Exercise Rx Topic 1- Principles of Exercise Prescription

Number one (and two) cause of death for all ages?

Heart disease, cancer

Number one cause of death for 15-19 yo?

accidents

What was wrong with the Healthy People 2010 initiative?

There was no “how”, it was too general- only tried to fix existing problems, not prevent them from happening. It even led to some regression

Healthy People 2020 initiative

Clear areas of determinants (physical/social environment, genetics, etc) that affect physical well being

Goals were similar to 2010 but were more descriptive

Healthy People 2030 initiative

To promote, strengthen, and evaluate efforts to improve health and well being

Retained goals of 2020 but added even more

Created goals that were individualized to the person

Childhood obesity trends

If you’re obese as an adolescent you’re a lot more likely to become obese as an adult. If you’re obese as a kid then it’s less likely for you to be obese as an adult

How can we address childhood obesity in the US?

We can control factors while young- it’s hard to break habits once they are formed (smoking, cholesterol, exercise)

Specific solutions for childhood obesity?

Group exercise, daily PE, educate parents if child is young, mainly making fitness fun/exciting

Main takeaway from Wu et al.

Small physical intervention strategies like point of decision prompts can be just as meaningful as other strategies like large support groups if these changes are persisting over time

Main takeaway from Racette et al.

School based physical activity programs not only increase the duration of physical activity, they are also proven to change behavioral, attendance, and academic performance issues.

Two types of physical fitness outcome measures

A: Hand eye coordination, agility, speed, balance

B: Cardiorespiratory endurance, body composition, flexibility

Heart disease trends over time

There was a small decline in CVD after 1980s after advances in medicine

Prevalence of cardiovascular disease by age

Early on in life, males have much higher prevalence of cardiovascular disease

At 65-74 prevalence becomes higher in females (previous men die of heart disease)

Heart disease risk factors that can’t be changed

age, gender, genetics

Heart disease risk factors that can be changed

cholesterol, blood pressure, smoking, physical inactivity, obesity- each increase risk by 2 fold! DM and stress are lesser risk factors

Physical inactivity is more prevalent in which groups

women, African Americans/Hispanics, older adults, lower socioeconomic status

Why are there worksite exercise programs (for adults?)

Companies want their workers to be more productive

Morbidity

absence of health (difference between max QOL and min QOL)

Compression of morbidity

the process of decreasing morbidity- often through exercise, which improves QOLH

How do you improve QOL/health?

Regular physical activity (30-60 min most days of the week)

Exercise Prescription

a prescribed course of action to meet specific fitness goals- a “road map”

FITT

frequency, intensity, time, type

Physical Activity

bodily movement

Exercise

Physical activity that is planned, strutted, repetitive, and purposeful

Sport

physical activity governed by rules

Physical Fitness

attributes relating to ability to perform a physical activity

Three types of physical fitness

Aerobic, body composition, and muscular fitness (flexibility and strength)

Health vs Wellness

health- a complete physical, mental, and social well-being (a state) all three factors depend on each other

wellness- continuous, active process to work on health

Mental, physical, and social health

Mental- absence of mental disorders

Physical- absence of physical disease

Social- ability to interact effectively with people and environment

Moderate physical activity

minimum 30 min, 5x/week

RPE 5/6-10, 40-59% Vo2 Max, 3-5.9 METs

RPE

rating of perceived oxygen

Vigorous physical activity

minimum 20 min, 3x/week

60%+ Vo2 max, RPE 7/8-10, 6+ METs

Recommendations for physical activity for healthy adults

30+ min aerobic activity 5x/week

Recommendations for physical activity for kids

60+ min daily, moderate to vigorous

has to be developmentally appropriate, varied, and enjoyable)W

What do do if child is physically inactive?

Increase activity by 10% each week until you get to 60 min

MET

metabolic equivalent- a unit used to estimate the metabolic cost of physical activity

I MET=

resting metabolic rate 3.5 ml O2/kg body weight/min (VO2 max)

or- how much oxygen taken in relative to body weight over time

Levels of intensity and their METs

Light- 1.6-2.9

Moderate- 3-5.9

Vigorous- 6+

Long vs short method of calculating calories from METs

Long: convert METs to ml/O2/kg/min, multiply by time then weight, then change mL to L, and convert L Oz to kCal

Short: convert to kCal/hr (multiply the METs by weight), then convert to however many hours were spent

Three components of health related fitness

cardiorespiratory fitness, body composition, muscular fitness (strength, endurance, and flexibility)

Components of performance related fitness

Agility, balance, coordination, speed, power, reaction time

Agility

rapidly/accurately changing direction

Balance

maintaining equilibrium while stationary/in motion

Coordination

use senses together with body parts to organize complex movements

Speed

perform a movement within a short period of time

Power

rate at which you perform work (P= Fd/t)

Reaction time

time elapsed between stimulus and start of reaction

Cardiorespiratory endurance

ability of the circulatory and respiratory systems to supply oxygen during physical activity

What is cardiorespiratory endurance measured in?

VO2 max

VO2 max

maximum oxygen consumption during maximal exertion

open circuit spirometry

difference in oxygen in volume of inhaled/exhaled air

Cardiac output

CO or Q- quantity of blood pumped out of the heart every minuteC

CO =

stroke volume x heart rate (SV x HR)

As VO2 increases, cardiac output ____, and what type of relationship is this?

increases (linear relationship)

How do we measure VO2 max?

True V02 max is difficult to measure- we use submaximal exercise tests and the relationship between HR and oxygen

body composition & equation

ratio of fat mass to fat free mass

fat weight/fat free weight

percent body fat equation

fat weight/total body weight x 100

Obesity

excessive accumulation of fat

Overweight

excessive weight for height (does not consider body composition)

BMI equation

kg/m²

6 methods for measuring body composition (and their effectiveness)

1. circumference- not advisable (sometimes inappropriate)

2. skinfolds- method of choice (correlates well with underwater weighing and Dexa scans)

3. bioelectrical impedance- electric current, also good method, but important to be hydrated! (otherwise could appear to have extra fat)

4. underwater weighing

5. MRI

6. Dexa scan

4, 5, 6 are all very accurate but cost $

Muscular strength

maximal force in one contraction- measured w/ max lift or handgrip dynamometer

Muscular endurance

ability to maintain force over a series of contractions (w/o fatigue)

exs: sit ups, push ups

Flexibility

capacity of the joints to move through a full range of motion (different range for each joint in the body)

3 main factors of flexibility

bony structure of joint, amount of tissue, elasticity of the muscles/tendons/ligaments