Week 1 - Physical Activity Basics

What is Physical Activity?

any bodily movement produced by skeletal muscles that results in energy expenditure

- Totalitly

(Requirement for ATP)

How much Physical Activity do we need?

•150 minutes of Moderate-to-vigorous physical activity (MVPA)

•2 days a week should include muscle-strengthening/ resistance exercises

What are the 24hr movement guidelines for 5 to 17?

- Sweat (moderate to vigorous physical activity)

- Step (light physical activity)

- Sleep (9 - 11 hours)

- Sit (no more than 2 hours per day of recreational screen time)

What are the 24hr movement guidelines for 18 - 64 years old?

•150 minutes of Moderate-to-vigorous physical activity (MVPA)

•2 days a week should include muscle-strengthening/ resistance exercises

• Several hours of light physical activities + standing

• 7 to 9 hours of sleep

• Less than 8 hours of screen time (no more than 3 hours recreational)

What is Exercise?

Physical activity that is planned, structured and repetitive exercise to enhance one or more components of fitness (strength, endurance, agility, etc)

What is physical fitness and what does it mean?

Ability to carry out tasks with vigour and alertness without undue fatigue and ample energy to enjoy any leisure time activities, as well as to rise to meet unforeseen emergencies

What are the two components of physical fitness?

health-related and skill-related

What are five examples of health-related fitness?

• Cardiovascular endurance

•. Muscular Endurance

• Muscular strentth

• Body compostion

• Flexibility

What are six skill-related fitness examples?

• Agility

• Balance

• Coordination

• Speed

• Power

• Reaction time

How do we achieve physical fitness?

Exercise is key with the help of proper nutrition

- OVERLOAD

What does FITT stand for?

• Frequency ( how many times a wk)

• Intensity (% of vo2Max)

• Time (mins of overload)

• Type (Resistance, strength, etc)

What is the intensity of moderate PA?

• Any activity that causes you to sweat a little and to breathe harder

• RPE : 5 to 6

• % VO2Max 50 - 70%

What is the intensity of Vigorous PA?

• Any activity that causes you to sweat a lot and be "out of breath"

• RPE : 7 or 8

• % VO2Max: 85%

What is a VO2 Max test?

• Ventilation increases in a linear manner from 50-75% VO2max

• Then rises exponentially - ventilation threshold (also, point of lactate threshold)

• At this point, your ability to voluntary talk is overridden by your muscles need for oxygen (and removal of CO2)

• ~85% VO2max

What are some health and physiological benefits of PA?

• Mobility

• Self-confidence

• Sleep

• Fitness

• Mental Health

• Social component

• Aging/ longevity

• Energetic

What are the effects of being active on oxygen consumption?

Being active increases oxygen consumption

- Resting: 250 ml/min

- Untrained male: 3600 ml/min

- Trained male: 4000 ml/min

What are the two goals of respiration?

- To provide oxygen to tissues

- To remove CO2 from tissues

What are the 4 major events of respiration?

- Pulmonary ventilation or the exchange of O2 and CO2

between the atmosphere and the lungs

- Diffusion of O2 and CO2 between lungs and blood

- Transport of O2 and CO2 in the blood to tissues

- Regulation of ventilation

What is the end result of the CV after exercise?

The end result of CV function during exercise is to

deliver O2 and other nutrients (e.g., glucose, amino

acids) to the muscle

- Muscle blood flow increases drastically during exercise

- Resting: 3.6 ml/100 g muscle/min

- Max exercise: 90 ml/100 g muscle/min

Other than the muscles themselves, why is there an increase in the CV system function?

This increase is caused not only by factors in the

muscles themselves, but to an increase in mean arterial

pressure

What is arterial pressure?

This increases the force by which blood is pushed through the vessels and distends the vessels to decrease resistance

What do we see during exercise on the CV system?

- ↑ muscle work output = O2 consumption↑

- ↑ O2 consumption = dilation of vessels

- ↑ venous return = cardiac outpu

What are the adaptations of the CV system with training?

- Potential increases in heart muscle mass

- Resting cardiac output remains similar to a normal person,

however..

- ↑ stoke volume at a heart rate↓

- More blood pumped out of the heart per beat

-Resting heart rate is lower

- Bottom line: heart works less

What are the metabolic health benefits of exercise?

- Improved insulin sensitivity

- Improved blood pressure

- Imporoved blood lipids

How does exercise improve insulin sensitivity?

- Exercise increases sensitivity of glucose uptake to insulin in human muscle

- This reduction in insulin concentration elicits half the maximum glucose uptake response

- This means that there is a leftward shift, where there is less insluin needed to clear glucose

Due to:

Increases in insulin signalling intermediates

Increases in GLUT 4 protein

May require an intensity of 70% VO2max or more

What are GLUT4 proteins?

- There is an increase in this protein with exercise

- Their effects are very transient, so exercise must be done repeatedly and consistently

- This protein is stimulated by insulin and exercise

For the improvement in glucose, when is the best time to exercise?

To have the best impact on type 2 diabetes, you need to capitalize on exercise post-meal as the GLUT 4 pathway is targeted, and this will lower blood glucose

How does exercise improve blood pressure?

- Occurs acutely and at lower intensities (40% VO2max)

- Systolic is the resistance, which is more important, as we want a response with dilation

How does exercise improve blood lipids?

There isnt alot that exericse can do for the lipids as diet is more important

- Increases in HDL = the garabage men proteins that clear watse

- Decreases in TG

- Decreases in LDL but only after prolonged exercis

What is the formula for total energy expenditure?

BMR/RMR + DIT + AEE

What is resting metabolic rate (RMR)?

- Makes up about 60-75% of TEE

- The amount of energy required at rest to maintain body temperature and involuntary muscle

contractions (e.g., ventilation)

- BMR + arousal/wakening

- Affected by age, gender, body composition, body siz

What is diet-induced thermogenesis?

Makes up about 10% of TEE

What is activity energy expenditure?

Makes up 20-30% of TEE

What is excessive post-exercise oxygen consumption?

- After exercise, you see different things in the body occur, like muscle repair, lactate rebalancing, ATP and creatine rebalance, temperature regulation (sweating more after activty) and CV system (increase heart rate)

What does intensity have to do with the effects of EPOC?

This benefit will not happen unless you exercise at 60 - 70% of VO2max

- The higher the intensity means longer EPOC

What are the contributions to EPOC Rapid, short phase (lasts 1 hr)?

- Replenishment of oxygen in blood and muscles

- ATP/P-creatine synthesis

- Lactate removal

- Body temperature regulation

- Ventilation and respiration regulation

What contributes to EPOC in the prolonged phase?

- Re-esterification of FA

- Protein resynthesis

what are the results of RMR vs. EPOC?

RT: The increase in RMR is attributed to an increase in FFM

RT + Aerobic: Decrease in RMR (adaptive thermogenesis, where the body is more resistant to changes)

What is said about PA and weight loss?

- Weight loss is a challenge to maintain

- The main goal of PA is not weight loss it is more about body recomposition

- We may see a little bit of extra weight with aerobic training (tends to be more sustained, and you burn more calories

- A combo of diet and exercise has the greatest weight loss and fat loss

- Aerobic > resistance

Why do we not go under 1200 calories?

= you do not want to put a person in a malnourished state

= you need to make sure they are getting enough energy to do the activities they need to do throughout the day