

Answer 278

Scalenes, sternocleidomastoid, & pectoralis - ribs raise even further

Answer 279

A passive process where inspiratory muscles relax, decreasing lung volume & increasing intrapulmonary pressure - air is forced out of the lungs

Answer 280

Forced breathing, is an active process where internal intercostals pull ribs down - uses latissimus dorsi, Quadratus lumborum, and abdominal muscles to force diaphragm back up

Answer 281

The gas exchange between alveoli and capillaries (alveoli are surrounded by capillaries) - air path = bronchiole tree to alveoli - blood path = right ventricle > pulmonary trunk > arteries > capillaries

Answer 282

1.) Replenishes blood oxygen supply 2.) Removes Carbon dioxide from blood

Answer 283

At rest, lungs receive about 4-6 L of blood/min - RV cardiac output to lungs = LV cardiac output *lung blood flow = systemic blood flow - Blood moves to lungs via Low Pressure Circulation - Lung MAP = 15mmHg vs aortic MAP = 95mmHg - small pressure gradient (15 to 5 mmHg) * resistance much lower as vessel walls thinner

Answer 284

O2 diffusion capacity is the O2 volume that is diffused /min/mmHg of gradient *gradient calculated from capillary mean PO2 (11mmHg) - @ rest = 21mLO2/min/mmHg of gradient OR 231mLO2/min for 11mmHg gradient - @ max exercise = venous O2 levels decrease & PO2 has a bigger gradient (diffusion capacity increases by 3 times)

Answer 285

Limited due to incomplete lung perfusion - only bottom 1/3 of lung perfused with blood & top 2/3 lung surface area has poor gas exchange

Answer 286

Increases with exercise as there is more even lung perfusion as systemic blood pressure rises to open the top 2/3 of lungs for perfusion - gas exchange now occurs over entire lung surface area

Answer 287

Carrying capacity is 20mL O2/100mL blood Approx 1L O2/ 5 L blood

Answer 288

- greater than 98% of O2 is bound to hemoglobin (Hb) in red blood cells (oxyhemoglobin if carrying o2 & deoxyhemoglobin if not carrying) - less than 2% of O2 dissolved in plasma

Answer 289

1.) Blood pH - more acidic = more O2 unloaded @ acidic exercising muscles (Bohr effect as O2Hb curve shifted to right) 2.) Blood Temp - warmer blood causes more tissue O2 unloading during exercise (causes O2Hb curve to shift right)

Answer 290

@ rest, Hb is 98-99% saturated with 0.75 seconds of transit time During exercise, Hb saturation levels lower ( transit time is shorter than at rest)

Answer 291

1.) as bicarbonate ions 2.) dissolved in plasma 3.) bound to Hb (carbaminohemoglobin)

Answer 292

Bicarbonate ions transport 60-70% of CO2 in blood to lungs 1.) CO2 & water forms carbonic acid (H2CO3) - in red blood cells & catalyzed by carbonic anhydrase 2.) Carbonic acid dissociates into bicarbonate - H+ binds to Hb & triggers Bohr Effect - bicarbonate ion diffuses from red blood cells into plasma

Answer 293

A hemoglobin molecule in the blood with CO2 bound to it for transport

Answer 294

20-33% of CO2 transported is bound to Hb - CO2 binds to protein (-globin) part of Hb - deoxyhemoglobin binds CO2 more easily as PCO2 levels affect CO2 binding *higher PCO2 = easier to bind CO2 * lower PCO2 = easier CO2 dissociation

Answer 295

The difference reflects the tissue O2 extraction (higher exteraction = venous O2 lower& difference increases) - Atrial O2 content = 20mL O2/100mL blood - Mixed Venous O2 = 15-16mLO2/100mL blood (rest) or 4-5mLO2/100mL blood (exercise)

Answer 296

Myoglobin - similar structure to hemoglobin but higher affinity for O2

Answer 297

1.) O2 content of blood - represented by PO2 & Hb % saturation 2.) Blood flow - decreased blood flow = decreased opportunity to deliver O2 to tissue… increase exercise = increase blood flow to muscle 3.) Local conditions (pH/Temp) - shift in O2Hb dissociation curve & decreased pH causes increased temp to promote O2 unloading in tissue

Answer 298

1.) maintain bodies homeostatic balance between blood PO2 & PCO2 & pH 2.) coordination between cardiovascular & respiratory systems 3.) coordination via involuntary regulationn

Answer 299

- heart rate - stroke volume - cardiac output - blood pressure - blood flow - blood

Answer 300

Normal ranges of untrained RHR = 60 to 80 bpm Trained Ranges of trained RHR = 30 to 40 bpm * RHR affected by neutral tone, temperature, & altitude * anticipatory response increases heart rate above RHR before exercise starts

Answer 301

Heart rate when exercising is directly proportional to exercise intensity

Answer 302

HR max is the highest HR achieved in all-out effort to volitional fatigue - it’s highly reproducible & see slight decline with age - Estimated HRmax = 220 - age - Better Estimated HRmax = 280 - (0.7 x age)

Answer 303

The point of plateau & the optimal HR for meeting circulatory demands at a given submaximal intensity - increase intensity = increased steady-state HR (2-3mins to adjust) -It is a basis for simple exercise tests estimating aerobic fitness & HRmax

Answer 304

Measure of HR rhythm fluctuates due to continuous changes in sympathetic & parasympathetic balance - influenced by; body core temp, sympathetic nerve activity, respiratory rate, etc - analyzed in respect to frequency (not time)

Answer 305

SV increases with intensity to 40-60% of VO2max (past this is plateau leading to exhaustion) - max exercise SV is approx. double standing SV but only slightly higher than supine SV * supine SV Musca higher than Standing SV due to supine EDV being way larger

Answer 306

1.) increased preload (end-diastolic ventricular stretch) = frank-starling mechanism - increase stretch = increase contraction strength 2.) increased contractility (inherent ventricle property) - increase in epinephrine or NE which increases contractility 3.) decreased after load: aortic resistance

Answer 307

During endurance exercise, there is an increase in mean arterial pressure (MAP) - systolic BP increases in proportion to intensity - diastolic BP has a slight increase or decrease

Answer 308

MAP = Q (cardiac output) x total peripheral resistance (TPR) * Q increases & TPR slightly decreases

Answer 309

cardiac output increases causing an increase in available blood flow - increase in blood flow redirected to areas with greatest metabolic need (working muscle) - blood is shunted away from less active regions by sympathetic vasoconstriction - local vasodilation allows additional blood flow to exercising muscle (triggered by metabolic products)

Answer 310

Cardiovascular drift is associated with increased core temp & dehydration - Stroke Volume decreases as skin blood flow increases & plasma volume/venous return & prelod decrease - Heart Rate drift increases to compensate

Answer 311

Upright exercise causes a decrease in plasma volume to compromise with exercise performance - decreased plasma volume causes increased MAP & capillary hydrostatic pressure - sweating further decreases plasma volume

Answer 312

Hemoconcentration of blood due to decrease in fluid % in blood & increase in cell % (Hematocrit increases up to 50%)

Answer 313

Red blood cell concentration increases as plasma levels decrease - hemoglobin concentration increases, thus increasing O2 carrying capacity

Answer 314

1.) precede metabolic buildup in muscle 2.) HR increases within 1s of onset of exercise 3.) Central Command - higher brain centers & coactivation of motor & cardiovascular centers

Answer 315

First priority is to maintain blood pressure - blood flow is maintained as long as BP is stable - BP prioritized before other needs

Answer 316

There is an immediate increase in ventilation that occurs before muscles contract due to anticipatory responses from central command - second phase of ventilation increase is driven by chemical changes in arterial blood (increase in CO2 & H+ triggers chemoreceptors)

Answer 317

Ventilation increase is proportional to metabolic needs of the muscle - at low intensity, only tidal volume increases but at high exercise ventilation rate increases also

Answer 318

Ventilation recovery occurs several minutes after delay of exercise - regulated by blood pH, PCo2 & temperature

Answer 319

Occurs due to lower airway obstruction & more water being evaporated from airway surface - related to disruption of airway epithelium & injury to microvasculature - results in coughing, wheezing, or dyspnea

Answer 320

Dyspnea is shortness of breathe that is common with poor aerobic fitness & caused by the inability ro adjust to high blood PCO2 & H+ - fatigue in respiratory muscles

Answer 321

Excess ventilation/breatjing that may be anticipatory or anxiety driven - caused by increase in PCO2 gradient between blood & alveoli - must decrease blood PCO2 to decreased drive to breathe (slow breathing)

Answer 322

A potentially dangerous irregularity accompanied with certain exercises that causes the glottis to stay closed (increased intra-abdominal Pressure & intrathoracic Pressure) - the great veins collapse from high pressures causing decrease in venous return, decreased cardiac output, & decreased arterial BP

Answer 323

The point where Litres of air breathed is greater than Litres of O2 consumed - associated with lactate threshold and increased PCO2

Answer 324

Ventilation normally not a limiting factor as respiratory muscles are very fatigue resistant (account for 10% of VO2 & 15% of cardiac output [Q] during exercise)