Exercise perscription/physiology Flashcards
What is ‘public health’?
The art and science of preventing disease, prolonging life and promoting health through organised efforts of society (Acheson, WHO, 1988).
What physical activity does the CMO reccomend for adults aged 19-64?
Any activity is better thannone.
Do activities to develop or maintain strength of major musclegroups.
Accumulate 150 minutes of moderate activity OR
75 minutes of vigorous activity.
What physical activity does CMO reccomend for adults over 65?
Participate in daily physical activity.
Improve or maintain muscle strength, balance and flexibility twice a week.
Accumulate 150 minutes of moderate activity OR 75 minutes vigorous.
Break up prolonged periods of sedentary behaviour.
What is the ICF?
The International Classification of Functioning, Disability and Health (ICF) is a framework for describing and organising information on functioning and disability. It provides a standard language and a conceptual basis for the definition and measurement of health and disability
Define ‘body functions’
The physiological functions of body systems (including psychological functions).
Define ‘body structures’
Anatomical parts of the body such as organs, limbs and their components.
Define ‘impairments’
Problems in body function and structure such as significant deviation or loss.
Define ‘activity’
The execution of a task or action by an individual.
Define ‘participation’
Involvement in a life situation.
Define ‘activity limitation’
Difficulties an individual may have in executing activities.
Define ‘participation restrictions’
Problems an individual may experience in involvement in life situations.
Define ‘environmental factors’
The physical, social and attitudinal environment in which people live and conduct their lives. These are either barriers to or facilitators of the person’s functioning.
Define ‘functioning’
Functioning is an umbrella term for body function, body structures, activities and participation.
It denotes the positive or neutral aspects of the interaction between a person’s health condition(s) and that individual’s contextual factors (environmental and personal factors).
Define ‘disability’
Disability is an umbrella term for impairments, activity limitations and participation restrictions.
It denotes the negative aspects of the interaction between a person’s health condition(s) and that individual’s contextual factors (environmental and personal factors).
Give the 4 ICF components
- Body functions and structures of people, and impairments thereof (functioning at the level of the body)
- Activities of people (functioning at the level of the individual) and the activity limitations they experience;
- Participation or involvement of people in all areas of life, and the participation restrictions they experience (functioning of a person as a member of society); and
- Environmental factors which affect these experiences (and whether these factors are facilitators or barriers).
Define ‘physical activity’
Body movement that uses skeletal muscles and results in an increase in calories required. This should be over and above the resting energy expenditure.
Define ‘exercise’
A type of physical exercise but is planned and includes repetitive movements to improve or maintain components of physical fitness (ACSM, 2016).
Define ‘phsyical fitness’
The ability to meet the planned and unplanned tasks in day-to-day life. These should be undertaken with ‘vigor and alertness’ (ACSM, 2016).
List the key components of physical fitness
- Cardiovascular Endurance
- Strength
- Muscular Endurance
- Flexibility
- Balance
- Power
- Speed
- Reaction Time
- Agility
- Coordination
Give the benefits of physical activity/exercise
-Improved CV and respiratory function
-Reduced CVD risk factors
-Decreased all cause morbidity and mortality
-Reduced depression and anxiety
-Improved cognitive function
Briefly explain exercise physiology in terms of ATP production
- Exercise demands oxygen and a substrate are increased.
- Chemical, mechanical and thermal stimuli affect alterations in function.
- The body firstly uses immediately energy sources that include ATP.
- Alternatively, utilisation of the Adenylate Kinase Reaction as well as the Phosphocreatine system are important.
- Resynthesis of ATP from energy-dense substrates via Glycolysis and fat metabolism.
What are the FITT principles?
Frequency
Intensity
Time
Type
…of each exercise
List the key aerobic principles
- Specificity
- Progressive Overload
- Reversibility (use it or lose it)
- The Individual / Variability
Give examples of exercises
Pendular exercises
Stretching
Active Assisted exercises
Sit-to-Stand
Isometric exercises
Describe the power stroke of muscle contraction and why ATP is an important energy storage molecule
- Actin-myosin cross-bridge cycling
- ATP-energised myosin head attaches to the exposed actin binding site
- Power-stroke occurs as one Phosphate ion dissociates (ATP => ADP + Pi)
- ADP dissociates from the cross-bridge but the actin-myosin link remains intact
- New ATP releases the myosin head from actin site & cycle starts again
- ATP is essential part of muscle contraction
- Continued muscle contraction requires continual supply of ATP
Chemical energy is contained within the high-energy phosphate bond and it is converted to mechanical energy during the power-stroke.
Some ATP also required by the Ca2+ pump to pump calcium back into the sarcoplasmic reticulum against the concentration gradient during muscle relaxation.
Why is muscle contraction required even at rest
Maintaining tone, postural muscles
Why is little ATP stored in muscles
Significant amount of ATP not stored in muscle due to the volume required (which would make the weight prohibitive). For example, to run a half marathon, 90kg of ATP would be required.
Therefore, only very few ATP molecules are stored within the muscle, instead rapidly and continuously synthesysed.
What is phosphocreatine?
- Stored locally in the muscle
- Very fast & powerful but short-lived system
- Initial 2-10s of exercise
Briefly outline anaerobic glycolysis
- Degradation of glucose to pyruvate
- Quite fast & powerful, 10s-2mins
- During onset of exercise or high intensity exercise, pyruvate is converted to lactate (anaerobic pathway)
Glycolysis can use glucose or glycogen. Glycogen stores are greater in Type 2 (fast) muscle fibres.
Anaerobically, pyruvate is converted to either ethanol or lactate, so isn’t available for the Krebs cycle. Therefore anaerobic respiration doesn’t involve either the Krebs cycle or the electron transfer chain. The ATP that can be produced by anaerobic respiration is therefore formed by glycolysis only.
Describe aerobic ATP synthesis
- Occurs exclusively in the mitochondria
- Can metabolise carbohydrates, lipids or proteins
- Primary energy source during sustained, moderate activity
- Oxygen is the final electron acceptor in the electron transport chain
- Most efficient & sustainable system
- Slowest system
- Reliant on oxygen delivery to the cells
- Very minimal energy from proteins under normal exercise circumstances.
Why is oxygen important to respiration
Oxygen is the final acceptor of electrons and hydrogen ions/protons in the electron transfer chain. Without it the electrons would accumulate along the chain and respiration would cease. Neither the Krebs cycle nor electron transfer chain can continue because soon all the NAD and FAD will be reduced. No NAD or FAD will be available to take up the H+ produced during the Krebs cycle and so the enzymes stop working. This leaves only the anaerobic process of glycolysis to produce ATP.
In an indvidual exercises for longer than 2 minutes what type of respiration is undertaken?
Aerobic
Describe the relationship between workload and oxygen uptake
As the workload increases, the oxygen uptake by the tissues increases (hence the delivery of oxygen to the tissues needs to increase).
Describe the relationship between workload and carbon dioxide production
The production of C02 also increases with work rate (hence the removal of C02 from the tissues needs to increase).
Define VO2max
Point at which no further increase in oxygen consumption can occur despite further increases in work performed
Define anaerobic threshold
The addition of anaerobic glycolysis to ATP resynthesis increases CO2 Production
Define oxygen debt
Oxygen uptake during recovery
At the onset of exercise, there will be a “lag” in oxygen delivery. This combined with any other anaerobic work done during exercise (particularly during high intensity exercise) is “repaid” during the recovery period. This is why breathing and heart rate remain elevated after exercise stops.
