Foundations of Exercise & Sport Science Flashcards
List the major families of sensory receptors
- Mechanoreceptors (physical force)
- Thermorecpetors (temperature)
- Nociceptors (pain)
- Photoreceptors (light)
- Chemoreceptors (chemical stimuli)
What is the role of the afferent nerves?
To transmit information from the periphery to the brain
What is the role of the efferent nerves?
To transmit information from the brain to the periphery
Efferent nerves are divided into which two categories?
Autonomic & Somatic
What is the role of the autonomic system?
It regulates visceral activity within the body
What is the role of the somatic system?
It stimulates skeletal activity
The autonomic system can again be divided into which two categories?
Parasympathetic & sympathetic
List the 3 major regions of a neuron
- Cell body
- Dendrites
- Axon
Define gross energy expenditure
The total energy cost to perform an activity
What does MET stand for?
Metabolic equivalent
Define MET
A measure of the level of energy needed to complete a task
Define force
Any interaction that, when unopposed, will change the motion of an object
Define work
The product of force and distance
How can energy expenditure be measured in humans?
Equations that take into account activity levels, intensity of activity and inherent body factors
Or calculating calorimerty
BMR & RMR are affected by what factors?
- Body size
- Age
- Stress/ Hormones
- Muscle mass
- Health status
- Body temp
Define Basil Metabolic rate (BMR)
The minimum level of energy needed to sustain vital functions in the wake state
1 MET =
3.5 ml/kg/min
What percentage range represents how mechanically efficient humans are?
18-26%
Explain the influence exercise duration and intensity have on energy systems
As intensity of exercise increases, the source of energy, therefore energy system shifts from ATP to muscle glycogen to oxygen
What factors and at what rates influence daily energy expenditure?
Resting metabolic rate (60-75%)
Thermogenic effects of food (10%)
Energy expenditure during and after physical activity (15-30%)
Define power
How much work is done per unit of time
Define bioenergenics
The flow and exchange of energy within a living system
List forms of kinetic energy
- Mechanical
- Thermal
- Electrical
- Radient
- Sound
List forms of potential energy
- Gravitaional
- Nuclear
- Elastic
- Chemical
Define chemical energy
Energy stored in the bonds of atoms and molecules
Define nuclear energy
Energy stored in an atoms nuceli
Define gravitational energy
Energy stored in an objects height
Explain net efficiency
The percentage of how mechanically efficient something is.
How is net efficiency calculated?
Through a ratio of muscle power & metabolic energy expenditure
Define kinetic energy
The energy produced by movement
What enzyme catalyses the breakdown of ATP?
Adenosine Triphosphatase
Define energy
The ability to do work
What type of relationship does energy and work have?
Linear relationship
What factors influence enzyme kinetics?
pH and temperature
Explain the concept of energy
Energy cannot be created or destroyed, rather transferred from one form to another without being depleated
How is energy stored within the body?
Energy is stored in the macro nutrients as potential energy
How is energy released in the body?
Energy is released when ATP phosphates are broken
Define elastic energy
Energy stored in elastic objects
What makes up the total energy of a system?
Potential energy + kinetic energy
How much energy is expended per litre of O2?
5 kcal
How long does it take for VO2 to reach a steady state?
2-3 minutes
What does VO2 measure?
The volume of inspired and expired air per minute
Define net energy expenditure
The true energy expenditure of an activity
What does mechanical efficiency refer to?
The percentage of total chemical energy expended that contributes to external work
Economy of movement is influenced by what factors?
- Physical fitness levels
- Type of activity
- Environmental conditions
Mechanical efficiency for humans averages what percentage?
20-25%
What factors affect energy expenditure during walking?
- Body mass
- Age
- Terrain
- Downhill walking
- Footwear
Why is walking on sand harder?
Because there is more energy distribution on contact with the surface, therefore less transfer of energy back up
List 3 ways in which running speed can be increased
- Increasing stride length
- Increasing stride frequency
- Increasing both
The effect of air resistance on energy expenditure varies with what?
- Air density
- Runners projected surface area
- Square of running velocity
Energy expenditure during swimming is up to how much more/less than running the same distance?
4 times more
Define exercise efficiency
Energy required to maintain a constant velocity of movement
List the influencing factors to energy expenditure during swimming
- Fluid medium
- Temperature
- Shape, size & sex
- Swimsuit variations
- Velocity
List the structure of a research article
- Preliminary information
- Introduction
- Methods
- Results
- Discussion
- References
- Appendix
What is being measured by direct calorimetry?
Heat production
What is a P-value?
The probability of an observed result that a null hypothesis is true
Define nominal data
Data classified by some aspect or property, for which there is no hierarchy of scores
Define ordinal data
It has the ability to rank order without commenting on unit of measurement
Define interval data
Data that has known and equal distances between score units. It does not have a random zero point
Define ratio data
Similar to interval data, but does have a true zero point
Define standard deviation
The amount that all the scores differ from the mean
What is variance?
The square of the standard deviation
Define Mean
The sum of the scores divided by the number of scores
Define mode
The most frequently appearing number
Define median
The middle score
What is the purpose of inferential statistics?
To evaluate the null hypothesis at a specified level of significance
How is inferential statistics used?
By testing the influence of an independent variable on a dependent variable
What are T-tests used for?
Comparing the means of two data sets
What is the function of the cell body?
It is responsible for neural impulse development
What is the function of dendrites?
They receive neural impulses and send them towards the cell body
What is the function of axons?
They send the neural impulses
What is the function of a neuron?
They use electrical signals for communication within the nervous system in response to stimuli
List the structure of a skeletal muscle
Epimysium Perimysium Endomysium Sarcolemma Satellite cells Sarcoplasm Transverse tubules Sarcoplasmic reticulum Myofibrils Sarcomeres
What factors influence muscle architecture?
- Fascicle arrangement
- Fiber type
- Direction of fibers
What are the two basic formations of muscle?
- Fusiform
- Pennate
What factors influence muscle contraction and force production?
- Type of muscle contraction (dynamic/static)
- No. motor units/muscle size
- Frequency of motor unit stimulation
- Length-tension relationship
- Speed of contraction
What are the main circulatory elements of the heart?
- The pump (heart)
- Channels (blood vessels)
- Fluid medium (blood)
How much blood does the heart pump each beat?
55-80ml
What is the function of the right and left atria?
They are the receiving chambers
What is the function of the right and left ventricles?
They are the pumping chambers
The right side of the heart receives blood from? And sends it to?
The body, the lungs
The left side of the heart receives blood from? And send blood to?
The lung, the body
Explain the relationship between blood pressure and blood flow
Restricted blood flow has the ability to increase blood pressure, making the heart work harder
What does cardiac output reflect?
The functional capacity of the cardiovascular system by measuring the amount of blood pumped by the heart each minute
Define stroke volume (SV)
The volume of blood pumped per heart contraction
How does cardiac output respond to exercise?
During steady state exercise it will increase then plateau when blood supply meets metabolic demands
How does stroke volume respond to exercise?
It increases by 40-60% with work intensity
External ventilation refers to?
- Pulmonary ventilation
- Pulmonary diffusion
Internal ventilation refers to?
- Transport via blood
- Capillary diffusion
Define pulmonary ventilation
The exchanging of ambient air with air in the lungs
Define pulmonary diffusion
Diffusion of gases that occurs at the aveoli
What factors influence pulmonary diffusion?
- Tissue surface area
- A diffusion constant
- Pressure differential of the gas on each side of the membrane
List basic spirometry measures
- Tidal volume
- Vital capacity
- Residual volume
- Total lung capacity
Define tidal volume
The amount of air entering and leaving the lungs with each normal breath
Define vital capacity
The greatest amount of air that can be expired after maximal inspiration
Define residual capacity
The volume of air remaining in the lungs after normal expiration
Define residual volume
The volume of air remaining in the lungs after maximal expiration
Define total lung capacity
The sum of the vital capacity and residual volume
What factors influence ventilation?
- Maximum forced vital capacity
- Breathing rate
- Airway obstruction
- Pulmonary airflow capacity
What intrinsic mechanisms regulate the heart?
Sinoatrial (SA) node
Atrioventricular (AV) node
AV bundle
Purkinje fibers
What is the function of the SA node?
Initiates contraction signal
What is the function of the AV node?
Delays, relays signal to ventricles
What is the function of the AV bundle?
Relays signal to RV, LV
What is the function of the Purkinje fibers?
Sends signal into RV, LV
What is the function of an ECG?
Reflects electrical activity across the heart during a cardiac cycle
What methods are used to analyse the cardiac cycle?
ECG, 3 lead or 12 lead
What extrinsic mechanisms regulate the heart?
The autonomic nervous system