воскресенье, 7 октября 2012 г.

Pediatric Physical Activity and Fitness - Cardiopulmonary Physical Therapy Journal

ABSTRACT

The importance of physical activity in childhood and adolescence cannot be overstated. Since adequate amounts of physical activity provide multiple health benefits and will improve or maintain physical fitness, it should be an integral component of children's lives. However, children and adolescents are much less active than in previous decades. The causes of this phenomenon are numerous, including social and environmental factors, and practices in schools. Physical therapists should consider these factors and the unique response to exercise by the pediatric population when prescribing exercise. Physical therapists can intervene to increase regular physical activity in children and adolescents at a variety of levels. At the Individual Level, we can support physical activity in the treatment of children with disabilities and for wellness. At the School Level, we can become active volunteers or consultants to enhance physical activity in the school environment. At the Policy Level, we can support policies that increase opportunities for physical activity in the schools, communities, and society. We need to change the way physical activity is perceived as not only an individual behavior choice, but also the result of many choices made for us in our environment. As physical therapists, we are uniquely positioned to advocate and provide guidance for increased physical activity among children and adolescents, their families, and the society as a whole.

INTRODUCTION

Physical activity can be described as any bodily movement produced by skeletal muscles, while physical fitness is defined as the ability to perform physical activity.1,2 Physical activity can prevent disease-a sedentary lifestyle leads to increased morbidity and mortality, while physical activity confers many positive health benefits to children and adolescents.1,3-6 Physical activity decreases health care costs and improves quality of life and can be individualized to age and ability.7,8 Since adequate amounts of physical activity will improve or maintain physical fitness, a central component of health and wellness, physical activity should be an integral component of children's lives.7 As physical therapists, we are uniquely positioned to advocate and provide guidance for increased physical activity among children and adolescents, their families, and the society as a whole.

The importance of adequate physical activity in childhood and adolescence cannot be overstated. Physical activity provides specific health benefits, including weight management, blood pressure control, and improved musculoskeletal and cardiopulmonary function. The value of physical activity for improved mental health has also been demonstrated for children and adolescents. A connection has been reported between physical activity and the prevention and treatment of depression.9 A lifestyle that lacks physical activity as a child is likely to lead to sedentary adulthood, setting the stage for heart disease, diabetes, high blood pressure, obesity, and some forms of cancer.1 Because children spend an abundance of time in school, this is a prime area for changing the social and physical environment to support and promote a healthy lifestyle, including opportunities for regular physical activity. In addition, since many adults make decisions that impact the lifestyles of children, it is essential for parents, teachers, coaches, and health care professionals to support physical activity.

WHERE ARE WE NOW?

Not so long ago in the US, children had physical education (PE) every day in school. Those who lived close enough walked to and from school, and after school children had to be coaxed indoors from informal games of kickball or Capture the Flag to do homework (written longhand) or eat dinner. Summers were filled with unstructured play, mostly outdoors, and TV was for watching occasionally, since program choices were limited. Fast-forward to a new century where a child can spend an entire school day without PE or active play at recess, only to spend the remainder of the waking hours indoors because of safety concerns or a desire to partake in the myriad of entertainment on television and computers.3,4,10-14 The problem only worsens as cars replace bicycling and walking as the preferred method of transportation.6,9 At the same time, parents and other adults model decreasing amounts of physical activity and increase incidence of overweight and obesity.4,11 There are many sociocultural and environmental factors that affect the activity patterns of children and consequently, their fitness levels.

Children and adolescents are not as active as in previous generations, but what are the current rates of physical activity?3

The first Surgeon General's Report on the state of physical activity and health in Americans was released by the US Department of Health and Human Services (HHS) and the Centers for Disease Control and Prevention (CDC) in 1996.4 The following conclusions concerning adolescents were reported. Nearly half of Americans aged 12 to 21 years are not vigorously active on a regular basis and one fourth report no vigorous activity. Physical activity declines dramatically during adolescence; 72% of 9th graders participate in vigorous physical activity on a regular basis, compared with only 55% of 12th graders. Daily participation in PE by high school students dropped from 42% in 1991 to 25% in 1995. In addition, only 19% of all high school students reported being physically active for 20 minutes or more in the physical education classes they did attend. Children walk or ride bicycles much less than in the past. In 1995, youth aged 5 to 15 walked or cycled 40% less than in 1977. In addition, children make only 31% of trips to or from school of 1 mile or less by walking, and only 2% ride a bicycle.6,9 Trends show an association between inactivity and certain demographic factors. Low socioeconomic status has been related to decreased physical activity, and inactivity is more common among females than males.3 White females are most likely to engage in physical activity while black and Hispanic females are least likely.15,16

We must reconsider our assumption that solely by virtue of their ages, children experience sufficient amounts of activity. Even very young children are at risk. In a recent report, it was found that only16% of kindergarten programs provide daily PE, while 59% have PE 1 to 2 times per week, and 13% provide PE less than once a week. Schools with an increased percent of low-income or minority students are more likely to have no physical education in kindergarten, precisely the population most at risk.5 Even toddlers have fallen victim to this trend of inactivity. A study in the United Kingdom reported low levels of activity in 3 year olds equipped with accelerometers to monitor movement. The toddlers were physically active for only 20 minutes per day.17

The risks of inactivity are numerous, chief of which is obesity. Although increased caloric intake and decreased physical activity can both be implicated, in US adolescents, the decline in physical activity appears to play a much larger role.18 Overweight and obesity in children and adolescents have more than doubled in the past 20 years.3 In addition, this trend persists into adulthood, setting children up for a lifetime of increased risk for disease.1,15 Obesity has been implicated in many diseases in the pediatric population and has resulted in the replacement of the term Adult-Onset diabetes with Type II diabetes, as this condition increasingly includes more children.5,19 Health conditions resulting from overweight and obesity include glucose intolerance, hypertension, and dyslipidemia, and it is not uncommon for children to exhibit all three of these cardiovascular risk factors.5,9,20 Other health problems related to obesity include obstructive sleep apnea, nonalcoholic steatohepatitis, and slipped capital femoral epiphysis.3 In addition, overweight girls are more likely to experience anxiety, loneliness, low self-esteem, and anger.5

Other conditions, common in the pediatric population, present a barrier to participation in physical activity. School age children with asthma are often restricted from participating in physical education or sports because of concern that the asthma will be exacerbated.21 Medical recommendations to manage symptoms and optimize physical performance should be followed to allow the child to participate in PE class and sports.21 It is also a challenge to provide adequate opportunities for physical activity for children and adolescents with cerebral palsy, mental retardation, and other chronic conditions. Lack of physical fitness is more prevalent in people with disabilities due to social and physical barriers.22 Children with disabilities may also be denied opportunities for physical activity because of the emphasis on other life issues resulting from their condition. Finally, concerned parents of children with congenital or chronic conditions may hold them back from activity.

HOW DID WE GET HERE?

Many aspects of the physical and social environment affect the fitness levels of children and adolescents in the United States. Each of these factors points to a potential area of intervention.

In the physical environment, most communities are designed around the automobile; the location of grocery stores and restaurants encourages driving rather than walking.8 It has been demonstrated that 43% of people with safe places to walk within 10 minutes of home meet recommended activity levels, compared to 27% of those without safe places to walk.8 The proximity of housing developments to parks, trails, and greenways has been shown to increase levels of physical activity.8

Social factors such as exaggerated fear of kidnapping contribute to declining numbers of children who routinely walk to and from school.14 In addition, safety concerns in many neighborhoods have been shown to restrict children's performance of physical activity after school hours.10-12 Children are frequently instructed to stay indoors after school when home alone while parents work. Indoor activities are necessarily less physical than those performed outdoors. This, along with increased availability of media entertainment, establishes a preference of many children for the more sedentary activities of watching TV and playing video and computer games. More than 25% of children in the US watch at least 4 hours of TV per day, and TV viewing has been negatively associated with physical activity and fitness patterns.3,15 Even in preschool children, having a TV in the bedroom has a strong relationship to being overweight.6 Young children are exposed to far more visual media than in the past. The number of television programs geared to children, and the expanding market of children's videos, many of which are labeled 'educational,' tempt parents to rely on these for diversions during meal preparation, household chores, working from home, and even during transportation-on portable video/DVD players in cars.

Societal factors reveal other reasons for declining physical activity in children and adolescents. The increase in single-family households and families where both parents work outside the home may limit involvement in sports or other organized physical activities after school. Lack of time, transportation needs, and financial considerations may all factor into a child's inability to participate. It is also increasingly uncommon to see children playing unstructured games together after school, whether in a neighborhood or the local park.14 Sports programs, after-school programs, and safety issues may all be factors in reducing the number of spontaneous neighborhood kickball and football games that occur with children at varying levels of abilities.

Since children and adolescents spend so many waking hours in an academic setting, it is not difficult to make the case that the school environment plays an important role in determining the amount of physical activity available. In the name of academic accountability and budgetary concerns, PE has taken a back seat to other subjects. This is evidenced by the decline in physical education in the 1990s as reported above. Forty four percent of high school students in the US are not enrolled in PE, and Illinois is currently the only state that requires daily PE up through grade 12.23 However, the Youth Risk Behavior Survey (YRBS) reports a slight increase in daily PE programs in 2003.23 Other factors affecting physical fitness include the number of minutes spent in vigorous physical activity during a physical education class, which the majority of high school students report to be less than 20 minutes per class.4 National standards for PE teachers are voluntary, so many children lack adequately trained instructors.13 In addition, the emphasis on sports over instruction and availability of lifetime physical activity is another concern. Students might be more interested in physical activity if it wasn't equated primarily with team sports, but rather promoted with a variety of activities such as martial arts, rock climbing, dancing, roller blading, and skateboarding. In the future, more attention may be paid to the balance of physical activity and academic endeavors in the school environment. There has been no evidence that time spent in PE harms academic performance.9 In fact, a preliminary study found a positive relationship between fitness scores and academic achievement, demonstrating yet another benefit of physical activity. Fit children performed better on cognitive tasks and processed stimuli faster than sedentary children.24

One factor that may affect the participation of children and adolescents in physical activity is the risk involved. Fear of injury may influence a parent's decision not to allow a child to participate in a program of physical activity or sports. Many injuries are the result of improper equipment or the lack of safety equipment such as helmets or faceguards. Many states do not even have requirements for protective equipment in PE classes.13 In addition, many coaches are volunteers with limited training. Good coaching principles can go a long way toward injury prevention. In addition to injuries, excessive physical activity in the pediatric population can lead to menstrual abnormalities and bone weakening.4

HOW ARE CHILDREN AND ADOLESCENTS DIFFERENT THAN ADULTS?

'Children are not just small adults' is a refrain often used by pediatricians. This statement undoubtedly applies to exercise performance. Differences can be seen in cardiovascular and pulmonary responses and metabolic systems. To provide appropriate exercise or activity programs for children and adolescents, it is vital to understand the differences in children's response to exercise as compared with adults.

Cardiovascular differences include alterations in heart rate (HR), cardiac output, and peripheral circulation.21 Heart rates are higher in children at rest and with submaximal exercise, and they decrease with age. At puberty, peak HR begins to fall 7 to 8 beats per minute each decade. As age increases, submaximal HR decreases, but variables such as obesity, heat, and poor cardiovascular fitness, may cause it to remain elevated. Estimating maximum HR with the '220 minus the age' formula doesn't become meaningful until the late teenage years, as maximum heart rates can vary too widely before this age.25 Recovery to resting HR occurs more quickly in children than adults. Resting cardiac index is about the same for children and adults when body size is taken into account, 3-5 L/min per m^sup 2^. However, a lower cardiac output is observed in children relative to adults at a given exercise level, due to a lower stroke volume. During childhood and adolescence, the concentration of hemoglobin in the blood increases progressively, improving the rate of oxygen delivery. Oxygen extraction is improved in children over adults, measured by a higher arterial-to-venous difference.21

The work of breathing during exercise is greater in children than adults.26 This is due to children's smaller exhaled volumes per minute at the same workload. However, because of higher respiratory rates, total minute ventilation is higher at the same workload when body size is taken into account. This high total minute ventilation per body weight translates to greater work of breathing in children than adults at the same level of exercise.26 However, since anatomical dead space is smaller in children, a higher portion of inspired air is delivered to the alveoli.25

Disparity in exercise performance in children and adolescents can be due to differences in size. Measurements should take body mass into consideration, so that the effects of size can be considered separately. Other variations may be due to differences in sex. In general, girls have higher submaximal and maximal heart rates than boys. Until puberty, hemoglobin concentration and blood volume are about equal; after puberty, girls tend to have lower blood hemoglobin levels. In addition, girls tend to have lower maximal ventilation compared to boys.21

Aerobic capacity, determined by VO^sub 2^ max, increases with age and maturation primarily due to increased size.26 In boys, VO^sub 2^ max increases steadily from age 6 to 18 and then decreases with age; VO^sub 2^ max in girls increases until 14 to 16 years of age and then starts a steady decline.25 At puberty, boys generally have greater muscle mass, and girls have greater body fat, resulting in higher VO^sub 2^ max for boys.21

Temperature regulation during exercise is more difficult for children than adults for several reasons. Exercise produces heat that dissipates through evaporation by sweating or convection on the skin's surface. In children, the amount of sweat produced by each sweat gland is decreased.25 Increased blood flow to the skin and muscles results in decreased venous return that can increase HR. Since heart rates are already higher in children, it can be difficult for them to meet the increased demand. In addition, children have a larger surface area to mass ratio, which results in greater convection, resulting in increased heat loss in cold temperatures. Therefore, children and adolescents will tolerate physical activity for shorter periods in extreme temperatures than will adults.25

WHERE DO WE WANT TO BE?

To meet a goal of Healthy People 2010 'To improve health, fitness, and quality of life through daily physical activity,' objectives must be established and progress toward these objectives measured.27 The US Dept of Health and Human Services' Healthy People 2010 and the President's Council on Physical Fitness and Sports established objectives related to physical activity in children and adolescents. The Youth Risk Behavior Survey (YRBS), National Health and Nutrition Examination Survey (NHANES), and other data sources provided information on the status of progress toward the objectives specified in Healthy People 2010.27

1. Objective 22-6: Increase the proportion of adolescents who engage in moderate physical activity for at least 30 minutes on 5 or more of the previous 7 days. In 1997, 20% of students in grades 9 through 12 met this objective, and the target is 30%.

2. Objective 22-7: Increase the proportion of adolescents who engage in vigorous physical activity that promotes cardiorespiratory fitness 3 or more days per week for 20 or more minutes per occasion. In 1997, 64% of students in grades 9 through 12 met this objective, and the target is 85%.

3. Objective 22-8: Increase the proportion of the Nation's public and private schools that require daily physical education for all students. In 1994, the percent of middle and junior high schools that met this objective was 17%, and the percent of senior high schools was only 2%. The targets for middle/junior high schools and senior high schools are 25% and 5%, respectively.

4. Objective 22-9: Increase the proportion of adolescents who participate in daily school physical education. In 1997, 27% of students in grades 9 through 12 met this objective, and the target is 50%.

5. 22-10: Increase the proportion of adolescents who spend at least 50% of school physical education class time being physically active. In 1997, 32% of students in grades 9 through 12 met this objective, and the target is 50%.

6. 22-11: Increase the proportion of children and adolescents who view television 2 or fewer hours per day. From 1988-1994, 60% of persons aged 8 to 16 years met this objective, and the target is 75%.

Other established goals affecting the pediatric population address the issue of access to opportunities for physical activity, such as availability of school facilities after hours, and increased proportion of trips made by walking and bicycles.27 The individual recommendations for adolescents include daily physical activity for a total of 30 minutes at moderate intensity, with an acknowledgement that greater amounts of physical activity are even more beneficial.4

HOW DO WE GET THERE?

There are many ways to measure the components of physical fitness, ie, cardiorespiratory and muscular endurance, muscular strength, flexibility, agility, and body composition. In 1966, the President's Challenge Physical Fitness Award Program started collecting measures of fitness in school-aged children.28 Measuring and tracking changes in these components provides a report card for meeting fitness goals in children and adolescents, individually, and as a group. These tools can be obtained at www.presidentschallenge.org or www.fitnessgram.net.28,29

Endurance is the ability of the body to continue the performance of a task and depends on oxygen transport, the ability of the heart and lungs to pump oxygenated blood to muscles and tissues and dispose of the waste products of metabolism. Endurance can be measured by a variety of tests in different modes. Walking and running tests include the 1-mile walk/run, the 12 or 6 minute walk, the shuttle test, and treadmill tests that incrementally increase speed and incline such as the Modified Balke protocol.30 (For information on administering these tests, see Ohtake's article on exercise testing elsewhere in this issue). Other endurance testing modes include bicycle ergometer tests, such as the McMaster Cycle Test, a 3-mile bicycle ride, a 400-meter swim, or a 3-minute step test.30,31 There are standards for many endurance tests with which to compare a child's performance time.

Measuring muscle strength by manual muscle testing is second nature to physical therapists. In addition to this assessment, there are standards for measuring the number of curl-ups and pull-ups/push-ups performed in one minute.28,30 Likewise, measuring range-of-motion to determine flexibility is a standard practice of physical therapists. The Sit-and-Reach test is another measure of the flexibility of the lower extremities and the lower back and standards are also published for this test.28,30

Body composition, in addition to weight, is another measure of physical fitness. The Body Mass Index (BMI) is a useful tool to assess a child's weight for height, but is measured differently for children than adults, using growth charts to take into account age and sex. Also, normal ranges for BMI are not defined below 3 years of age. The American Academy of Pediatrics recommends the BMI as the primary tool to define childhood overweight and obesity.3 A BMI calculator specifically for children can be found at www.getkidsinaction.org or www.cdc.gov/growthcharts.32,33 Another tool to measure the ratio of lean body mass to fat is skin-fold measurement. These can be taken at several sites, and in children, the triceps and subscapular measurements can be averaged together and compared to a standard.31

An exercise prescription for children and adolescents, as for adults, should include the components of mode, frequency and duration, and intensity. In addition to these components, physical therapists should consider other issues, such as maturation and skill level, the school environment, and safety. Arguably, the overall goal of an exercise program for the pediatric population is to establish a lifelong habit of regular physical activity. This program should change with the child's developmental stage, interests and abilities, and available resources. For young children, active play in place of an exercise program is recommended.

The most important aspect of selecting a mode for children and adolescents is to find an activity that is enjoyable, with the duration and frequency dependent on the chosen mode. The variety of possible activities is endless and may include group or individual activities (Table 1). Group activities provide socialization and may appeal to many children, but those who have less self-confidence or limited skills may not feel comfortable in a group setting.

Exercise intensity is an important component of any exercise prescription and it allows the tracking of the response to activity. Even though heart rate monitoring is a reliable measure of intensity, few children who are able are willing to track this regularly, with the exception of the student athlete in training. The Rating of Perceived Exertion (RPE) is an easy tool for children to learn and continue to use during various tasks involving physical activity and has been correlated with HR.30 There is also a reliable RPE scale for young children which includes faces depicting various amounts of effort.34 The OMNI rating scale of perceived exertion is another valid and reliable measure for use with children.35,36

Energy expenditure of daily physical activity in children with diabetes or obesity should be considered, so that caloric intake can be taken into account. One approach presented by Bar-Or37 is to assign 'exercise exchanges' equal to 100 kilocalories to various physical activities. The duration of the activity depends on the body mass of the child, with less time needed for children with greater body mass. Another tool for determining energy cost of particular activities is the Compendium of Physical Activities, published by the President's Council on Physical Fitness and Sports.38

Safety considerations are more important in children because children are physically and emotionally immature. Excessive exercise or sports trauma has the chance of causing overuse injuries or injury to the epiphyseal growth plate.30 The risk of injury can be decreased by the use of appropriate safety equipment, adequate skills preparation, and matching athletic opponents by size, skill, and maturation levels.25 Also, adequate training and supervision and appropriate clearance for sports by a pre-performance physical is recommended.

WIDER CIRCLES OF INFLUENCE

Physical therapists often think in terms of one-on-one interaction with a patient or client and are probably most comfortable with this level of interface. However, there are multiple levels of intervention in the Social Ecological Model, also known as the Multilevel Model that impact the physical fitness of children and adolescents (Figure 1).39 The many factors that influence physical activity necessitate a multileveled approach and physical therapists are uniquely positioned to intervene at a variety of levels.

The Individual Level

When a child or adolescent is referred to physical therapy, we should consider the patient's long-term physical fitness in addition to the primary reason for the PT consult. Make a routine of talking to patients and their parents about the importance of regular physical activity; by addressing this issue you are demonstrating its importance. One of the goals for discharge from rehabilitation services should be the ability of the patient or caregiver to carry out a regular program of physical activity to improve health in the long-term. Physical activity should also be supported for children with disabilities, especially in light of evidence that persons with developmental disabilities have much lower levels of fitness.22 The American Physical Therapy Association is collaborating with the Health and Human Services Office on Disability in a nationwide initiative that matches physically fit mentors with children who are disabled to provide guidance and training in physical activity.40 This 'buddy system' strategy illustrated by, 'I Can Do It, You Can Do It' is recommended by the CDC's Task Force on Community Preventive Services to increase physical activity.6

When prescribing an exercise program, take into account not only the social and physical environment in which the client lives, but identify and address any apparent barriers. Such barriers have been shown to be among the most powerful predictors of performing a recommended health behavior.41 Think about prescribing exercise not in terms of what you know the patient should do or what you want the patient to do, but start with what they will do, even if the activity is modest or low intensity. The aim is to get the child engaged and not overwhelmed by an intricate or demanding program. Become familiar with resources available to the child and family locally as well as nationally. Many resources and tools are available on the Internet (Table 2).

Assessing the readiness of an older child or adolescent to participate in physical activity is crucial to the success of an exercise program. The Transtheoretical Model, also known as The Stages of Change, is a concept to assess the willingness of an individual to adopt a change in behavior.42 Identifying the stage of readiness of an individual will help you tailor the type and amount of information you give. This strategy can be delivered and followed up on in person, or by telephone or mail (Figure 2).6 As you may know from your own experience, when patients or clients reach the stage where an activity program is sustained, encouragement and continued support is still needed and appreciated.

And don't forget that you can be a role model for others by maintaining a regular physical activity program. Children, especially teenagers, are quick to identify a 'phony' that doesn't take the advice they dispense. They will notice whether you take the stairs instead of the elevator to get to the treatment room, or how close you park your car to the clinic entrance.

The Group/Interpersonal Level

There is some evidence that parents and other adult role models influence the physical activity levels of children and adolescents.2,8 A program of physical activity should intuitively be more successful if it includes the entire family, but evidence in this area is inconclusive, and schoolbased interventions have been found to be more effective.6,9 This area would benefit from further well-designed studies. Building or strengthening social networks of peers to provide support for increased physical activity has been shown to be effective.6,9 Examples may include walking groups with peers, or joining a health club or a exercise class with a friend.

Bar-Or37 has written extensively on pediatric exercise and notes 'children with a 'visible' defect often decline to exercise with their healthy peers but gladly join a program with other children who have a similar condition.' Physical therapists are in a prime position to set up an 'exercise support group' for children with a chronic disease or disability, provided infection control or other special accommodations are considered. Another strategy to consider is to join with other health care professionals, eg, pediatricians, nutritionists, and health behavior experts, to develop or strengthen interventions to support physical activity for children. For example, Jim Zachazewski and Laura Healey, physical therapists in Massachusetts, developed a program with input from childhood educators, child life specialists, and nutritionists. 'Kids On The Move' is a program that provides guidance for a healthy lifestyle.43

The Institutional (School) Level

Due to the vast number of hours children spend in school, this is a prime area to effect change in the physical fitness of our youth. Physical activity levels have been shown to increase as a result of school-based interventions.4,6,9 By intervening at this level we could affect a majority of children in the country. Physical therapists who work in the school system have an inside view of ways to enhance physical activity in a particular school. However, any interested physical therapist can offer to present a session about the benefits of physical activity to any class or after-school program. Don't forget about children in preschool and daycare settings-activity patterns are set early in life. School-based health clinics or school nurses can identify and counsel children at risk for obesity as well as track effects of activity on a chronic health problem such as asthma or diabetes. Volunteering or contracting your services to these children to complement the school's efforts would be invaluable.

There is strong evidence to recommend making changes in PE classes as a way to significantly increase levels of physical activity in children.6,9 Physical therapists have the skills to consult with a PE department to assess developmentally appropriate, aerobic, and strengthening aspects of a PE program. Many of the activities available to children require particular skills, such as throwing or kicking a ball, swinging a bat or racquet, or mastering a sequence of movements. Thus, it is important to give children the opportunity to learn these skills in a nonthreatening environment. If a physical education class where these skills are taught is high pressure or intimidating, children may never develop the self-efficacy needed to accomplish these skills and this may lead to life-long avoidance of these activities. The actual levels of activity in PE classes should be assessed. The amount of time elementary school children spend being physically active in PE has been shown to increase with school-based interventions.4 Activity levels can be increased in current PE classes by substituting soccer for softball or having the entire team run the bases when a batter makes a base hit.6,9 The most promising evidence for intervening in the area of physical education is a recent report demonstrating that even slight increases in school PE can reduce the number of children classified as overweight. A mere 1-hour increase in physical education per week resulted in a 31% drop in BMI among overweight and at-risk girls in first grade.5 Also of importance is the finding that modifying the PE curriculum is universally effective-across racial, ethnic, and socioeconomic status, with girls and boys, and in urban as well as rural settings.6

The Community Level

To support physical fitness, the physical and social environment must be conducive to physical activity. There is strong evidence for the effectiveness of community-wide campaigns to promote physical activity.6,9 Physical therapists can write newspaper or magazine articles and letters to the editor with the purpose of promoting activity. Physical activity has been shown to increase when access to places for physical activity increases.6,8,9 Physical therapists can look in her or his own community to identify ways to enhance physical activity for all its residents. An assessment of the presence and continuity of walking and biking trails can be performed and the results presented at a town council meeting.44 Volunteer or contract your services to a local YMCA or community center for sports or exercise classes. Spurred on by an increase in children's sports injuries, Danny Smith, a PT in Tennessee, holds clinics for Little League coaches on preventing injuries.43 Join a neighborhood watch or start a community group to address the safety in neighborhoods to make them more attractive for physical activity. One recommendation is to encourage schools to make facilities available for community members to use after school hours or in inclement weather, such as basketball courts, a swimming pool, or hallways for walking.

The Policy Level

The way to affect the largest number of youth is through a change in policy. There are many opportunities to advocate for local policy change to enhance physical activity in our pediatric population.11 Become active on a Town Council to advocate for walking/bicycle trails or accessibility to sports or playground equipment. The Surgeon General's Report recommends advocating for daily PE for grades K-12 with a physical education specialist.4 Attend School Board meetings to monitor policies and advocate for increasing PE requirements, increased physical activity in after-school programs, or not withholding recess as a punishment. On a State or National level, physical therapists can advocate for public health policies to enhance physical activity. The National Association of State Boards of Education provides sample policies for use at the State, school district, or individual school level to promote physical activity in schools and communities.45 Policies of reimbursement by insurance companies are another area of intervention. Since Medicare recently changed its stance and now classifies obesity as a disease, this could increase the coverage for treatment of obesity by the government and the many third party payers who follow their lead.46 We should advocate for medical insurance coverage of physical activity programs for children with or at-risk of overweight and obesity.

CONCLUSION

As clinicians, we need to think outside the box of the treatment rooms, rehab departments, or hospital wards where we treat children and adolescents one-on-one. We should consider enhancing physical activity at the many other levels of intervention.11 As academicians, we need to ensure that our PT and PTA students have the knowledge and skills to practice in the wider circles of intervention and that they demonstrate this in an accredited program. As community members, we need to hold our schools and neighborhoods responsible for giving all of our children the knowledge, skills, and opportunities not only for physical activity during the school day, but outside the school environment as well. As citizens, we need to support laws that make the physical environment safe and available for physical activity and advocate for those most vulnerable in our society, the children. We need to change the way physical activity is perceived. It is not only an individual behavior choice to be active or not, but also the result of many choices made for us in our environment.

If we are successful in bringing about change to increase the physical activity of children and adolescents for the long term, which in turn can lead to increased physical fitness, we have the potential to change the health of future generations. It is APTA's position that physical therapy is a health profession whose primary purpose is the promotion of optimal health and function-increasing physical activity in those with whom we interact fulfills this important role.

[Reference]

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[Author Affiliation]

Anne Mejia Downs, PJ, MPH, CCS

Department of Physical Therapy, Indiana University, School of Health and Rehabilitation Sciences, Indianapolis, IN Department of Rehabilitation Services, Clarian Health Partners, Indianapolis, IN

[Author Affiliation]

Address correspondence to: Anne Mejia Downs, PT, MPH, CCS, IU School of Health & Rehabilitation Sciences, Coleman Hall 120, 7740 W. Michigan Street, Indianapolis, IN 46202-5119 Ph: 317-278-1875, FAX: 317-278-1876 (andowns@iupui.edu).