YEAR 12 PHYSICAL EDUCATION
Course Summary
Benefits of physical activity / Barriers to participationSocial / improves social skills / Lack of time
Physical / manages weight / Injury
Mental / improves concentration / Low income
Environmental / reduces traffic / Increased use of motorised transport
Economic / reduces absenteeism / Lack of self-motivation
Health / reduces risk of CVD / Limited access to facilities
Domains of physical activity
Occupational PE teacher, fireman
Household Vacuuming
Active transport Walking to work
Leisure Netball team
National Physical Activity Guidelines
Aim: To enable everyday people to incorporate physical activity into their daily lives.
Four main adult guidelines:
1. Put together at least 30 minutes of moderate intensity physical activity on most, preferably all, days
2. Think of movement as an opportunity, not an inconvenience
3. Be active every day in as many ways as you can
4. If you can, enjoy some regular, vigorous exercise for extra health and fitness
ADULTS / CHILDREN & YOUTH / OLDER PEOPLE / OVERWEIGHT & OBESEF / Most (5), if not all days / Everyday (7) / Most (5), if not all days / Everyday (7)
I / Moderate / Mod-vig / Moderate / Low-mod
D / 30mins / 60mins / 30mins / 60mins
T / Range of activities / Range, incl wt bearing / Range w/ fitness, strength, balance / Range, incl. aerobic
Notes / Vigorous 3-4/wk @ 30mins / <2hrs electronic media/day / Once wt lost 60-90mins
Physical activity pyramid
LEVEL / ACTIVITY / FREQUENCY / INTENSITY / DURATION1 / Lifetime: stairs, walk, golf / 7 / Mod / 30+
2 / Aerobic & team sports / 3-6 / Mod-vig / 20+
3 / Flexibility & strength / Flex: 3-7
Strength: 2-3 / Flex: 15-60sec
Strength: 8-12
4 / Rest/inactivity: reading, TV / Infrequent / Low / Short
Intensity
Low / Mod / VigorousTalk test / Sing / Talking / None
Heart rate / <50% max HR / 50-70% max HR / 70-85% max HR
Perceived exertion / 6 / 20
METs / 1 / 3-6 / 6+
Measuring physical activity
Subjective
Explanation / Example / Advantages / DisadvantagesDepend on our own perceptions. Used for measuring large populations / Self report:
§ Diary
§ Log book
§ Recall / § Quick & easy
§ Cheap
§ Good for individuals or large groups (assess many domains)
§ Quantitative & qualitative / § Reliability & validity problems
§ Relies on honesty
§ Not good for kids & elderly
Objective
Explanation / Example / Advantages / DisadvantagesRely on solid data or observations. Used for individuals or teams / Heart rate
Pedometers
Accelerometers
Observation / § / §
Objective method / Advantages / Disadvantages
Heart rate telemetry / § Strong link to energy expenditure
§ Low participant burden
§ Clear in describing I, F, D
§ Quick and easy data collection / § Expensive for large numbers
§ Some discomfort
§ Restricted to aerobic activities
§ Influenced by other factors (age, stress, emotions)
Pedometers / § In-expensive
§ Small, lightweight, non-intrusive
§ Useful in a variety of settings
§ Easy to administer
§ Measures a common activity
§ Immediate feedback
§ Potential to promote behaviour change / § Assesses only walking
§ Cannot record F, I, D
§ Participant tampering
§ Potential to be reactive (participant increases activity due to being monitored)
Accelerometry / § Small, lightweight and non-invasive
§ Clear in describing F, I, D
§ Simple, quick data collection
§ Records in real time (minute by minute) / § Expensive for large groups
§ Inaccurate assessment of some activities
§ Can’t specify T of activity
Observational tools / § Excellent qualitative and quantitative data
§ Specific physical activity behaviours can be observed
§ Useful in a variety settings
§ Easily combined with software packages
§ Can collect contextual information / § Training needed for observer
§ Presence of observer may bias behaviour
§ Highly labour intensive and time consuming
Practicality v. accuracy –
Practical: easy to use, easy to use for that activity
Accurate: provides valid/correct data
Individual approaches to physical activity promotion
Self-efficacy –
Feelings of self-value or self-worth. Increases as you move through stages of change model. Active people have a higher self-efficacy.
Stages of change
Stage / Description / Possible signs1. Precontemplation / Not ready for change / No intention to be active within next 6 months
Not aware that lack of PA is a problem
Avoid info and opportunities
2. Contemplation / Thinking about change / Acknowledge that they need to become more active
Intend to become active
Weigh up pros and cons
3. Preparation / Preparing for action / Appear to be ready & committed
Plan developed - goal setting
Some small amounts of PA
4. Action / Carrying out the plan / Implementing the plan
Large amount of time, effort and energy used
Relapse common
5. Maintenance / Maintaining a good thing / Regularly active
Meeting NPAG for min of 6 months
Sets new goals
6. Termination / Maintaining regular activity for more than 5 years / 5+ years active
Everyday lifestyle
New goals and rewards important
Relapse –
Moving back to another stage is a common problem. Generally between stages 2 & 4. Reach maintenance, generally only relapse to preparation.
Print and web-based media
Example / Advantages / DisadvantagesPrint / Brochures, booklets, handouts from gyms, doctors, etc. / Free
No computer / May not read
Web / Internet, emails / Individual advice / Cost – internet, PC
Novelty wears off
Counselling
Example / Advantages / DisadvantagesHealth professionals / Doctors, PT, physios / Very effective
80% pop see GP each yr / Not enough time to discuss and implement
Cost
Telephone / Follow up call, automated message / Collect data for research
People in remote areas
No reading skills / No face-to-face contact
Hearing impairment
Novelty
1. Assessing motivational readiness
a. Questionnaire
2. Matching processes of change with motivational readiness
a. Using strategies appropriate to stage of change (motivational readiness)
b. Cognitive (attitudes, thinking) – Stages 1-2; Behavioural (action, doing) – Stages 3-6
3. Identifying opportunities to be active
a. Lunchtimes, before work
4. Contracting
a. Write down plan, sign, witness
5. Enlisting social support
a. Exercise partner
6. Reminder systems
a. Notes, text messages
7. Gradual programming
a. Progressive overload
8. Tailoring
a. Needs to be individual
b. Plan around other aspects of life
Population approaches to physical activity promotion
Policy
§ Laws, regulations, formal or informal rules, understandings
o Guide individual and collective behaviour
o Eg: 100 mins of PE/sport per week 7-10, runners at lunch time, sports equipment borrowing
§ Legislation: formal, documented, governed
o Eg: seat belt
§ Organisational policy: implemented in specific organisations
o Eg: smoke-free schools
Environmental strategies
§ Tailoring
o Align strategy with the setting
o Eg: bike rack in rural school v. urban school
§ Removing impediments to activity
o Remove heavy traffic, stranger danger
o Eg: install speed humps, 40km/h zones, Neighbourhood Watch program
§ Introducing new resources and facilities
o Eg: Gyms/showers at workplace, footpaths/bike trails, playgrounds
§ Educational programs
o Environmental programs are more effective when supported by educational programs
o Eg: benefits to work output if you exercise linked with introduction of gyms at workplaces
Mass media
§ Strategies that reach a group of people using a medium other than personal contact
§ The main benefit to the potential to advocate to large numbers of people at a low cost
§ Examples: billboards, TV ads, radio ads
§ Key roles
· Increasing awareness of physical activity as a public health issue
· Providing information on health benefits
§ Providing information about other non-health benefits
§ Providing information on the consequences of inactivity
§ Increasing interest in physical activity
§ Raising awareness of community-based programs
§ Motivating individuals to take action
Settings-based approaches to promoting physical activity
School setting
Strategy examples / Specific programs / EffectivenessCurriculum – PE & sport
Extra curricular – sport teams, camps
Free play
Facilities – gyms, playgrounds / Walking school bus
Travelsmart
Gold medal project / Whole school approach best
More likely to become active adult
Crowded curriculum a problem
Community setting
Strategy examples / Specific programs / EffectivenessLocal facilities
Use of community centres
Free health check ups
Health info sessions / PICSAR
10,000 steps
Walk and talk / Limited evidence
Best to use multiple strategies across all settings
Workplace setting
Benefits / Difficulties / Strategy examples / Specific programs / EffectivenessImproved morale
Increased work production
Decreased absenteeism / Lack of interest from m‘ment
Size of org.
Lack of facilities
Lack of support from workers / Campaigns to use stairs
Subsidised gyms
Incentives to ride/walk to work / Find 30
Stairway to health / Comprehensive approach needed
Targeting at-risk groups
Young Australians Aussie sport
Older Australians Living longer, living stronger
People w/ disabilities Willing and able
Women Women, sport and the media
Indigenous Australians Indigenous sports trust, anti-racism strategy
Ethnic groups Ethnic youth sports development program
Energy
ATP
§ Adenosine Triphosphate
§ From CHO, fat, protein
Food fuels
Food fuel / Stored as / Storage siteCHO / Glucose
Glycogen
Adipose tissue / Blood
Muscle & liver
Around the body
Fat / Free fatty acids
Triglycerides
Adipose tissue / Blood
Muscle
Around the body
Protein / Muscle
Amino acids / Skeletal muscle
Body fluids
Energy from ATP (ATP à ADP)
One of the three phosphate molecules is released to create energy for muscular contraction
Energy from ATP (ADP à ATP)
ATP must be continually rebuilt (resynthesised) so that energy can be provided for longer periods of time.
The process is reversed using PC to reattach a free phosphate molecule to make ATP again.
Energy systems
Main energy system in control depends on:
§ D
§ I
§ How urgently the energy is required
§ If oxygen is present
At rest
Oxygen available
2/3 energy comes from fat (more energy is contained in fat; fat is harder to break down; requires more oxygen)
1/3 energy comes from CHO
This is aerobic metabolism. End products are: CO2, H2O and heat.
During activity
Increased oxygen needed for muscles
Short duration and high intensity use anaerobic systems
Longer duration and low intensity use aerobic system
ATP-PC system
§ No oxygen
§ Small amount of ATP is stored in muscles
§ Maximal intensity (95%+ max HR)
§ Short duration 1-10sec
§ Once ATP is used it needs to be reproduced
§ PC is the substance used to provide the energy to reattach the free phosphate molecule to ADP
Lactic acid system
§ No oxygen
§ High intensity (85-95% max HR)
§ Short duration 10sec – 2-3min
§ ATP resynthesis comes from the breakdown of glycogen (glycolysis)
§ Because no oxygen is present glycogen cannot be completely broken down
§ Pyruvic acid is created, which is then converted to lactic acid
§ Hydrogen ions also released
§ These two by-products lead to a decrease in ATP production and an increase in fatigue
Aerobic system
§ Creates the most energy because oxygen is present
§ Slowest system
§ Sub-maximal (<85% max HR)
§ Duration >30sec
§ Stage 1
o CHO (glycogen) broken down into glucose and pyruvic acid using oxygen (glycolysis) in the mitochondria
o No LA due to oxygen
§ Stage 2
o Pyruvic acid breaks down in the Kreb’s cycle releasing ATP and CO2
§ Stage 3
o Electron transport chain also produces large amounts of ATP
o By-products are H2O and heat
Energy system interplay
§ Virtually all physical activities receive energy from each of the three energy systems
§ Each system is best suited to supplying energy for specific types of events or activities
§ They overlap each other depending on the type of activity and exercise demands
§ They do not turn themselves on and off
§ What does differ is the relative contribution and importance of each system to rebuilding ATP and supplying energy
Onset of Blood Lactate Accumulation (OBLA)
When exercising the levels of lactate and hydrogen ions rise.
Lactate Inflection Point (LIP)
§ Lactic acid production is greater than lactic acid removal
§ At exercise intensities beyond the LIP blood lactic acid concentration increases
§ Beyond the LIP the athlete has to stop or reduce muscular effort
§ Lactic acid has some positive effect on performance because it can be broken down into pyruvic acid then ATP through the Kreb’s cycle, thus producing more energy with oxygen
Conversion of food to energy
Glycemic Index (GI)
§ Ranking of CHO according to how quickly they are digested and release energy
§ High GI foods are broken down quickly releasing energy quickly
§ Appropriate for post strenuous exercise to replenish glycogen stores
§ Low GI foods are broken down slowly releasing energy slowly
§ Appropriate for pre-event meals for sustained energy during the event
Fat
§ Provides FFA that provide energy
§ Provides more energy than CHO, but requires more oxygen because it is harder to break down
§ Contributes to taste, texture and aroma of food
§ Provides protection for certain organs
§ Recommended amount is 20-30% of sporting diet
§ Becomes vital if CHO are depleted during exercise
§ Glycogen sparing: Through aerobic training athletes can teach their bodies to use fats first in long events to keep glycogen stores in reserve for the high intensity part of the event
Protein
§ Makes up about 15% of the diet
§ Important in growth and repair of body tissues
§ Is an emergency fuel in the rare occurrence that all CHO and fat is depleted
§ Some athlete’s performing in endurance or power activities ingest extra protein; this is generally not required as a sufficient diet has ample protein
Vitamins
§ Assist chemical reactions in the body
§ Fat soluble: stored in the body
§ Water soluble: not stored in the body