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 recommendations for physcial activity

PHAC facts

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 definitionsPhysical 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!

http://www.merthyr.gov.uk/NeedsAssessment/Health+and+Well-being/Physical+Activity.htm

Physical Activity

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• 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 zoneIn each session you should be working for 20-60

minutes and at 60-90 % of maximum heart rateMaximum HR (MHR)= 220 – your age in years = MHRMHR X 0.6 = 60% of your MHRMHR X 0.9 = 90% of your MHR

To actually determine your heart rate, measure it at your pulseIn 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

– 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 exercisingif 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• 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