Integration 2 Flashcards
1
Q
What are characteristics of strength/resistance athletes?
A
High static component
Short duration
Immense power
Uses ATP store and ATP-CP system
2
Q
What are characteristics of aerobic/endurance athletes?
A
High dynamic component
Long duration
Steady high intensity
Uses aerobic system
3
Q
Why do active muscles have an increased requirement of oxygen during exercise?
A
Because muscles are using up ATP, there is an increased cardiac output and increased ventilation (plus more).
4
Q
What makes exercise become easier over time?
A
System being made more efficient due to body adaptations to repeated exposure to the stress (remodelling)
5
Q
What are the three key points about cardiac remodelling?
A
Increased heart mass
Reversible
No fibrosis
6
Q
What is meant by there is “no fibrosis” in cardiac remodelling?
A
No scar tissue formation (when exposed to a stress some cells will die and be replaced with no fibrotic cells - this is favourable).
7
Q
What is the physiological cardiac remodelling of an endurance athlete (e.g., runner / swimmer)?
A
Thickening of the LV walls
LV dilation
8
Q
What is the physiological cardiac remodelling of a strength athlete (e.g., weightlifter, wrestler)?
A
Thickening of LV wall
Mild LV dilation
9
Q
What is the physiological cardiac remodelling of a combination athlete?
A
Gross thickening of LV walls
LV dilation
10
Q
What is a combination athlete?
A
An athlete that trains in both cardio and resistance training
E.g., rower or canoeist
11
Q
Is physiological remodelling reversible?
A
Yes
12
Q
What is concentric hypertrophy?
A
An increase in the size of cardiomyocytes due to an increase in the number of sarcomeres added in PARALLEL
(= inward increase in the size of cardiomyocytes meaning thicker wall reducing lumen size).
13
Q
What is increased during concentric hypertrophy?
A
Increased CSA of muscle fibres (becomes broader)
Increases contractile strength of each individual cell
14
Q
How is concentric hypertrophy and after load related?
A
Concentric hypertrophy is a result of afterload
Increased after load causes the heart, particularly the LV, to work harder to pump blood against this higher resistance.
This leads to increased wall stress, compensatory cardiac remodelling and thicker myocardium = concentric hypertrophy.
15
Q
What is after load?
A
The ventricle wall tension developed to over aortic pressure.
Afterload refers to the pressure the heart must overcome to eject blood during systole (the contraction phase). It’s primarily determined by the resistance in the arteries (e.g., high blood pressure or conditions like aortic stenosis).
16
Q
What type of training predominately causes concentric hypertrophy?
A
Resistance / Strength exercise training
17
Q
How much can strength / resistance exercise training increase BP?
A
up to x3 increase = sudden elevations in BP
18
Q
What does pressure overload cause?
A
Concentric Hypertrophy
19
Q
What is eccentric hypertrophy?
A
Increased size of cardiomyocytes due to an increase number of sarcomeres added in SERIES (Z line to Z line).
= outward increase in the size of cardiomyocytes wall proportional to the increase in lumen size = elongation
20
Q
What is increased by eccentric hypertrophy?
A
Increased contractile strength of each individual cell
21
Q
What is preload?
A
Preload refers to the amount of stretch in the ventricular walls at the end of diastole, just before contraction. It is determined by the volume of blood returning to the heart. A higher blood volume increases the stretch on the heart’s walls, leading to greater preload.
Greater preload = greater EDV
22
Q
How is preload and eccentric hypertrophy related?
A
Eccentric hypertrophy is a result of increased preload
23
Q
How is volume overload induced?
A
By increasing preload
24
Q
How does increased preload cause eccentric hypertrophy?
A
Passively stretches the cardiomyocytes putting stress on the proteins
Remodelling to elongates muscle fibres
Proportionally increased wall thickness to chamber dilation
25
What type of exercise predominantly results in eccentric hypertrophy?
Endurance/aerobic exercise training
(sustained high intensity and highly dynamic exercise)
26
How much can cardiac output be increased from 5-6Lmin during endurance / aerobic exercise training?
Up to around 40 L/min
27
What does volume overload with slight pressure overload cause?
Increase work of left ventricle
results in elongation of muscle fibres
Increased thickness of LV wall proportional to increased chamber diameter
28
How does chamber dilation increase SV?
With chamber dilation there is a larger EDV
A larger EDV increases SV
29
How does more sarcomeres result in a larger SV?
More sarcomeres increase the force of left ventricle therefore increased SV
30
How does training effect SV?
Trained athletes will have a greater SV than untrained athletes
31
What is an easy and non-invasive method of tracking training progress?
Using HR as a proxy for fitness
Lower HR indicates a higher level of aerobic fitness
32
What does watts measure?
A measure of power output.
A trained athlete will be able to perform at higher exercise intensity (produce more watts) before reaching their max HR.
E.g., In activities like cycling, watts measures the power applied to the pedals. The more watts a cyclist can sustain, the faster and more efficiently they can ride. For example, producing higher watts allows a cyclist to climb hills more easily, accelerate faster, and maintain higher speeds over time.
33
How does aerobic/endurance training affect max HR?
It doesn't as max HR is determined by age - instead what it does is determine the intensity of exercise you can perform at your given max HR.
E.g., how many watts you can produce before reaching max HR
34
What are the vascular adaptation to aerobic exercise?
Reduced arterial stiffness and increased blood volume
35
What causes a reduction of arterial stiffness as a result of aerobic exercise?
A higher SV = larger expansion of the vessel wall = increased compliance enables better dampening of pulsatility (to ensure there is laminar flow).
36
What causes there to be an increase in blood volume as a result of aerobic exercise?
Increase in aldosterone and antidiuretic hormone release causing sodium reabsorption and water retention and Increase in plasma proteins = increased plasma volume.
Increase RBC count as well due to acute increase of erythropoietin release post-exercise
37
When is EPO released?
During acute periods after exercise
38
What are the 3 skeletal muscle adaptions to aerobic exercise?
Conversion of more Type 1 (slow twitch) fibres (fast to type1 or type2a intermediate)
Increased mitochondrial content within muscles fibres
Increase capillary density
39
What is the result of more type 1 fibres?
Increased number of oxidative enzymes
More myoglobin (oxygen storage)
40
What does increase mitochondrial content within muscle fibres result in?
oxygen consumption capacity because more ATP
41
How much can training increase mitochondrial content within a muscle fibre?
x2
42
What is VEGF?
Vascular Endothelial Growth Factor
43
What does athletes strategic tapering before an event have to do with mitochondrial content ?
Mitochondrial content reflects training status - because it increases and decrease with training. So whilst it is important for athletes to taper to ensure their bodies are fresh for an event this needs to be done strategically (e.g., not for too long or too far before event) otherwise they risk losing adaptations and their benefit.
44
What promotes angiogenesis?
An increase in vascular endothelial growth factor (VEGF) hormone causes angiogenesis which is the formation of new blood vessels
45
What is angiogenesis?
The production of blood vessels.
46
What are the structural changes to lungs/airways as a result of aerobic exercise?
There are none
47
what are the respiratory systems adaptations to aerobic exercise?
Stronger respiratory muscles
Increased pulmonary capillary density around alveoli
48
What causes an increase in lung capacity as a result of aerobic exercise?
Stronger respiratory muscles
49
How does aerobic exercise causes an increase in the SA for gas exchange?
The increase in pulmonary capillary density around alveoli means that there is an increase SA for gas exchange
50
How is Vo2-max improved in endurance (aerobic) athletes?
(1) Improved oxygen delivery to the tissues
(2) Improved oxygen uptake within skeletal muscles
51
How is oxygen delivery to tissues improved with endurance training?
increased cardiac output
increase number of RC
increased skeletal muscle capillary density
52
What is anaerobic threshold?
The threshold is the point when the body can no longer remove the lactic acid at a rate the body is producing it at
53
How is anaerobic threshold affected with endurance athletes?
The push the threshold higher - meaning it takes a higher exercise intensity (work rate/more watts) to reach the threshold
= improved endurance capacity
= worker harder for longer
54
How does oxidative phosphorylation in skeletal muscle become more efficient as a result of endurance training?
Because there is more mitochondria and oxidative enzymes it means that it works more efficiently
55
What is an example of an oxidative enzyme in skeletal muscle?
Lactate dehydrogenase
56
What are ergogenic aids?
Any substance or technique used to enhance athletic performance
57
What is the aim of ergogenic aids?
To increase the physiological capacity of a particular body system
58
What are the four ways that ergogenic aids provide benefits?
Increase speed of recovery
Decrease the onset of fatigue
Decrease the perception of fatigue
Increase motivation or aggression
59
What are the three classes of exogenic aids?
Mechanical Aids
Pharmacological Aids
Physiological Aids
60
What are the examples of mechanical aids?
Altitude training
Compression garments
Nasal strips and dilators
61
What are examples of illegal pharmacological aids?
Anabolic androgenic steroids
Cobalt Supplementation
Synthetic EPO
62
What are examples of permitted supplements/pharmacological aids?
Caffeine
Beetroot juice
Creatine
Bicarbonate loading
Beta-alanine supplementation
63
What are examples of physiological aids?
Acupuncture and cupping therapy
Blood doping
64
How does high altitude enhance performance?
At high altitude there is a lower atmospheric oxygen pressure meaning there is a reduced arterial Partial pressure of O2.
Short term this increases heart and breathing rates to compensate for hypoxic environment.
Long term the kidneys upregulate EPO to increase RBC production. With more RBC there is an increase in oxygen carrying capacity of the blood when you return to perform at sea level. With increased oxygen carrying capacity you have improved endurance performance because there is more substrate for oxidative metabolism.
Also aids in recovery.
65
How do compression garments enhance performance?
Compression garments compression the muscle and surrounding tissues. This reduces muscle oscillations preventing damage.
It also increases joint awareness as there is more sensory information for better alignment an mind to muscle engagement.
Compression may also held with blood flow to working muscles (improve muscle oxygenation) and venous return by enhancing skeletal muscle pump mechanisms.
66
How do nasal strips and dilators enhance performance?
Physically open the nostrils by lifting the cartilage - strips are on the outside of the nose and pulling the cartilage up whereas dilators are on the inside and push the cartilage up.
By doing this is creates a more patent airway reducing resistance to the airflow. It aims to improve ventilation and oxygen uptake.
However there is limited evidence that this actually enhances performance as resistance is greatest in bronchioles which we cannot get to.
67
Who might benefit most from nasal strips and dilators?
Those with nasal passageway issues such as nasal congestion or deviated septum.
68
What are anabolic androgenic steroids a synthetic derivative of?
Testosterone
69
How are anabolic androgenic steroids commonly administrated?
Via intramuscular injections
70
When were anabolic androgenic steroids banned?
1976
71
How does the administration of anabolic androgenic steroids enhance performance?
It acts in the same way that testosterone does:
In the kidney it causes the stimulation of EPO production which increases RBC
In the bone marrow it increases bone strength which prevents injury
In the brain it increases aggressive behaviour and motivation
In muscles it increases muscle mass and strength and carnosine levels.
72
What are the secondary characteristics associated with testosterone (steroids)?
Hair growth and deepening of the voice due to thickened vocal cords.
73
What is carnosine and what does it do?
It is a protein that buffers H+ ions in the blood (therefore reduces lactic acid build up)
74
What did Cobalt supplementation treat in the 1940's?
Anemia (because it upregulates RBCs)
75
How does cobalt supplementation upregulate RBC's?
It stabilises hypoxic inducible factor (HIF) which stimulates EPO gene transpiration and production in the kidneys - increases RBC's and increases O2 carrying capacity.
76
How much Cobalt is equivalent to 8-9 days at altitude?
oral dose of 5mg/day for 3 weeks
77
What are the risks of cobalt supplementation?
Risk of toxicity and organ damage - hence it was banned in 2015.
78
What is synthetic erythropoietin?
A synthetic (imitation of the natural product made by chemical synthesis) version of the hormone EPO - given by intravenous injection to act directly on bone marrow
79
Where does synthetic EPO bind?
To receptors on erythroid stem cells in the bone marrow
80
What is the pathway from myeloid cells to RBCs (erythrocytes)?
Myeloid cells > proeryuthrobast > erythroblast > reticulocyte > RBC (erythrocyte)
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81
What is the normal PCV for males and females respectively?
Males 42-50%
Females 36-44%
82
What is polycythemia?
abnormally high PCV of RBC's
83
Why are TDF cyclist not allowed to ride if PCV greater than 50%?
Because it suggests blood doping and dangerous to exercise at such high intensity with such thick blood
84
Why is thickened blood dangerous for athletes?
Increases blood viscosity which increases resistance to blood flow and reduced flow increases risk of blood coagulation (clotting).
Elevates blood pressure = which increases after load and ventricle wall stress.
After exercising you are dehydrated and loss of plasma volume increase PCV even more post-exercise
Athletes already have a low resting HR an then to add these factors there is a heightened risk of blood clots - this risk is increased even more if EPO injected.
85
How does caffeine enhance performance?
It is a stimulant on the brain (caffeine is an adenosine receptor antagonist) - therefore its effects are mental not physical.
It reduces the perception of fatigue, increases mental alertness and concentration therefore allows increase duration of performance.
86
What are examples of caffeine supplements?
Pre-workout formula
Caffeine gels
Energy drinks
87
How much caffeine is found to be beneficial for endurance in both aerobic an strength/resistance exercise?
3-6 mg/kg (equivalent to 3-5 red bull Cains for a. 7-kg individual)
88
How does beetroot juice enhance performance?
Contains high level of nitrate, the precursor of nitric oxide (NO) - nitrate in hypoxic environment gets converted to nitric oxide which a vasodilator.
Vasodilation promotes increased local blood flow and O2 delivery promoting ATP - also good for recovery to replenish ATP stores.
More efficient mitochondria improving O2 utilisation
89
How does creatine enhance performance?
Increases PCr stores within muscle - During short duration, high intensity exercises PCr is utilised to produce ATP.
greater quantity of ATP means more energy for increases powerful output by the muscle.
Aids in recovery and replenishing muscles phosphocreatine stores post exercise.
90
What type of athletes is creatine most beneficial for?
Athletes performing explosive, short duration exercises such as resistance/strength-training or sprinting.
91
What is a common way to bicarbonate load?
Consumption of baking soda = NaHCO3 soda bicarbonate power
92
How does bicarbonate loading enhance performance?
Buffers excess blood H+ produced during exercise which acts to increase anaerobic threshold by prolonging lactic acid build up
93
What limits the benefit of bicarbonate loading?
Gut discomfort (CO2 build up in the stomach causes bloating and acid neutralisation effects gut function).
94
What activities is bicarbonate loading beneficial for?
Activities that rely on anaerobic glycolysis as it increases time to exhaustion in high intensity exercise
95
How does beta-alanine enhance performance?
Caroline buffers H+ within skeletal muscles which prevents lactic acid build up therefore improves anaerobic threshold and increases exercise duration.
96
What type of athletes is beta-alanine most beneficial for?
Most beneficial for athletes performing between 1-10 minutes (middle distance athletes) because they are using anaerobic glycolysis
97
How does acupuncture and cupping therapies enhance performance?
Aid in recovery
= promotes local blood flow which increases oxygenation and assists with metabolite/waste removal
= muscle regeneration which reduces delayed onset of muscle soreness
= releases contraction knots
98
How does blood doping work?
Athletes collect and store own blood during off season (then body will adapt to less RBC by creating more) and then they transfuse it back into body to instantly increase RBC count.
99
When was blood doping banned and how is it detected?
1986 - current no detection method but elevated haemltocrit indication of blood doping therefore athletes will get random blood test to aid to biological blood passport to monitor spikes.
100
What was suspicious in Lance Armstrongs biological passport?
Mismatch between reticulocyte levels and Hgb levels
Reticulocyte level should increase to replace RBC damaged during exercise.
101
What are reticulocytes?
An immature RBC (one step pre RBC)
102
Is exercise always good?
Exercise is beneficial to our physiology by reducing your risk of cardiovascular disease and all cause morality but it is al about balance - if you exercise too much at high intensity without adequate rest then it can be harmful.
103
How does cardiac remodelling change when exercising without rest?
It becomes pathological because can lead to arrhythmia (irregular depolarisation/contraction).
104
What are two types of arrhythmia?
Atria Fibrillation (irregular atria contraction)
Ventricular Tachycardia (irregular ventricular contraction)
105
In what classes of people has it been found that running reduces mortality?
All subgroups (specially the study showed that it reduces mortality in both men and women, of all ages, all weights, both healthy and unhealthy individuals, smokers and nonsmokers and those who do and don't consume alcohol).
106
What is the percentage reduction in the rate of all cause mortality incidences in runners compared with non runners?
30%
107
What is hypertension?
High blood pressure causes a high force pushing against the artery walls causing them to thicken (LV).
108
If you know that someone is a non runner does it mean you can predict a decreased life expectancy?
Yes - being a non runner (non physcial activity of all kinds) is as much a mortality predictor as other factors such as hypertension/smoking/diabetes.
109
What is a dose dependant relationship?
Whether results change in response to changing dosage.
E.g., If the effects change when the dose (frequency, speed or distance) of running is changed, the effects are said to be dose-dependent.
110
Is there a dose dependant relationship between running and obesity?
Yes - the more you run the more the prevalence of obesity drops
111
What variables is there, and is there not, a dose dependant relationship to running with?
Dose dependant: Obesity
Not dose dependant: hypertension, diabetes, hypocholesterolemia, abnormal ECG.
112
Is there a dose dependant relationship between running time and hypertension?
No - there is a intitial drop in the first few quintiles and then it increases again.
113
With more extreme exercise how is survival from CVD effected?
The rate of CVD mortality is reduced for runners regardless of how fast or far - but greatest effect intiially and then with more extreme exercise behaviours show less of a benefit in survival.
U shaped graphs = meaning that extremities didn;t improve survival as much as lower quintile.
114
If you changed behaviour to start running what is going to be reduced?
The rate of all cause and CVD morality.
*But it is not just running - any form of physical activity improves chances of survival.
115
What is the perecentage reduction in incidence of all cause maorlity as a result of low levels of physical activity?
20%
116
Is high or low intensity training best for improving Vo2max?
High intensity - aerobic exercise training is best for improving Vo2max.
117
What is the relationship between left venticualr mass and Vo2max?
Positive linear relationship - As LVM increases VO2max increases.
This is because a higher LVM leads to increased stroke volume and CO = allows more oxygenated blood to reach the muscles, enahncing body’s ability to perform at higher intensities for longer period all of which is crucial for improving/related to VO2max.
118
What is hypertrophy?
Increased size of organ/tissue due to enlargement of cells
119
What are the three types of pathological cardiac remodeling?
Hypertension
Dilated cardiomyopathy
Hypertrophic cardiomyopathy
120
What is happening during dilated cardiomyopathy?
Thinning of LV walls causing signficiant LV dilation
121
What is hypertrophic cardiomyopathy?
The gross thickening of LV walls but there is no dilation/decrease in LV chamber size
122
What is right bundle branch block (RBBB)?
The delayed depolarisation of the right venticle due to a block of some sorts in the right bundle branch conduction pathway.
Results in the left ventricle contracting as normal and the right ventricle contraction lagging behind.
123
What is the difference between complete and incomplete RBBB?
Complete RBBB is pathological whereas imcomplete RBBB is asymptomatic and therefore classed as nonpathological.
124
What is complete RBBB?
Where the left and right ventricle contraction is out of sync
125
What is incomplete RBBB?
It is the delayed depolarisation of the RV as a result of hypertrophy (stretching of RV purkinje fibers) - which is prevalent in 10-20% of elite athletes.
But there is also LV hypertrophy due to there being more tissues to innervate so that it takes longer for depolartion to reach to RV.
Therefore, cancel each other out and contraction is not out of sync.
126
Incomplete RBBB is prevalent in 10-20% of elite athletes - what type of athletes is this most common in?
Endurance
127
What is RV arrhythmogenic remodeling?
Arrhythmogenic remodeling of the right ventricle refers to structural and electrical changes in the RV that increase the likelihood of developing arrhythmias (abnormal heart rhythms).
It is the result of the RV being more sensitive to afterload - RV is more sensitive beause pulmonary vasculature is already stretchy/compliant in order to function at lower pressures than the systemic/left side of the heart. Vasculature can only become so compliant and because RV already compliant is has a lesser capacity to compensate for increases in afterload than the left side which has a lower base compliance.
128
What causes myocardial injury in RV?
The RV being exposed to high stress (high intentosty exercise) causes RV hypertrophy and dialtion of the chamber - when this occurs for long periods of time without rest this can result in myocardial injury.
129
What is myocardial injury?
Cell death
130
Explain how RV stress can result in fibrosis?
Prolonged RV stress = myocardial injury.
The cell that have died are then replaced with ECM (fibrotic tissue).
131
How does fibrosis cause arrhythmia?
Because fibrotic tissue components such as collagen cannont conduct electricity - therefore fibrosis effects the eclectrical conduction pathway = arrhythmia.
132
What is arrhythmia?
Disruption to normal electrical conduction through the heart (effects contraction).
133
Is the RV or LV SV more impaired as a result of enhanced afterload?
RV more sensitive - because RV already a low compliant, low resistant system (thiner walls).
134
What is ventricular tachycardia?
Arrythmia arising from the ventricles: atrial contract as normal but ventricular contraction is irregular (not from top to bottom or in sync).
Involves premature venticular contractions at a high rate due to ventrciualr myocytes initiating rapid/ectopic beats (distinct to pacemaker activity).
As a result of a high rate of ventricular contraction there is less time to fill the ventricule = reduced EDV = reduced SV = reduced CO and flow.
135
What happens if ventricular tachycardia is left untreated?
Death (heart attack)
136
What is atrial fibrillation?
Arrhythmia arising from the atria of the heart (inhibited atrial top up).
At rest this is not probelmatic but when exercising atrial top up amounts to 30-50% of EDV therefore it does become problematic.
137
What class of people is atrial fibrillation common in and why?
High performance endurance athletes - they are 5 times more likely to experience it due to the high haemodynamic load on the atria as a result of high CO, stretched in atrial wall and atrial remodeling/enlargement caused by intense exercise
138
Does Atrial fibrillation effect you whilst exercising or at rest?
During exercise - it is benign at rest
