Physical Activity Epidemiology

Epidemic: Anything that affects a large number of people; study patterns of disease, risk  factors and causes

Epidemiology: Study of epidemics; dealing with the incidence, distribution and control of a  disease in a population

Epidemic of Physical Inactivity

  • Physical inactivity and poor diet  o Responsible for at least 16  of deaths each year in the United States,  according to CDC  Center for Disease Control
  • Two of the leading causes of diseases such as cardiovascular disease, type 2 diabetes, and some cancers
  • Industrial Revolution-Information Age  o Increased technology
  • Reduced occupational physical activity o Increased stress

 

Healthy People 2020

  •    US Department of Health and Human Services task force
  •    Builds upon Healthy People 2010
  •    Created specific objectives for US physical activity by 2020
  •    Goal: Improved health, fitness, and quality of life of US population through daily  physical activity  basically identical goals to People 2010, meaning that those goals  were not achieved

 

Examples of Healthy People 2010 Physical Activity and Fitness Objectives:

  •     Reduce the proportion of adults who engage in no leisure-time physical activity
  •    Increase the proportion of adolescents who engage in moderate physical activity for  at least 30 mi, 5 times a week.
  •    Reverse trend in school curriculum. Increase the proportion of nation’s public and  private schools that require daily physical education for all students
  •    Increase the proportion of worksites offering employer-sponsored activity and  fitness programs
  •    Increase the proportion of trips made by walking and bicycling

 

Measurement of Physical Activity Behavior

  •     Self report-survey  subjective measures  
  • Questionnaire or interview o Daily activity log  but more time consuming   o Physical activity recall  ex: Godin Leisure Time Exercise Questionnaire    o Used for larger sample sizes
  • Objective-Technological Devices  objective measures   o Heart rate monitor  o Pedometer  o Accelerometer
  • GPS
  • Used for smaller sample sizes, but data is much more accurate

    Observation

  • Direct or Indirect o Ex: Class attendance

  

Epidemiology of Physical Inactivity  The 5 W’s

Who: To what extent are individuals within a particular society physically active?

Where: Where are people most likely to engage in physical activity?

When: What variables exist in physical activity patterns across groups of individuals?

Why: Why are certain individuals physically active while others are not?  What: In what physical activities are people most engaged?

 

Canadian Physical Activity Guidelines

For children 5-11 years:

  • For health benefits, children aged 5-11 years old should accumulate at least 60  minutes of moderate to vigorous intensity physical activity daily. This should  include:  o Vigorous-intensity activities at least 3 days per week  o Activities that strengthen muscles and bone at least 3 days per week  o More daily physical activity provides greater health benefits  For youth 12-17 years:
  • For health benefits, youth ages 12-17 years should accumulate at least 60 minutes of  moderate to vigorous intensity physical activity daily. This should include:  o Vigorous- intensity activities at least 3 days per week  o Activities that strengthen muscles and bone at least 3 days per week  o More daily physical activity provides greater health benefits

For adults 18-64 years:

  •    To achieve health benefits, adult’s ages 18-64 years should accumulate at least 150  minutes of moderate to vigorous intensity aerobic physical activity per week, in  bouts of 10 minutes or more. It is also beneficial to add muscle and bone  strengthening activities using major muscle groups at least 2 days per week. More  physical activity provides greater health benefits

For older adults 65 years and older:

  •    To achieve health benefits, adults ages 65 years and older should accumulate at least  150 minutes of moderate to vigorous intensity aerobic physical activity per week, in  bouts of 10 minutes or more. It is also beneficial to add muscle and bone  strengthening activities using major muscle groups at least 2 days per week. Those  with poor mobility should perform physical activities to enhance balance and  prevent falling. More physical activity provides greater health benefits

 

Physical Activity Participation Around the World

Countries studied: Australia, Canada, England, Scotland, United States

Demographics Studied: Age, gender, ethnicity, socioeconomic status, education, level

 

Sedentary Lifestyles Across the Globe

  •     In general 50-70  of adults in countries studied do not meet recommendations
  •    Percentage of sedentary adults in each country:
  •      Australia: 15
  •      United States: 40
  •      Brazil 87

Note:+In Canada there has been a positive trend in levels of moderate PA, from 40  in 1997  to 49  in 2005

 

Age and Physical Activity

  •     Increased age means decreased physical activity
  •    Sample data:
  • In Australia, sedentary rates triple, from 6.3 for 18-29 year olds to 18   for 60-75 year olds
  • In Canada, children 1-4 spend approx. 28 hours per week being physically active, while teenagers 13-17 spend half that time
  •     Childhood PA patterns are NOT related to adult PA levels
  •    Challenge is to determine how to transfer children’s enjoyment of sports-play  into lifetime physical activities
  •    Older adults particularly at risk of being sedentary. English adults 75+ years: less  than 20  engage in medium or high levels of physical activity

 

Gender and Physical Activity

  •     Men have historically been more physically active then women
  •    Canada: 54  male, 45  female moderately active  i.e., at least 30 min of  moderate-to-vigorous physical activity daily
  •    Men are more likely to engage in vigorous activities, while women engage in  more moderate-intensity activity

 

Ethnicity and Physical Activity

Data available only for USA:

  •     Caucasians tend to be more physically active than other ethnic groups
  •    Caucasians tend to engage in more vigorous physical activity than other groups
  •    Hispanic and African Americans are the lowest
  •    Fewer Caucasian high school students  27   watch TV for more than two hours  compared to Hispanic  43   and African American  63   students
  •    A greater proportion of Hispanic children  36   participate in daily PE at school  than other groups  29  Caucasians, 32  African Americans , but not sure why

 

Socioeconomic Status and Physical Activity

  •    Although the relationship between income level and physical activity  participation has typically been viewed as a relatively direct and linear one, this  finding is not consistent across countries
  •    This relationship holds best for Canadian and Brazilian adults
  • PA rates in Australian adults:  o 65  with highest incomes engaging in sufficient PA, but only 30  with  lowest incomes

o When considering adults who are active at insufficient levels, no  difference is observed with income

 

Education Level and Physical Activity

  •    For most countries including Canada, moderate to vigorous physical activity  levels increase with higher education levels
  •    Sedentary rates decline sharply with increased education levels
  •     Vigorous activity- sharpest increase

 

Proportion of U.S. Teens Engaged in Various Doses of Physical Activity  By Education  Level

  •    Parents’ education influences adolescents’ PA in same pattern
  • If parents’ education is:  o < High school: 50  teens engage in vigorous PA  o High school graduate: 54  teems engage in vigorous PA  o Some college: 68  teens engage in vigorous PA

 

Summary of Physical Activity Participation Patterns

  •     Worldwide PA levels are extremely low
  •    Time engaged in PA declines with age
  •    Men are more likely to engage in vigorous exercise, but women tend to engage  in as much, if not more, moderate activity
  •    Low income groups and ethnic minorities tend to participate in less physical  activity than the general population
  •    The higher an individual’s  or parent’s  education level the greater the  participation in physical activity

 

Consequences of Physical Activity and Inactivity

  •    Physically active people have lower overall allLcause mortality rates then  sedentary people
  •        Midlife increase in physical activity is associated with reduced risk of mortality

Morbidity  Disease  in U.S.

  • 14 million Americans have Chronic Heart Disease  –      >1 million have a heart attack each year
  •    18 million have adult-onset diabetes  Type II
  •    50 million have high blood pressure
  •    >120 million are overweight

 

How do we Investigate the Relationship Between PA and Morbidity-Mortality Rates?

  •    Longitudinal Studies

o Large-scale studies that examine the behavior of a specific group of people  over a long period of time

 

 

San Francisco Longshoreman

  •    Participants were thousands of longshore workers
  •    22 year follow-up period  1951-1972
  • Measures:  o Work activity  energy expenditure   o Coronary Heart Disease  CHD  records  o Mortality data
  • Findings:  o Men who had expended 8500 kilocalories-week on the job had a lower risk+of  death from CHD at any age

 

 

Harvard Alumni Study

  •    17,000 Harvard Alumni
  •    16 year follow-up period  1962-1978
  •    Measures:
  • Self-reported leisure time physical activity o Coronary Heart Disease  CHD records   o Mortality data
  • Findings:  o Men had a 53  reduction in all-cause mortality when participating at least 3  hours-week of leisure-time activity
  • On average, active individuals lived 2 years longer than inactive individuals

 

 

Special Populations

  •    True or False?

o People with a disability or chronic disease are insufficiently healthy to  participate in exercise and do not reap benefits from exercise. FALSE

  •    People with a disability or chronic disease are far less active than general  population and are at increased risk for secondary physical and psychological  health problems
  •    23  of people with disabilities are physically active 20 min-day, 3 days-week  versus 33  of the general population
  •     45  of the US population have at least one chronic disease or disability
  •       Access to programs is a major barrier to physical activity for people with a disability
  •      We need to create physical activity opportunities for people with special needs

 

Key Take Home Point

  •    Adopting a physically active lifestyle can positively impact mortality and morbidity  rates for all individuals
  •    So… how do we get people to start and stick with a more physically active lifestyle?

 

Emergence of Exercise Psychology

  •    “Philosophy of physical fitness” – since late 1700s
  •    “Fitness craze” – 1970s and 1980s
  •    Increased emphasis on physical appearance
  •    More recently, the realization that exercise can help reduce heightened levels of  stress
  •     Idea that individuals can play an active role in maintain-improving one’s health

 

Learning More about Exercise Psychology

  •    Databases: MEDLINE, PsycINFO
  •    Professional organizations: American College of Sports Medicine  ACSM ,  Canadian Society for Psychomotor Learning and Sport Psychology  SCAPPS  North  American Society for Psychology of Sport and Physical Activity  NASPSPA

International Society for Behavioral Nutrition and Physical Activity  ISBNPA

 

 

Occupational Opportunities in Exercise Psychology

  •    Higher education
  •     Primary-secondary education
  •    Fitness and wellness
  •    Rehabilitation
  •    Business