There are two types of studies used to assess the effects of exercise on physiological systems, what are they?
Cross-sectional studies, and b) Longitudinal studies.
Longitudinal studies are also known as _________________.
Training studies
In terms of training the anaerobic energy systems, the most important factor is __________________________.
Intensity
Application of the overload principle is carried out in interval training by manipulating what four factors?
1.Intensity of exercise
2.Duration of the work interval
3.Duration of the relief interval
4.The number of repetitions per session.
In addition to the four factors outlined in the lecture, what other factor discussed in the lecture is also known to play a role in the application of overload during interval training?
The type of recovery also plays a role.
In the lecture (lecture 6) four major methods for determining training intensity were discussed, what were these?
a) Use of blood lactates
b) heart rate
c) RPE
d) training pace (velocity).
During the first 5 to 8 seconds of maximal exercise the predominant source of energy is ____________________________.
PCr (phosphocreatine).
During 1 to 2 seconds of maximal intensity exercise the predominant source of energy is ______________________.
ATP (adenosine triphosphate).
What should the minimum work to rest ratio be for the following energy systems? a) ATP/PC, b) glycolysis, and c) the aerobic system.
a) 1:3
b) 1:2
c) 1:1 or less.
When performing interval training which energy system(s) seem to be better served when employing a rest-relief (passive recovery)?
The ATP-PC and aerobic systems.
What type of recovery seems to be the method of choice when the goal is improve lactate tolerance?
Work-relief (also known as active recovery).
List as many of the metabolic adaptations to endurance training as you can remember from the specific slide in topic 6.
1. larger and more numerous mitochondria
2. increase in the quantity of aerobic enzymes
3. increase in the capacity to mobilise, deliver and oxidise lipid
4. increase glycogen storage
5. shift in the fibre-type characteristics to become more oxidative
6. selective hypertrophy of trained fibres (e.g. type I larger than type II in endurance athletes)
Larger and more numerous mitochondria
Increase in the quantity of aerobic enzymes
Increase in the capacity to mobilise, deliver and oxidise lipid
Increased glycogen storage
Shift in the fibre-type characteristics to become more oxidative
Selective hypertrophy of trained fibres (eg. Type I larger than Type II in
endurance athletes)
What substance facilitates the transport of long-chain fatty acids into the mitochondria? (although not shown on the slides I mentioned this in relation to metabolic adaptations to endurance training).
Carnitine.
With resistance training what fibre type conversion is known to occur?
Type IIB (or IIAB) (fast twitch fatiguable) to type IIA (fast twitch fatigue resistant) and eventually to type I (slow twitch)
What was taught in the lecture about the effect of interval training for 6 second bouts versus 30 second bouts with respect to creatine kinase (CK) and myokinase (MK) enzyme changes? Remember that training refers to chronic interval training (e.g. several months) versus an acute bout (i.e. one single session).
Both CK and MK show greater increases in activity following training involving 30 second bouts.
What is the effect on ATP and PCr stores after a training program?
They both increase after training
What is the effect of a specifically designed training program (ie. anaerobic) on the key regulatory enzyme of glycolysis, phosphofructokinase (PFK)?
It increases in activity.
What are the four main ways for the body to lose
heat and which one is the most important during
exercise?
1. Radiation
2. Conduction
3. Convection
4. Evaporation- sweating most important
Why is the level of humidity important in the risk of
exercise-induced hyperthermia?
1. Provides increased strain on the thermoregulatory system
2. Cutaneous vasodilation increases skin temp and therefore heat loss via sweating
3. Sets up competition for cardiac output between working muscles and skin
4. Limits capacity for work and increases HR for a given workload
5. Likely causes central fatigue (increased mental errors)
Differentiate between heat cramps, heat exhaustion
and heat stroke.
2. heat exhaustion: symptoms include; pale and cool skin; weakness; headache; nausea
3.heat stroke: (most severe): symptoms include; strong and rapid pulse; hot and dry skin (not sweating); confusion
What is the purpose of the wet-bulb globe
temperature (WBGT)?
is a heat stress indicator that considers the effects of temperature, humidity, and radiant energy.
What are the physiological adaptations which allow a
person to acclimatise to exercise in hot/humid
Several days of activity in a hot environment will lead to improved heat tolerance and performance:
Adaptations:
-sweat rate increases
-earlier onset of sweating
-plasma volume increases
-NaCl content of sweat decreases
-cutaneous blood flow decreases
-Muscle glycogen utilisation decreases
Once acclimatisation occurs, benefits last for several
weeks
What are adaptations in sweat glands that allows
acclimatised individuals to increase evaporative cooling?
-2-4,000,000 sweat glands open onto skin surface
- under nervous control
- secrete a hypotonic solution
How does the hypothalamus act as a controller of body
temperature?
(NEGATIVE FEEDBACK LOOP)
1. Increase blood and internal temperature
2. Impulse goes to hypothalamus
3. Vasodilation occurs in the skin blood vessels so more heat is lost across the skin
4. Sweat glands become more active, increasing evaporative heat loss
5. Body temperature decreases
Give two conditions which cause the hypothalamic “setpoint”
for body temperature to be raised?
1. metabolic heat
2. environmental heat
Approximately what percentage of total heat loss does evaporation contribute to the body at rest in thermoneutral conditions?
25%
Give four factors which effect an individual’s tolerance
to heat exposure.
1. Acclimatisation/training
2. Aged/older people: have poor thermoregulatory efficiency and decreased thirst
3. youth: have poor thermoregulatory efficiency
4. gender: females sweat less than males
The rate of gastric emptying of fluids into the small intestine is influenced by:
A) the volume of fluid ingested
Which of the following represents a physiological buffer of the body?
A) bicarbonate
Ingestion of the following substance has been used as an ergogenic aid to improve the buffering capacity of the body:
Sodium Bicarbonate
The most important plasma buffer is:
heamoglobin
Name three of the main electrolytes of the body and give their functions.
1. Sodium:
2. Chloride:
3. Potassium:
Main role is to maintain electrical gradients across membranes – vital for nerve transmition and muscle contraction
List, in descending order, the four most important chemical buffers in the blood
1. Protein (-Hb) 0.8 (least important)
2. Phosphate 0.3
3.Bicarbonate 1.0
4. haemoglobin 1.5 (most important)
Why is blood lactate lower than active muscle lactate during heavy exercise?
when blood lactate falls below 7.0 this can only be tolerated briefly (dizziness, headache, nausea). pH can fall lower than blood lactate.
Define fatigue.
Tiredness (sensation/ psychological) & Decrement in force/power output (physical)
knowledge of the predominant energy system for a given activity is required to approach the two main prinicples of physical training. These two principles are?
Specificity and Overload
to optimise specificity and overload of training, which 3 training principles need to be considered and which is the most important for training the anaerobic system?
intensity, duration and frequence - intensity most important for anaerobic
define interval training
a series of repeated bouts of exercise alternated with periods of rest (work interval and relief interval)
depending on "how" you do the interval training will depend on what?
which energy system you want to train
True or false: an increase in the intensity of work causes an overload of the energy system being utilized in each case
True
what are the 4 principles of interval training?
1. intensity of the exercise
2. duration of the work interval
3. duration of the relief interval
4. number of repetitions per session
How can the use of Blood Lactates be used to determine Interval training intensity?
quantification of the level of anaerobic metabolism
must be individualised
will vary with training status
Blood lactate results from interval training are often combined with the use of what 3 things?
1. heart rate
2. RPE
3. training pace/velocity
Why is HR combined with BLA when determining interval training intensity and what should you be mindful of?
HR is a good indication of relative exercise intensity, however, you should be mindful that training will alter this relationship
Why is RPE combined with BLA when determining interval training intensity?
subjects can be trained to recognise perceptual changes associated with lactate accumulation
Why is training pace/velocity combined with BLA when determining interval training intensity and what should you be mindful of?
because its quick and easy:
however, it may/may not take into account individual differences (MAS vs sprinting)
What are the 3 main claims that support the use of amphetamines use in sport?
Increased concentration adn alertness
Increased motivation and aggression
Decreased feelings of fatigue
Name 4 negative effects of amphetamines use
1. Hightened SENSE of ability
2. Addiction
3. Psychotic effects e.g. nervousness , paranoia
4. Increase strain on CV system by increasing BP and HR – irregular ECG trace
Which of these drugs is not banned during competition:
B) Caffeine
What are ephedrine and psuedoephedrine both mild forms of?
Adrenaline
Clenbuterol increases:
B) muscle mass
Which legal drug has a milder, similar effect on the body to amphetamines,
caffeine
Why are beta-blockers effective in sports such as darts and pistol shooting?
Reduces anxiety and decreases HR and BP in sports where anxiety and tremor can negatively effect performance
Name 5 “positive” effects of using amphetamines
Increased state of arousal and self confidence
Faster decision making and reaction time
Decreased sense of fatigue
Increased HR,BP, and blood flow to muscles
Increase blood glucose and FFA
What is pH?
A quantitative measure of the acidity of alkalinity of a solution
What is the minimum pH level the body can endure and where is it likely to be found?
~6.80, muscles
What is the maximum pH levels the body can endure?
What is the maximum pH levels the body can endure?
~7.80 (clinical alkosis = 7.5)
What is the normal range of pH within the body?
7.35-7.45
What are buffers?
Substances that resist change in pH: can be chemical or physiological
Order these chemical buffers from highest relative buffering capacity to the last:
Phosphate, Bicarbonate, Protein, Haemoglobin
Haemoglobin
Bicarbonate
Phosphate
Protein
What is Carnosine?
A chemical buffer
Strong antioxidant located in the muscle
Dipeptide of the amino acids beta-alanine and histdine
Not effectively absorbed and hydrolysed to amino acids
What is the most common way of measuring H+ concentration?
by measuring blood lactate
What is the formula for a carbonic acid ion?
H2CO3
What is the formula for bicarbonate?
HCO3-
What is the equation for acidosis/alkalosis?
H+ + HCO3- <=> H2CO3 <=> H2O + CO2 (Hydrogen ion + Bicarbonate <=> carbonic acid <=> Water + carbon dioxide)
If you held your breath, and did not get rid of CO2, what would happen in the body?
you would produce more hydrogen ions (H+)
if you were to hyperventilate, and breathed out too much CO2 what would happen to the hydrogen ions?
breathing of more CO2 molecules, because of this eventually you would get rid of more H+, eventually you're blood would become basic
Why would you give someone who is hyperventilating a paper bag to breath in/out of?
So that they start to re-absorb CO2 and neutralise pH
Why does someone feel dizzy when they hyperventilate?
because you start breathing off the CO2, it causes all the blood vessels in the brain to vasoconstrict, not enough blood goes to the head and then you would get dizzy/pass out
True or False? High thermal stress decreases ventilation
False
Why does exercise in the heat effect pH in the body?
It makes you hyperventilate and therefore H+ concentration goes down, pH becomes increased.
Is the renal buffering system for short term or long term adjustments in body pH?
long term
why would you need to urinate more at altitude?
to try and get rid of hydrogen ions to rebalance pH but then we become dehydrated
what are the sideeffects of plasma levels dropping bellow 7.0
dizziness, headache, nausea (brain!)
True or false, muscle lactate is always greater than blood lactate
TRUE
The Cori Cycle involves the movement of lactate and blood glucose between the _____ and the ______
muscles and liver
What are the 6 predisposing factors of heat illnesses?
sleep loss
generalised fatigue
illness
motivation
body size
fitness
uncompensable heat stress
Of the heat illnesses, what % is accounted for by heat exhaustion and heat syncope?
71.8%
Of the heat illnesses, what % is accounted for by heat stroke?
9.0%
Of the heat illnesses, what % is accounted for by heat cramps?
19.0%
What are the 2 different ways of tolerating heat?
genetics and acclimatisation
Which genotype is supposed to be associated with heat tollerance?
the ACE genotype
What are the 5 main mechanisms by which body fluid deficit may cause fatigue?
Decreased muscle blood flow is a mechanism by which body fluid deficit causes fatigue, what are the 3 components that are effected by a decreased muscle blood flow?
Decreased nutrient delivery (e.g. glycogen)
Decreased metabolite removal
Altered cellular metabolism
Exercising in the heat results in an increase in the contribution from which energy system?
Anaerobic metabolism
What are the types of sports where you would lose the most water?
American football and Tennis
Why would someone playing tennis lose so much water? (from sweating)
because there is no wind within the arena to cool the body via convection... therefore the body continues to sweat in an attempt to cool the body
Which 5 factors influence fatigue (via fluid loss)?
Event duration
Intensity
Environment
Fluid colume
Nutrient Content
For exercise lasting less than an hour, is it important to consume CHO as well as fluids?
No
Where is food and fluid ABSORBED?
the small intestine, NOT the stomach
The rate at which fluids leave the stomach and is absorbed into the body (gastric emptying) is affected by:
stomach volume (full is faster)
fluid/food consumption - just water is passed faster than something that is 5-10% CHO (higher than 10% too slow)
temperature (cold is best)
exercise intensity (above 70%VO2max= cut off blood flow to the stomach/small intestine)
why does gastric emptying slow during exercise higher than 70% VO2max?
blood flow to the stomach and small intestine is reduced, therefore gastric emptying is slower
what is the optimum CHO level for fluids, seen in gatoraid and poweraid?
8-10% CHO
Which would empty fastest into the small intestine? A solid meal or liquid meal?
A liquid meal
What are the 3 electrolytes found in sports drinks?
Sodium, Potassium and Chloride
What is the main role of body electrolytes?
To maintain electrical gradients across membranes vital for nerve transmission & Muscle contraction
What is hyPOnatraemia?
low plasma/ tissue Na+ levels
what is hyPERkalaemia
high plasma/tissue K+ levels
What causes hyponatremia?
due to excess water consumption, or poor water handling by excess ADH secretion
True or False, the most recent fluid guidelines suggest that fluid replacement should equal fluid loss
false, can cause hyponatraemia. Instead, drink to level of thirst
If exercise is less than 1 hr in duration, what are the best reccomendations of type of fluid intake?
cold water is best
If exercise is greater than 1 hr in duration, what are the best reccomendations of type of fluid intake?
~5% CHO + low concentration electrolyte (e.g. NaCl) drink
What 5 things effects Sweat Electrolytes?
Sweat Volume
Onset of Sweating
Sweat Electrolytes
Acclimatisation
Sports Drinks
What is Fatigue?
Tiredness (psychological/sensation)
Decrement in force or power output (physical)
What are the 4 multidisciplinary components of fatigue study?
Physiologists
Neruophysiologists
Biomechanists
Psychologists
The cardiovascular/anaerobic model of fatigue suggests exercise performance is effected by the capactiy of the cardiovascular system. what 3 things are effected by the cardiovascular system that relate to fatigue?
oxygen delivery
oxygen utilization
metabolite accumulation
On average, humans turnover approximately how many L of fluid per day?
3L
The turnover rate of daily water on average is 3L, what are the 2 main things that effect this?
Metabolic rate and Ambient conditions
Typically we sweat _____L/hr
1-2
True or false: Typically, fluid intake does not match weat rate.
True
Typically dehydration is not greater than ___%, unless exercise duration exceeds several hours.
D) 2%
An increase in core body temperature of 0.5ºC will result in an estimated body weight loss of ___% and an increase in core body temperature of 1ºC will result in a body weight loss of ___%
a) 2, 4
b) 1, 3
b) 0.5, 2
c) 1, 2
a) 2, 4
What are the 5 characteristics that effect body fluid deficit that may cause fatigue?
1. Event duration
2. Intensity
3. Environment
4. Fluid Volume
5. Nutrient Content
Hyponatraemia and Hyperkalaermia are conditions that are both associated with long or short duration activities (not necessarily in heat)
Long duration
Sweat contains approximately _____g NaCl / L sweat in unacclimatised individuals.
B) 0.8-2.0g/L
Sweat contains approximately _____g NaCl / L sweat in acclimatised individuals.
D) 3.0-4.0g/L
Heat acclimatisation that increases sweat rate takes approximately _____ days
8-14 days
Heat acclimatisation that decreases heart rate takes approximately ____ days
3-6
Heat acclimatisation that increases extracellular fluid and plasma volume takes approximately _________ days
3-6
A decrease in rectal temperature due to acclimatisation in the heat would take approximately how many days?
5-8 days
Would urine Na+ and Cl- increase or decrease with acclimatisation, and how many days would you expect this to take?
It decreases, in approximately 3-8 days
Would sweat Na+ and Cl- increase or decrease with acclimatisation, and how many days would you expect this to take?
decreases, within 5-10 days
What are the 5 metabolic adaptions that occur after anaerobic training targeting ATP-PC system
1. MK activity
2. ATP stores
3. Adenosine triphosphase activity
4. CPK activity
5. PC stores
What is the main metabolic adaption that occurs after anaerobic training targeting anaerobic glycolytic system
An increase in PFK activity
What is a longitudinal study?
AKA training study, Follows the same individuals over time
What is a cross-sectional study?
Examining a large variety of different individuals, usually in a shorter amount of time
How does Interval training lets us do the same amount of work?
a) exercise at a higher intensity for a shorter amount of time
b) exercise at a low intensity over short duration
c) exercise at the same intensity over longer duration
d) higher intenisty work in shorter blocks of time
e) both c and d
both c and d
A certain amount of energy is needed to perfrom a quantitiy of work irrespective of whether the work is done _________ or _____________
Continuously or intermittently
Number of repetitions in a session and duration of all the work intervalls is known as the _______
Volume of work
Why is BLA especially useful during AEROBIC interval training?
Because during anaerobic training you expect it to be high anyway, so during AEROBIC interval training BLA gives an indicator of whether or not you are working above or below thresholds
BLA throughout history has been used in Australia in which sport?
Swimming
HR can alter during a training session due to _________ and __________.
1.Training intensity, or
2. dehydration /cardiovascular drift
in 30s best case scenario, PC is only _____ restored in 30sec
half
When designing an interval training program for ATP-PCr energy system, the minimum W:R ratio is 1:3 but it can extend up to...?
1:30
Approximately how much time should be given to an athlete to recover between sets when training the ATP-PCr system via interval training methods?
8-10minutes
Usually, the intensity of Lactic acid/short-term energy system interval training should be around __ -___% effort.
90-100%
Adaptions to 24months of endurance training would see the greatest rise in:
D) Krebs cycle enzymes
During the relief phase of interval training, what would you expect to happen to VO2, RPE and HR compared to the work phase of the interval training?
They would drop
If the goal for that particular interval session is to stress the lactate system: then what type of relief should you definiately NOT use and why?
low passive or higher active,
low active recovery oxidizes lactate which defeats the purpose
When adapting to chronic endurance trainging; Capillarisation, Enhanced oxidative potential of FT fibres, VO2max and cross-sectional size of Slow twitch fibres usually ________ then_______
increase then plateau
Krebs cycle enzymes increase during chronic endurance training: why is this so important?
they're incolved in re-producing ATP
after detraining for at least 6 months (even after a 24month training program) where would you expect adaptions to be at?
back at baseline
Mitochondria need to increase in size or number so they can:
fit more enzymes in!
True or false: there is a detremental size that mitochondria can get to
True; if they're too bit there is a oxidative difusion issue
Type IIB can also be known as type ___ in humans
type IIX
Myokinase (MK) is now known as :
adenosine kinase
PFK (phosphofructokinase)
key regulatory enzyme for glycolisis
The 3 Glycolytic system enzymes are:
PFK : phosphofructokinase
Phosphorylase: Glycogen Phosphorylase
LDH: Lactate dehydrogenase
The 2 main enzymes for ATP-PCr system:
Creatine Kinase and Myokinase
What are the 3 main aerobic enzymes?
succinate dehydrogenase
malate dehydrogenase (both in krebs)
carnitine oalmityl transferase (is to do with fatty enzymes)
