Transcript Unit 7: Physical Activity

Unit 7: Physical Activity
The Average Canadian?
Physical Activity in Canada
• 63% of Candaians not getting enough physical
activity to reap the associated health benefits
• Most Candians are confused as to the PHAC facts
recommendations for physcial activity
Canadian Health Measures Survey
(CHMS,2009)
Change in PA of adults between 1981-2007/2009
Canadian Health Measures Survey
(CHMS,2009)
Change in PA of children between 1981-2007/2009
Canadian Physical Activity Guide
• Joint effort of Public Health Agency of Canada
and Canadian society of Exercise Physiologists
Key definitions
Physical Activity: any active movement you do that spends calories
Exercise: is a planned, structured and repetitive activity aimed at
improving physical fitness
• Physical fitness: how able you are to perform physically demanding tasks
The difference is your intentions!
Physical Activity
http://www.merthyr.gov.uk/NeedsAssessment/Health+and+Wellbeing/Physical+Activity.htm
Components of physical fitness
• Health related fitness: has four components
– Cardiorespiratory fitness
– Muscular strength and endurance
– Flexibility
– Body weight and composition
Components of physical fitness
• Performance-related fitness: includes
the same as health-related PLUS:
–Speed and power
–Agility
–Balance
–Reaction time
–Anaerobic power and capacity
Aerobic vs. Anaerobic Activity
• There are two main ways that your body
produces energy:
– Aerobically (with oxygen):
• C6 H12O6 + 6O2 → 6H2O + 6CO2 + 38 ATP
• Glucose + oxygen → water + carbon dioxide + ENERGY
– Or Anaerobically (without oxygen)
• C6H12O6 → 2C3H6O3 + 2 ATP
• Glucose → Lactic Acid + ENERGY
Aerobic fitness
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Uses aerobic metabolism
Activities that train the cardiorespiratory system.
Improves oxygen consumption in the body
Performed at moderate intensities for extended
periods of time
– So your cardiovascular system knows exactly how
much oxygen it needs to send and where to send it!
• Raises heart rate, breathing rate, metabolic rate
and body temperature
Recommended training zone
 In each session you should be working for 20-60
minutes and at 60-90 % of maximum heart rate
 Maximum HR (MHR)= 220 – your age in years = MHR
 MHR X 0.6 = 60% of your MHR
 MHR X 0.9 = 90% of your MHR
 To actually determine your heart rate, measure it
at your pulse
 In a ten second interval, count the number of beats
(start counting at one). Multiply that number by 6
Anaerobic Fitness
• Use anaerobic metabolism
• Intense activity that often improves strength
power, speed, and muscle mass
• These pathways are typically recruited
– in the first 120 seconds of exercise
– when exercise demand is increased
– during short bouts of intense exercise
Risks of Physical Activity
• Most common risk = injuries
– Most often effect the musculoskeletal system
– Traumatic injuries ex. Sprained ankle, fractured arm
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Overuse injuries ex. Runner’s knee, tennis elbow
General Overstress
Temperature injury
Dehydration
Sudden death
 *****In people who are already at high risk********
Risks of Exercise
• ***Overall, exercise reduces CVD risk.
However, vigorous exercise increases risk
of a myocardial infarction in people who
already have CVD
Determining if you are overtraining
• Exercise can become a compulsion: “I have to do
it no matter what!”
• Overtraining signs include:
– Persistent pain, especially of the joints
– Increased difficulty performing a standard exercise
level
– Increases susceptibility to infections. Ie. Influenza,
acne
– Feeling tired, lacking energy, lack of enthusiasm
• If you are experiencing these signs: REST!!!!
Where to start??
Have a doctor examine you before you begin exercising
if you are over 35 or at high risk
Have someone who specializes in exercise supervise
you
–Increase activity level GRADUALLY!!
Muscular Strength and Endurance
• Strength: the ability to produce a large
amount of force in a single contraction
• Endurance: the ability to perform many
repetitions with a sub-maximal resistance
Muscular Strength and Endurance:
Recommendations
• balance both sides of your body
• Do at least one exercise for each major muscle
group
• Do complimentary exercises
– Ex. biceps curls after triceps extensions
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Do a full range of motion
Work larger muscles first before smaller muscles
Maintain correct technique
Breathe!
Muscular Strength and Endurance:
Recommendations
• Overall, no single well-planned program is
superior to another
• Basic recommendation:
– Moderate intensity resistance training
– One set of 8-12 exercises done at least 2 times
per week
– Schedule at least one day of rest between working
the same muscle group
– Mix it up to avoid boredom and plateaus!
Flexibility
• Flexibility: the range of motion of a joint
– Improves lifelong mobility, reduces risk of injury
• Stretching is done to improve flexibility
– Simplest stretching = static stretching
• Muscles should be warm
• Ease into the stretch (it should never hurt!)
• Hold for at least 30-60 seconds
Flexibility
• Warming up should be done before
performing any taxing exercise
– Decreases risk of injury
• This helps your body leave its homeostatic
state and prepare itself for exercise
• Then, gently stretch the muscle
– Work your way through most joints
Yoga
• Ancient practice, with many different manifestations
• Has 8 main aspects:
• breathing, postures, meditation, control of the senses,
concentration, personal ethics, universal ethics and bliss
• Several studies support the association between
certain yoga practices and improved health
How does yoga produce health
benefits?
• Yoga downregulates the :
– Hypothalamic-Pituitary-Adrenal (HPA) axis which
leads to the release of cortisol, a stress hormone
– Sympathetic nervous system (SNS), also elevated
during stress response
• These two systems are associated with increased risk of
cardiovascular disease, obesity, diabetes, autoimmune
disorders, depression, substance abuse, thus, yoga
reduces their risk!
Meta-analysis of Yoga vs. Exercise