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Keywords:

  • physical activity;
  • physical fitness;
  • cognition;
  • school connectedness;
  • school absenteeism;
  • child and adolescent health;
  • coordinated school health programs;
  • academic achievement;
  • achievement gap;
  • socioeconomic factors

Abstract

  1. Top of page
  2. Abstract
  3. OVERVIEW AND DISPARITIES
  4. CAUSAL PATHWAYS AFFECTING EDUCATIONAL OUTCOMES
  5. WHAT CAN SCHOOLS DO TO INCREASE LEVELS OF PHYSICAL ACTIVITY AND FITNESS?
  6. PROVEN OR PROMISING APPROACHES
  7. SUMMARY
  8. REFERENCES

OBJECTIVES: To outline the prevalence and disparities of physical activity among school-aged urban minority youth, causal pathways through which low levels of physical activity and fitness adversely affects academic achievement, and proven or promising approaches for schools to increase physical activity and physical fitness among youth.

METHODS: Literature review.

RESULTS: A large proportion of youth is insufficiently physically active. Estimates of population-wide levels of physical activity indicate that Black and Hispanic youth are less physically active than White youth, with disparities particularly evident for females. The population segments of youth with lowest levels of physical activity and fitness also have least access to school-based physical activity opportunities and resources. Physical activity affects metabolism and all major body systems, exerting powerful positive influences on the brain and spinal cord and, consequently, on emotional stability, physical health, and motivation and ability to learn. The cornerstone of school-based physical activity programs should be a high-quality physical education program based on national standards. Such programs are strongly recommended by the Task Force on Community Preventive Services as a way to increase physical activity and physical fitness among youth.

CONCLUSIONS: Physical inactivity is highly and disproportionately prevalent among school-aged urban minority youth, has a negative impact on academic achievement through its effects on cognition, and effective practices are available for schools to address this problem. Increasing students' physical activity and physical fitness can best be achieved through a comprehensive approach that includes physical education, wise use of recess and after-school times, co-curricular physical activity opportunities, and bicycling or walking to and from school.


OVERVIEW AND DISPARITIES

  1. Top of page
  2. Abstract
  3. OVERVIEW AND DISPARITIES
  4. CAUSAL PATHWAYS AFFECTING EDUCATIONAL OUTCOMES
  5. WHAT CAN SCHOOLS DO TO INCREASE LEVELS OF PHYSICAL ACTIVITY AND FITNESS?
  6. PROVEN OR PROMISING APPROACHES
  7. SUMMARY
  8. REFERENCES

Physical activity has dramatic effects on individuals' physical and mental health and on population-wide health status. Unacceptably low levels of physical fitness and physical activity have contributed to increasing prevalence, in the past decades, of overweight and obesity among youth.1–6 Prevalence of overweight and obesity is highest among minority female children and adolescents2,3,6 and among Mexican-American boys.4,5,7–9 While levels of physical activity are unacceptably low for most adolescents, they are particularly low for Black and Hispanic females. The beneficial effects of physical activity and physical fitness on physical health are very well established, and there is increasing evidence of effects on mental health. An emerging literature documents the ways in which physical activity, fitness, and school-based physical activity programs, such as physical education, favorably affect educational outcomes.

Physical activity and resulting fitness affect physical health via the cardiovascular, musculoskeletal, endocrine, and neurological body systems. In adults, physical activity or physical fitness has been associated with reduced risk of cardiovascular disease,10–13 cerebrovascular disease,14–16 various cancers,10,17–21 diabetes,10,14,22 depression and anxiety,23–25 all-cause mortality and survival,11,26–28 and with enhanced cognitive functioning.29–31 The causal effects of physical activity and fitness on health status are most apparent in adults since, in adults, they have the opportunity to accrue over decades.

Physical activity and fitness are also powerful markers of child and adolescent health.32 Physical activity and/or aerobic fitness has been associated with reduced fatness33–41 and blood pressure,35,42,43 and improved bone health.44–46 Relatively strong (observational) evidence indicates the positive effects of physical activity and fitness on mental and emotional health of youth.32,47–52

Physical fitness and aerobic fitness decline as youth transition from childhood and middle school to adolescence and high school53–56 and this may be especially true for females, in general,57–62 females who mature early63,64 and youth who are overweight.41,56 Males have higher levels of typical physical activity than females; for both, activity tends to decline over the progression from elementary and middle school through grade 12.54 Estimates of population-wide levels of physical activity indicate that Black and Hispanic youth are less physically active than White youth, with disparities particularly evident for females.54

Almost two thirds of the nation's high school students do not meet one recommended level of participation in physical activity: being physically active enough to raise heart rate and breathe hard some of the time at least 60 minutes per day on 5 days of the prior week. About 20% more of White high school students met this criterion than Black or Hispanic high school students (37.0% vs 31.1% and 30.0%, respectively). About 25% more of White female high school students met the criterion than Black or Hispanic females (27.9% vs 21.0% and 21.9%). The rates among high school males were 46.1% for Whites, 41.3% for Blacks, and 38.6% for Hispanics. Another criterion is not being physically active for at least 60 minutes on any of the prior 7 days. By this measure, prevalence among Hispanic females was approximately twice as high and, prevalence among Black females more than 150% as high, as prevalence among White females (35.2% and 42.1% vs 16.7%) (Figure 1).

image

Figure 1. Percentage of Female High School Students in the United States Who Did Not Participate in Physical Activity* by Race/Ethnicity** *Did not participate in 60 or more minutes of any kind of physical activity that increased their heart rate and made them breathe hard some of the time on at least 1 day during the 7 days before the survey. **B > H > W. Source: CDC, National Youth Risk Behavior Survey, 2007.

Download figure to PowerPoint

In summary, a large proportion of youth is insufficiently physically active or inactive. This is especially true for females and immigrant children and adolescents.65 Due to the magnitude of the problem, this behavior confers a large population attributable risk with respect to a variety of health and educationally relevant outcomes.

Those population segments of youth experiencing disparities in level of physical activity and fitness also have disparities in access to school-based physical activity opportunities and resources. Opportunities for physical activity have been associated with access to school sports facilities and equipment storage space.66 Subjective and objective measures of recreational opportunities have been associated with physical activity levels among youth, including adolescent girls.67–69 Recreational facilities are not equally distributed. Poor urban minority youth have less access to safe recreational facilities.70,71 The low level of physical activity among Black and Hispanic adolescent girls is largely attributable to the nature of the schools they attend.72 Not surprisingly, there is an inverse relationship between school's median household income and average body mass index.73 Adequate investment of financial and human resources is associated with greater opportunities for physical activity.66

CAUSAL PATHWAYS AFFECTING EDUCATIONAL OUTCOMES

  1. Top of page
  2. Abstract
  3. OVERVIEW AND DISPARITIES
  4. CAUSAL PATHWAYS AFFECTING EDUCATIONAL OUTCOMES
  5. WHAT CAN SCHOOLS DO TO INCREASE LEVELS OF PHYSICAL ACTIVITY AND FITNESS?
  6. PROVEN OR PROMISING APPROACHES
  7. SUMMARY
  8. REFERENCES

Recent advances in molecular biology detailing the causal mechanisms through which physical activity influences brain chemistry and cognitive function have explained what the Greeks knew, intuitively, thousands of years ago—a strong mind and body are intimately related. Physical activity affects metabolism and all major body systems, exerting powerful positive influences on the brain and spinal cord and, consequently, on emotional stability, physical health, and ability to learn. This section reviews causal pathways by which physical activity and fitness may affect educational outcomes.

The strongest evidence supports direct effects of physical activity on cognition. Other plausible, albeit speculative, pathways mentioned are connectedness with school, absenteeism, and dropping out.

Cognition

An emerging body of knowledge documents beneficial cognitive effects of physical activity among animals74 and among human adults of different ages.29,30,75–79 Exercise may favorably affect learning and memory ability associated with aging,29,30,76,80,81 and recovery from brain or spinal cord injury;81 it may also help to minimize adverse effects from chronic neurogenerative disease.82,83 The greatest cognitive benefits of physical activity may be for those with the lowest cognitive ability.77,84 Studies conceptualize and define physical activity and fitness and cognition in different ways, complicating the task of delineating which specific aspects of physical activity or fitness (eg, cardiorespiratory, strength, flexibility, balance, speed, agility) are causally related to which specific aspects of cognition (eg, executive function, verbal, auditory and visual memory, inhibition, attention, response speed). Nevertheless, current knowledge strongly indicates that physical activity can benefit aspects of cognition, thereby favorably affecting educational outcomes. Recent literature reviews on physical activity or physical fitness and cognition29, 79, 80, 85–87 have all reached the same conclusion: physical activity (or aspects of physical fitness) favorably affects cognitive functioning.

Ploughman88 provides a concise summary of how exercise may affect executive functioning: (1) increasing oxygen saturation and angiogenesis, (2) increasing brain neurotransmitters (eg, increasing serotonin), and (3) increasing brain-derived neurotrophins that support neuronal differentiation and survival in the developing brain. Diverse research on exercise and energy metabolism, exercise and molecular causal pathways affecting the brain, and exercise and memory and learning (eg, brain-derived neurotrophin factors and resultant increased neuronal plasticity) provides a compelling rationale for ascribing a role in cognition to physical activity. It is likely that the effects of physical activity on cognition would be particularly important in the highly plastic developing brains of youth.88

Among children, physical activity, physical fitness, and cognition have been investigated, from a variety of educationally relevant perspectives beyond the cellular level. Interpretation of this literature is complicated by several factors, most notably, variations in educational outcome measures. Some intervention studies analyzed on-task behavior during instruction84 or concentration;89 others used standardized achievement tests.90–92 Some observational studies used standardized test scores;93,94 others used grades50 or other measures of cognitive function (eg, neuroelectrical indices of memory, attention and response speed),95 or interference control (a component of executive control).96 Some consider physical activity,50,93 others consider physical fitness.94–96 Three recent literature reviews conclude that school-based physical activity programs may result in short-term cognitive benefits,97 improve cognitive functioning among children,98 and do not hinder academic achievement.99 These different kinds of evidence support the case for favorable effects of physical activity or physical fitness on cognitive functioning of youth.

Connectedness

No studies have specifically evaluated the relation between school-based physical activity programs and connectedness, but such programs would seem a natural context in which youth might engage and cooperate with peers, learn teamwork, and excel physically. These behaviors would be expected to foster engagement in school. Connectedness might also be enhanced via decreased overweight and obesity.

The transition from childhood to adolescence is a time when mental and emotional problems increase.100–103 Problems such as anxiety and depression, among others, and resultant internalizing and externalizing behaviors, can have powerful adverse effects on school success, both academic and social. Physical activity favorably affecting indices of mental and emotional health can promote improved overall well-being and, indirectly, connectedness with peers and teachers at school.104–106

Absenteeism

School-based physical activity programs may improve attendance by reducing obesity, which has been associated with absenteeism,107,108 by increasing connectedness, and by favorably affecting the health status of children with asthma. A consistent finding is that physical activity can improve cardiopulmonary fitness among youth with asthma.109–112 Physical activity has also been reported to have favorable effects on physiological indices other than fitness113,114 and to improve quality of life.114,115 Exercise-induced asthma should be addressed, not by avoiding exercise, but by increasing physical fitness.116 School-based physical activity programs can help youth with asthma to learn and maintain healthy physical activity habits.

Dropping Out

One study investigated the relation between participation in school-based physical activity programs and dropout. Findings were based on repeated measures collected as part of the National Educational Longitudinal Study. Dropout rates were lower for youth who consistently participated in interscholastic sports.117 This is not meant to imply that school-based physical activity programs are a panacea for the dropout problem. However, to the extent such programs are enjoyable for youth and foster teamwork, cooperation, and physical fitness, youth who participate may be more connected with and engaged in school, and more likely to attend and remain in school.

WHAT CAN SCHOOLS DO TO INCREASE LEVELS OF PHYSICAL ACTIVITY AND FITNESS?

  1. Top of page
  2. Abstract
  3. OVERVIEW AND DISPARITIES
  4. CAUSAL PATHWAYS AFFECTING EDUCATIONAL OUTCOMES
  5. WHAT CAN SCHOOLS DO TO INCREASE LEVELS OF PHYSICAL ACTIVITY AND FITNESS?
  6. PROVEN OR PROMISING APPROACHES
  7. SUMMARY
  8. REFERENCES

School administrators, trying to raise standardized test scores, may mistakenly believe that physical education curricular time should be sacrificed and reallocated to reading, mathematics, and science. There is currently no evidence indicating that this strategy is, in fact, effective in increasing standardized test scores; in fact, a growing body of evidence shows that increased time for physical education and other school-based physical activity programs is associated with either a neutral or positive impact on academic outcomes. A variety of consensus recommendations are available to guide the conceptualization of school-based physical activity/education programs.118–122

Increased student physical activity and physical fitness can best be achieved through a comprehensive approach118 that includes physical education, wise use of recess and after school times, co-curricular physical activity opportunities, and bicycling or walking to and from school. The nature and scope of school-based physical activity/education programs will vary with the resources available (eg, human, physical, and social environmental) and with the level of commitment by school administrators. Community linkages can ease access to community recreational facilities. Cooperation of the local police can help ensure safety as students walk to and from school. In some localities, schools may represent the main recreational resources within the community.

The cornerstone of school-based physical activity programs should be a high-quality physical education program based on national standards. Such programs are strongly recommended by the Task Force on Community Preventive Services as a way to increase physical activity and physical fitness among youth.123,124National Standards for Physical Education published by the National Association for Sport and Physical Education119 posit that a physically educated person:

  • 1
    Demonstrates competency in motor skills and movement patterns needed to perform a variety of physical activities.
  • 2
    Demonstrates understanding of movement concepts, principles, strategies, and tactics as they apply to the learning and performance of physical activities.
  • 3
    Participates regularly in physical activity.
  • 4
    Achieves and maintains a health-enhancing level of physical fitness.
  • 5
    Exhibits responsible personal and social behavior that respects self and others in physical activity settings.
  • 6
    Values physical activity for health, enjoyment, challenge, self-expression, and/or interaction.

Physical education class is an important opportunity for youth to be active and to learn self-awareness, self-regulation, and other social-emotional skills, such as teamwork and cooperation. As with any school subject, quality is greatly influenced by teacher preparedness and enthusiasm. Opportunities for professional development can facilitate both. Another critical factor is the use of a sound physical education curriculum, consistent with the national physical education standards and the evidence-based characteristics of effective curricula. The Centers for Disease Control and Prevention's (CDC's) “Physical Education Curriculum Analysis Tool” can help school districts select or develop such a curriculum.

Increasing participation by students least inclined to be active may require a new approach to physical education. Many youth really enjoy school physical activity/education programs. This can be true for many more. Opportunities for enjoyable play at school can dramatically affect youth development125 and foster school connectedness and engagement. Identifying and implementing physical activities that youth enjoy, particularly those who are less inclined to participate, is a key strategy in conceptualizing an effective physical education program. Research,126–128 as well as common sense, dictates that if students enjoy physical education, they will be more inclined to participate actively and to be engaged.

A school environment that motivates and enables youth to be physically active can serve to promote physical activity. Such an environment is determined in great part by the availability of space, equipment, and supplies. A safe environment is essential. Safety is achieved through design and maintenance of facilities, use of appropriate protective equipment, and adequate supervision. There is a well-documented inverse relationship between environmental safety and physical activity.129–132

The psychological environment is also important. If recreational time is characterized by negative social interactions, benefits will be limited. Some youth (eg, overweight girls) may choose to avoid physical activities altogether. A psychological environment characterized by encouragement to be active and minimization of teasing and other aggressive behaviors will have benefits beyond physical activity, and is considered a national standard for physical education.119 Social support has been positively associated with level of physical activity among adolescent girls.67

While emphasizing increased physical activity and fitness, schools can also help youth to learn, value and practice respectful and cooperative behaviors, and provide attentive social support for development of physical self-efficacy.133 The interpersonal interactions characteristic of many physical activities and learned in the context of a physical activity program can have important spillover effects on school climate. Like all school programs, physical activity programs require insight and leadership.66

Extracurricular activities, before and after school and in the summer, can greatly contribute to the acquisition of regular physical activity habits. For many youth, participation in sports teams is an important context for physical activity and a powerful element of connectedness with school. As a matter of course, competitive sports tend to limit themselves to those with the greatest athletic abilities. Sports teams are not the answer for all students. Encouragement to be physically active needs to be intentionally directed toward those who need it most: the overweight and those with the least athletic abilities. Alternatives to competitive sports include dance, martial arts, walking, and physical activity games.

Recess, a time for play, may be an appropriate time to promote physical activity. Some data suggest that school-day recess playtime can contribute significantly to children's overall levels of moderate to vigorous physical activity.134 Students, however, are not all equally likely to be physically active during recess.135 For some, free time for relaxation may be advantageous.

Children who walk or bike to school have higher levels of physical fitness and physical activity than those who do not.136 Walking to and from school may be an option for some students, particularly in urban areas, but the majority of children in the United States do not walk to school137–140 and the percentage of children who do has declined sharply over the past decades.139,140 Longer distances and safety concerns have been identified as barriers to walking to school.137,138 Active transportation to school has been identified as a potentially important strategy to increase physical activity among low-income minority youth.141 The CDC142 and the National Center for Safe Routes to Schools143 have developed programs and resources to encourage walking and biking to school.

Academic classroom time can be beneficially relieved with brief breaks for stretching or other activity associated with physical well-being. A classroom physical activity program integrating academic and physical activity curriculum—“TAKE 10!”—was found to increase levels of moderate physical activity among elementary level students.144 Another intervention, comprising two 10-minute lessons per day taught by classroom teachers, was found to yield increased levels of energy expenditure.145 Both interventions achieved beneficial physical activity goals without undermining academic goals.

PROVEN OR PROMISING APPROACHES

  1. Top of page
  2. Abstract
  3. OVERVIEW AND DISPARITIES
  4. CAUSAL PATHWAYS AFFECTING EDUCATIONAL OUTCOMES
  5. WHAT CAN SCHOOLS DO TO INCREASE LEVELS OF PHYSICAL ACTIVITY AND FITNESS?
  6. PROVEN OR PROMISING APPROACHES
  7. SUMMARY
  8. REFERENCES

Most evaluation studies focus on the extent to which school-based physical activity/education programs increase physical activity and physical fitness. An ample number of studies document that well-conceived programs, implemented by skilled staff, can increase levels of both physical activity and physical fitness among youth.146–151 Based on synthesis of the scientific literature on evaluations of school-based physical education programs, the Task Force on Community Preventive Services123 strongly recommends longer physical education classes and increased time engaged in moderate to vigorous activity as a strategy for increasing physical fitness.

An emerging body of evidence suggests that school-based physical activity programs, such as physical education, have either a neutral or a positive impact on educational outcomes; there appears to be no evidence to support the notion that reducing time for physical education is a sound strategy for increasing academic achievement.97–99 In the most recent and comprehensive review, Trudeau and Shepard99 concluded, based on a review of 7 quasi-experimental and 9 cross-sectional studies, that allocating more curricular time to physical activity programs, and less time to other academic subjects, does not affect the academic performance of elementary school students negatively and that an additional curricular emphasis on physical education may result in small absolute gains in academic achievement. A recent cross-sectional study not included in the Shepard review examined the association between time spent in physical education and academic achievement among a nationally representative sample of more than 5000 students in the US Department of Education's Early Childhood Longitudinal Study, Kindergarten Class of 1998 to 1999. Carlson et al93 found a small but significant benefit for academic achievement in mathematics and reading for girls enrolled in higher amounts of physical education, while higher amounts of physical education were not positively or negatively associated with academic achievement among boys.

Useful standards for implementing high-quality, school-based physical activity programs are available from credible sources.119 The nation's public schools are well positioned in their communities to have a dramatic influence on the physical activity and social behavior of youth. Students who have the greatest need to increase physical activity, namely urban minority children and adolescents, have the scantest resources and supports to do so.66,70–72

SUMMARY

  1. Top of page
  2. Abstract
  3. OVERVIEW AND DISPARITIES
  4. CAUSAL PATHWAYS AFFECTING EDUCATIONAL OUTCOMES
  5. WHAT CAN SCHOOLS DO TO INCREASE LEVELS OF PHYSICAL ACTIVITY AND FITNESS?
  6. PROVEN OR PROMISING APPROACHES
  7. SUMMARY
  8. REFERENCES

Strong evidence supports the ability of school-based physical education programs to improve population-wide rates of physical activity and fitness. Benefits of such programs include facilitating physical activity and physical fitness, and favorably affecting weight control and overall health. It seems likely that mental and emotional health may benefit as well. Because physical activity affects the brain and cognition, there are likely to be favorable effects on ability to learn. Further, school-based physical activity programs provide an opportune time to help youth learn and practice social. behaviors associated with teamwork, cooperation, and respect for others, which in turn can favorably influence school climate, connectedness with school, and educational outcomes.

REFERENCES

  1. Top of page
  2. Abstract
  3. OVERVIEW AND DISPARITIES
  4. CAUSAL PATHWAYS AFFECTING EDUCATIONAL OUTCOMES
  5. WHAT CAN SCHOOLS DO TO INCREASE LEVELS OF PHYSICAL ACTIVITY AND FITNESS?
  6. PROVEN OR PROMISING APPROACHES
  7. SUMMARY
  8. REFERENCES
  • 1
    Gordon-Larsen P, Adair LS, Nelson MC, Popkin BM. Five-year obesity incidence in the transition period between adolescence and adulthood: the National Longitudinal Study of Adolescent Health. Am J Clin Nutr. 2004;80:569575.
  • 2
    Kimm SY, Barton BA, Obarzanek E, et al. Racial divergence in adiposity during adolescence: the NHLBI Growth and Health Study. Pediatrics. 2001;107:e34.
  • 3
    Kimm SY, Barton BA, Obarzanek E, et al. Obesity development during adolescence in a biracial cohort: the NHLBI Growth and Health Study. Pediatrics. 2002;110:e54.
  • 4
    Ogden CL, Carroll MD, Flegal KM. High body mass index for age among US children and adolescents, 2003-2006. JAMA. 2008;299:24012405.
  • 5
    Ogden CL, Carroll MD, Curtin LR, McDowell MA, Tabak CJ, Flegal KM. Prevalence of overweight and obesity in the United States, 1999-2004. JAMA. 2006;295:15491555.
  • 6
    Ogden CL, Flegal KM, Carroll MD, Johnson CL. Prevalence and trends in overweight among US children and adolescents, 1999-2000. JAMA. 2002;288:17281733.
  • 7
    Flegal KM, Ogden CL, Carroll MD. Prevalence and trends in overweight in Mexican-American adults and children. Nutr Rev. 2004;62:S144S148.
  • 8
    Freedman DS, Khan LK, Serdula MK, Ogden CL, Dietz WH. Racial and ethnic differences in secular trends for childhood BMI, weight, and height. Obesity (Silver Spring). 2006;14:301308.
  • 9
    Hedley AA, Ogden CL, Johnson CL, Carroll MD, Curtin LR, Flegal KM. Prevalence of overweight and obesity among US children, adolescents, and adults, 1999-2002. JAMA. 2004;291:28472850.
  • 10
    Brown WJ, Burton NW, Rowan PJ. Updating the evidence on physical activity and health in women. Am J Prev Med. 2007;33:404411.
  • 11
    Mora S, Redberg RF, Cui Y, et al. Ability of exercise testing to predict cardiovascular and all-cause death in asymptomatic women: a 20-year follow-up of lipid research clinics prevalence study. JAMA. 2003;290:16001607.
  • 12
    Myers J, Prakash M, Froelicher V, Do D, Partington S, Atwood JE. Exercise capacity and mortality among men referred for exercise testing. New Engl J Med. 2002;346:793801.
  • 13
    Stamatakis E, Hamer M, Primatesta P. Cardiovascular medication, physical activity and mortality: cross-sectional population study with ongoing mortality follow up. Heart. 2008;95:448453.
  • 14
    Bassuk SS, Manson JE. Epidemiological evidence for the role of physical activity in reducing risk of type 2 diabetes and cardiovascular disease. J Appl Physiol. 2005;99:11931204.
  • 15
    Oczkowski W. Complexity of the relation between physical activity and stroke: a meta-analysis. Clin J Sport Med. 2005;15:399.
  • 16
    Wendel-Vos GC, Schuit AJ, Feskens EJ, et al. Physical activity and stroke. A meta-analysis of observational data. Int J Epidemiol. 2004;33:787798.
  • 17
    Chang SC, Ziegler RG, Dunn B, et al. Association of energy intake and energy balance with postmenopausal breast cancer in the prostate, lung, colorectal, and ovarian cancer screening trial. Cancer Epidemiol Biomarkers Prev. 2006;15:334341.
  • 18
    Dallal CM, Sullivan-Halley J, Ross RK, et al. Long-term recreational physical activity and risk of invasive and in situ breast cancer: the California teachers study. Arch Intern Med. 2007;167:408415.
  • 19
    Mai PL, Sullivan-Halley J, Ursin G, et al. Physical activity and colon cancer risk among women in the California Teachers Study. Cancer Epidemiol Biomarkers Prev. 2007;16:517525.
  • 20
    Sprague BL, Trentham-Dietz A, Newcomb PA, Titus-Ernstoff L, Hampton JM, Egan KM. Lifetime recreational and occupational physical activity and risk of in situ and invasive breast cancer. Cancer Epidemiol Biomarkers Prev. 2007;16:236243.
  • 21
    Wolin KY, Lee IM, Colditz GA, Glynn RJ, Fuchs C, Giovannucci E. Leisure-time physical activity patterns and risk of colon cancer in women. Int J Cancer. 2007;121:27762781.
  • 22
    LaMonte MJ, Barlow CE, Jurca R, Kampert JB, Church TS, Blair SN. Cardiorespiratory fitness is inversely associated with the incidence of metabolic syndrome: a prospective study of men and women. Circulation. 2005;112:505512.
  • 23
    Brown WJ, Ford JH, Burton NW, Marshall AL, Dobson AJ. Prospective study of physical activity and depressive symptoms in middle-aged women. Am J Prev Med. 2005;29:265272.
  • 24
    Teychenne M, Ball K, Salmon J. Associations between physical activity and depressive symptoms in women. Int J Behav Nutr Phys Act. 2008;5:27.
  • 25
    Wise LA, Adams-Campbell LL, Palmer JR, Rosenberg L. Leisure time physical activity in relation to depressive symptoms in the Black Women's Health Study. Ann Behav Med. 2006;32:6876.
  • 26
    Blair SN, Kohl HW III, Paffenbarger RS Jr., Clark DG, Cooper KH, Gibbons LW. Physical fitness and all-cause mortality. A prospective study of healthy men and women. JAMA. 1989;262:23952401.
  • 27
    Landi F, Russo A, Cesari M, et al. Walking one hour or more per day prevented mortality among older persons: results from ilSIRENTE study. Prev Med. 2008;47:422442.
  • 28
    Manini TM, Everhart JE, Patel KV, et al. Daily activity energy expenditure and mortality among older adults. JAMA. 2006;296:171179.
  • 29
    Angevaren M, Aufdemkampe G, Verhaar HJ, Aleman A, Vanhees L. Physical activity and enhanced fitness to improve cognitive function in older people without known cognitive impairment. Cochrane Database Syst Rev. 2008;6:CD005381.
  • 30
    Bixby WR, Spalding TW, Haufler AJ, et al. The unique relation of physical activity to executive function in older men and women. Med Sci Sports Exerc. 2007;39:14081416.
  • 31
    Hillman CH, Motl RW, Pontifex MB, et al. Physical activity and cognitive function in a cross-section of younger and older community-dwelling individuals. Health Psychol. 2006;25:678687.
  • 32
    Ortega FB, Ruiz JR, Castillo MJ, Sjöström M. Physical fitness in childhood and adolescence: a powerful marker of health. Int J Obes (Lond). 2008;32:111.
  • 33
    Dencker M, Thorsson O, Karlsson MK, Lindén C, Wollmer P, Andersen LB. Daily physical activity related to aerobic fitness and body fat in an urban sample of children. Scand J Med Sci Sports. 2008;187:728735.
  • 34
    Eisenmann JC, Bartee RT, Smith DT, Welk GJ, Fu Q. Combined influence of physical activity and television viewing on the risk of overweight in U.S. youth. Int J Obes. 2008;32:613618.
  • 35
    Gutin B, Basch CE, Shea S, et al. Blood pressure, fitness and fatness in 5-6 year-old children. JAMA. 1990;264:11231127.
  • 36
    Katzmarzyk PT, Baur LA, Blair SN, Lambert EV, Oppert JM, Riddoch C. Expert panel report from the International Conference on Physical Activity and Obesity in Children, 24-27 June 2007, Toronto, Ontario: summary statement and recommendations. Appl Physiol Nutr Metab. 2008;33:371388.
  • 37
    Lohman TG, Ring K, Pfeiffer K, et al. Relationships among fitness, body composition, and physical activity. Med Sci Sports Exerc. 2008;40:11631170.
  • 38
    Ness AR, Leary SD, Mattocks C, et al. Objectively measured physical activity and fat mass in a large cohort of children. PLoS Med. 2007;4:e97.
  • 39
    Ortega FB, Tresaco B, Ruiz JR, et al. Cardiorespiratory fitness and sedentary activities are associated with adiposity in adolescents. Obesity (Silver Spring). 2007;15:15891599.
  • 40
    Pate RR, Davis MG, Robinson TN, et al. Promoting physical activity in children and youth: a leadership role for schools. A statement from the American Heart Association Council on Nutrition, Physical Activity, and Metabolism (Physical Activity Committee) in collaboration with the Councils on Cardiovascular Disease in the Young and Cardiovascular Nursing. Circulation. 2006;114:12141224.
  • 41
    Treuth MS, Catellier DJ, Schmitz KH, et al. Weekend and weekday patterns of physical activity in overweight and normal-weight adolescent girls. Obesity (Silver Spring). 2007;15:17821788.
  • 42
    Gidding SS, Barton BA, Dorgan JA, et al. Higher self-reported physical activity is associated with lower systolic blood pressure: the Dietary Intervention Study in Children (DISC). Pediatrics. 2006;118:23882393.
  • 43
    Leary SD, Ness AR, Smith GD, et al. Physical activity and blood pressure in childhood: findings from a population based study. Hypertension. 2008;51:9298.
  • 44
    Janz KF, Gilmore JM, Levy SM, Letuchy EM, Burns TL, Beck TJ. Physical activity and femoral neck bone strength during childhood: the Iowa Bone Development Study. Bone. 2007;41:216222.
  • 45
    Sardinha LB, Baptista F, Ekelund U. Objectively measured physical activity and bone strength in 9-year-old boys and girls. Pediatrics. 2008;122:e728e736.
  • 46
    Tobias JH, Steer CD, Mattocks CG, Riddoch C, Ness AR. Habitual levels of physical activity influence bone mass in 11-year-old children from the United Kingdom: findings from a large population based cohort. J Bone Miner Res. 2007;22:101109.
  • 47
    Bonhauser M, Fernandez G, Püschel K, et al. Improving physical fitness and emotional well-being in adolescents of low socioeconomic status in Chile: results of a school based controlled trial. Health Promot Int. 2005;20:113122.
  • 48
    Dishman RK, Hales DP, Pfeiffer KA, et al. Physical self-concept and self-esteem mediate cross-sectional relations of physical activity and sport participation with depression symptoms among adolescent girls. Health Psychol. 2006;25:396407.
  • 49
    Larun L, Nordheim LV, Ekeland E, Hagen KB, Heian F. Exercise in prevention and treatment of anxiety and depression among children and young people. Cochrane Database Syst Rev. 2006;3:CD004691.
  • 50
    Nelson MC, Gordon-Larsen P. Physical activity and sedentary behavior patterns are associated with selected adolescent health risk behaviors. Pediatrics. 2006;117:12811290.
  • 51
    Schmalz DL, Deane GD, Birch LL, Davison KK. A longitudinal assessment of the links between physical activity and self-esteem in early adolescent non-Hispanic females. J Adolesc Health. 2007;41:559565.
  • 52
    Strauss RS, Rodzilsky D, Burack G, Colin M. Psychosocial correlates of physical activity in healthy children. Arch Pediatr Adolesc Med. 2001;155:897902.
  • 53
    Duncan SC, Duncan TE, Strycker LA, Chaumeton NR. A cohort-sequential latent growth model of physical activity from ages 12 to 17. Ann Behav Med. 2007;33:8089.
  • 54
    Eaton DK, Kahn L, Kinchen S, et al. Youth Risk Behavior Surveillance—United States, 2007. MMWR Morb Mortal Wkly Rep. 2008;57:1131.
  • 55
    Kahn JA, Huang B, Gillman MW, et al. Patterns and determinants of physical activity in US adolescents. J Adolesc Health. 2008;42:369377.
  • 56
    McMurray RG, Harrell JS, Creighton D, Wang Z, Bangdiwala SI. Influence of physical activity on change in weight status as children become adolescents. Int J Pediatr Obes. 2008;3:6977.
  • 57
    Hardy LL, Bass SL, Booth ML. Changes in sedentary behaviors among adolescent girls: a 2.5-year prospective study. J Adolesc Health. 2007;40:158165.
  • 58
    Nader PR, Bradley RH, Houts RM, McRitchie SL, O’Brien M. Moderate-to-vigorous physical activity from ages 9 to 15 years. JAMA. 2008;300:295305.
  • 59
    Nelson MC, Neumark-Stzainer D, Hannan PJ, Sirard JR, Story M. Longitudinal and secular trends in physical activity and sedentary behavior during adolescence. Pediatrics. 2006;118:e1627e1634.
  • 60
    Pate RR, Dowda M, O’Neill JR, Ward DS. Change in physical activity participation among adolescent girls from 8th to 12th grade. J Phys Act Health. 2007;4:316.
  • 61
    Pfeiffer KA, Dowda M, Dishman RK, Sirard JR, Pate RR. Physical fitness and performance. Cardiorespiratory fitness in girls-change from middle to high school. Med Sci Sports Exerc. 2007;39:22342241.
  • 62
    Sirard JR, Pfeiffer KA, Dowda M, Pate RR. Race differences in activity, fitness, and BMI in female eighth graders categorized by sports participation status. Pediatr Exerc Sci. 2008;20:198210.
  • 63
    Baker BL, Birch LL, Trost SG, Davison KK. Advanced pubertal status at age 11 and lower physical activity in adolescent girls. J Pediatr. 2007;151:488493.
  • 64
    Davidson KK, Werder JL, Trost SG, Baker BL, Birch LL. Why are early maturing girls less active? Links between pubertal development, psychological well-being, and physical activity among girls at ages 11 and 13. Soc Sci Med. 2007;64:23912404.
  • 65
    Singh GK, Yu SM, Siahpush M, Kogan MD. High levels of physical inactivity and sedentary behaviors among U.S. immigrant children and adolescents. Arch Pediatr Adolesc Med. 2008;162:756763.
  • 66
    Barnett TA, O’Loughlin J, Gauvin L, Paradis G, Hanley J. Opportunities for student physical activity in elementary schools: a cross-sectional survey of frequency and correlates. Health Educ Behav. 2006;33:215322.
  • 67
    Motl RW, Dishman RK, Saunders RP, Dowda M, Pate RR. Perceptions of physical and social environment variables and self-efficacy as correlates of self-reported physical activity among adolescent girls. J Pediatr Psychol. 2007;32:612.
  • 68
    Pate RR, Colabianchi N, Porter D, Almeida MJ, Lobelo F, Dowda M. Physical activity and neighborhood resources in high school girls. Am J Prev Med. 2008;34:413419.
  • 69
    Tucker P, Irwin JD, Gilliland J, He M, Larsen K, Hess P. Environmental influences on physical activity levels in youth. Health & Place. 2009;15:357363.
  • 70
    Gordon-Larsen P, Nelson MC, Page P, Popkin BM. Inequality in the built environment underlies key health disparities in physical activity and obesity. Pediatrics. 2006;117:417424.
  • 71
    Moore LV, Diez Roux AV, Evenson KR, McGinn AP, Brines SJ. Availability of recreational resources in minority and low socioeconomic status areas. Am J Prev Med. 2008;34:1622.
  • 72
    Richmond TK, Hayward RA, Gahagan S, Field AE, Heisler M. Can school income and racial/ethnic composition explain the racial/ethnic disparity in adolescent physical activity participation? Pediatrics. 2006;117:21582166.
  • 73
    Richmond TK, Subramanian SV. School level contextual factors are associated with the weight status of adolescent males and females. Obesity (Silver Spring). 2008;16:13241330.
  • 74
    Ding Q, Vayman S, Akhavan M, Gomez-Pinilla F. Insulin-like growth factor I interfaces with brain-derived neurotropic factor-mediated synaptic plasticity to modulate aspects of exercise-induced cognitive function. Neuroscience. 2006;140:823833.
  • 75
    Coles K, Tomporowski PD. Effects of acute exercise on executive processing, short-term and long-term memory. J Sport Sci. 2008;26:333344.
  • 76
    Deary IJ, Whalley LJ, Batty GD, Starr JM. Physical fitness and lifetime cognitive change. Neurology. 2006;67:11951200.
  • 77
    Sibley BA, Beilock SL. Exercise and working memory: an individual differences investigation. J Sport Exerc Psychol. 2007;29:783791.
  • 78
    Tomporowski PD. Effects of acute bouts of exercise on cognition. Acta Psychologica (Amsterdam). 2003;112:297324.
  • 79
    Kramer AF, Erickson KI, Colcombe SJ. Exercise, cognition, and the aging brain. J Appl Physiol. 2006;101:237242.
  • 80
    Kramer AF, Erickson KI. Capitalizing on cortical plasticity: influence of physical activity on cognition and brain function. Trends Cogn Sci. 2007;11:342348.
  • 81
    Vaynman S, Gomez-Pinilla F. License to run: exercise impacts functional plasticity in the intact and injured central nervous system by using neurotrophins. Neurorehabil Neural Repair. 2005;19:283295.
  • 82
    White LJ, Castellano V. Exercise and brain health—implications for multiple sclerosis: part I—neuronal growth factors. Sports Med. 2008;38:91100.
  • 83
    White LJ, Castellano V. Exercise and brain health—implications for multiple sclerosis: part II—immune factors and stress hormones. Sports Med. 2008;38:176186.
  • 84
    Mahar MT, Murphy SK, Rowe DA, Golden J, Shields AT, Raedeke TD. (2006). Effects of a classroom based program on physical activity and on-task behavior. Med Sci Sports Exerc. 2006;38:20862094.
  • 85
    Etnier JL, Nowell PM, Landers DM, Sibley BA. A meta-regression to examine the relationship between aerobic fitness and cognitive performance. Brain Res Rev. 2006;52:119130.
  • 86
    Hillman CH, Erickson KI, Kramer AF. Be smart, exercise your heart: exercise effects on brain and cognition. Nat Rev Neurosci. 2008;9:5865.
  • 87
    Vaynman S, Gomez-Pinilla F. Revenge of the “sit”: how lifestyle impacts neuronal and cognitive health through molecular systems that interface energy metabolism with neuronal plasticity. J Neurosci Res. 2006;84:699715.
  • 88
    Ploughman M. Exercise is brain food: the effects of physical activity on cognitive function. Dev Neurorehabil. 2008;11:236240.
  • 89
    Caterino MC, Polak ED. Effects of two types of activity on the performance of second-, third-, and fourth-grade students on a test of concentration. Percept Mot Skills. 1999;89:245248.
  • 90
    Ahamed Y, Macdonald H, Reed K, Naylor PJ, Liu-Ambrose T, McKay H. School-based physical activity does not compromise children's academic performance. Med Sci Sports Exerc. 2007;39:371376.
  • 91
    Coe DP, Pivarnik JM, Womack CJ, Reeves MJ, Malina RM. Effect of physical education and activity levels on academic achievement in children. Med Sci Sports Exerc. 2006;38:15151519.
  • 92
    Sallis JF, McKenzie TL, Kolody B, Lewis M, Marshall S, Rosengard P. Effects of health-related physical education on academic achievement: Project SPARK. Res Q Exerc Sport. 1999;70:127134.
  • 93
    Carlson SA, Fulton JE, Lee SM, et al. Physical education and academic achievement in elementary school: data from the Early Childhood Longitudinal Study. Am J Public Health. 2008;98:721727.
  • 94
    Castelli DM, Hillman CH, Buck SM, Erwin HE. Physical fitness and academic achievement in third- and fifth-grade students. J Sport Exerc Psychol. 2007;29:239252.
  • 95
    Hillman CH, Castelli DM, Buck SM. Aerobic fitness and neurocognitive function in healthy preadolescent children. Med Sci Sports Exerc. 2005;37:19671974.
  • 96
    Buck SM, Hillman CH, Castelli DM. The relation of aerobic fitness to stop task performance in preadolescent children. Med Sci Sports Exerc. 2008;40:166172.
  • 97
    Taras H. Physical activity and student performance. J Sch Health. 2005;75:214218.
  • 98
    Sibley BA, Etnier JL. The relationship between physical activity and cognition in children: a meta-analysis. Pediatr Exerc Sci. 2003;15:243256.
  • 99
    Trudeau F, Shepard RJ. Physical education, school physical activity, sports and academic performance. Int J Behav Nutr Phys Act. 2008;5:10.
  • 100
    Ge X, Conger RD, Elder GH Jr. Pubertal transition, stressful life events, and the emergence of gender differences in adolescent depressive symptoms. Dev Psychol. 2001;37:404417.
  • 101
    Kessler RC, Avenevoli S, Ries Merikangas K. Mood disorders in children and adolescents: an epidemiologic perspective. Biol Psychiatry. 2001;49:10021014.
  • 102
    Patton GC, Hemphill SA, Beyers JM, et al. Pubertal stage and deliberate self-harm in adolescents. J Am Acad Child Adolesc Psychiatry. 2007;46:508514.
  • 103
    Patton GC, Viner R. Pubertal transitions in health. Lancet. 2007;369:11301139.
  • 104
    Bond L, Butler H, Thomas L, et al. Social and school connectedness in early secondary school as predictors of late teenage substance use, mental health, and academic outcomes. J Adolesc Health. 2007;40:357.e9e18.
  • 105
    Rice M, Kang DH, Weaver M, Howell CC. Relationship of anger, stress, and coping with school connectedness in fourth-grade children. J Sch Health. 2008;78:149156.
  • 106
    Shochet IM, Dadds MR, Ham D, Montague R. School connectedness is an underemphasized parameter in adolescent mental health: results of a community prediction study. J Clin Child Adolesc Psychol. 2006;35:170179.
  • 107
    Geier AB, Foster GD, Womble LG, et al. The relationship between relative weight and school attendance among elementary schoolchildren. Obesity. 2007;15:21572163.
  • 108
    Shore SM, Sachs ML, Lidicker JR, Brett SN, Wright AR, Libonati JR. Decreased scholastic achievement in overweight middle school students. Obesity. 2008;16:15351538.
  • 109
    Fitch KD, Morton AR, Blanksby BA. Effects of swimming training on children with asthma. Arch Dis Child. 1976;51:190194.
  • 110
    Matsumoto I, Araki H, Tsuda K, et al. Effects of swimming training on aerobic capacity and exercise induced bronchoconstriction in children with bronchial asthma. Thorax. 1999;54:196201.
  • 111
    Ram FS, Robinson SM, Black PN, Picot J. Physical training for asthma. Cochrane Database Syst Rev. 2005;4:CD001116.
  • 112
    Welsh L, Kemp JG, Roberts RG. Effects of physical conditioning on children and adolescents with asthma. Sports Med. 2005;35:127141.
  • 113
    Bonsignore MR, La Grutta S, Cibella F. Effects of exercise training and montelukast in children with mild asthma. Med Sci Sports Exerc. 2008;40:405412.
  • 114
    Fanelli A, Cabral AL, Neder JA, Martins MA, Cavalho CR. Exercise training on disease control and quality of life in asthmatic children. Med Sci Sports Exerc. 2007;39:14741480.
  • 115
    Basaran S, Guler-Uysal F, Ergen N, Seydaoglu G, Bingol-Karakoç G, Ufuk Altintas D. Effects of physical exercise on quality of life, exercise capacity and pulmonary function in children with asthma. J Rehabil Med. 2006;38:130135.
  • 116
    Williams B, Powell A, Hoskins G, Neville R. Exploring and explaining low participation in physical activity among children and young people with asthma: a review. BMC Fam Pract. 2008;9:40.
  • 117
    Yin Z, Moore JB. Reexamining the role of interscholastic sport participation in education. Psychol Rep. 2004;94:14471454.
  • 118
    Centers for Disease Control and Prevention. Guidelines for school and community programs to promote lifelong physical activity among young people. MMWR Morb Mortal Wkly Rep. 1997;46(RR-6): 142.
  • 119
    National Association for Sport and Physical Education. Moving Into the Future: National Standards for Physical Education. 2nd ed. Reston, VA: Author; 2004.
  • 120
    Pate RR, Wang CY, Dowda M, Farrell SW, O’Neill JR. Cardiorespiratory fitness levels among US youth 12 to 19 years of age: findings from the 1999-2002 National Health and Nutrition Examination Survey. Arch Pediatr Adolesc Med. 2006;160:10051012.
  • 121
    Pate RR, O’Neill JR. Summary of the American Heart Association scientific statement: promoting physical activity in children and youth: a leadership role for schools. J Cardiovasc Nurs. 2008;23:4449.
  • 122
    Strong WB, Malina RM, Blimkie CJ, et al. Evidence based physical activity for school-age youth. J Pediatr. 2005;146:732737.
  • 123
    Task Force on Community Preventive Services. Guide to community preventive services. Enhanced physical education classes are recommended to increase physical activity among young people. Available at: http://www.thecommunityguide.org/pa/behavioral-social/schoolbased-pe.html. Accessed October 17, 2008.
  • 124
    Centers for Disease Control and Prevention. A report on recommendation of the Task Force on Community Preventive Services. MMWR Morb Mortal Wkly Rep. 2001;50: 116.
  • 125
    Ginsburg KR, American Academy of Pediatrics Committee on Communications, & American Academy of Pediatrics Committee on Psychosocial Aspects of Child and Family Health. The importance of play in promoting healthy child development and maintaining strong parent-child bonds. Pediatrics. 2007;119:182191.
  • 126
    Barr-Anderson DJ, Young DR, Sallis JF, et al. Structured physical activity and psychosocial correlates in middle-school girls. Prev Med. 2007;44:404409.
  • 127
    Barr-Anderson DJ, Neumark-Sztainer D, Schmitz KH, et al. But I like PE: factors associated with enjoyment of physical education class in middle school girls. Res Q Exerc Sport. 2008;79:1827.
  • 128
    Dishman RK, Motl RW, Saunders R, et al. Enjoyment mediates effects of a school-based physical-activity intervention. Med Sci Sports Exerc. 2005;37:478487.
  • 129
    Gordon-Larsen P, McMurray RG, Popkin BM. Determinants of adolescent physical activity and inactivity patterns. Pediatrics. 2000;105:E83.
  • 130
    Molnar BE, Gortmaker SL, Bull FC, Buka SL. Unsafe to play? Neighborhood and lack of safety predict reduced physical activity among urban children and adolescents. Am J Health Promot. 2004;18:378386.
  • 131
    Richmond TK, Field AE, Rich M. Can neighborhoods explain racial/ethnic differences in adolescent inactivity? Int J Pediatr Obes. 2007;2:202210.
  • 132
    Ries AV, Gittelson J, Voorhees CC, Roche KM, Clifton KJ, Astone NA. The environment and urban adolescents use of recreational facilities for physical activity. Am J Health Promot. 2008;23:4350.
  • 133
    Dishman RK, Saunders RP, Motl RW, Dowda M, Pate RR. Self-efficacy moderates the relation between declines in physical activity and perceived social support in high school girls. J Pediatr Psychol. 2009;34:441451.
  • 134
    Ridgers ND, Stratton G, Fairclough SJ. Physical activity levels of children during school playtime. Sports Med. 2006;36:359371.
  • 135
    Stratton G, Ridgers ND, Fairclough SJ, Richardson DJ. Physical activity levels of normal-weight and overweight girls and boys during primary school recess. Obesity. 2007;15:15131519.
  • 136
    Davidson KK, Werder JL, Lawson CT. Children's active commuting to school: current knowledge and future directions. Prev Chronic Dis. 2008;5:A100.
  • 137
    Centers for Disease Control and Prevention. Barriers to children walking and biking to school—United States, 1999. MMWR Morb Mortal Wkly Rep. 2002;51:701704.
  • 138
    Centers for Disease Control and Prevention. Barriers to children walking to or from school—United States, 2004. MMWR Morb Mortal Wkly Rep. 2005;54:949952.
  • 139
    Ham SA, Martin S, Kohl HW. Changes in the percentage of students who walk or bike to school—United States, 1969 and 2001. J Phys Act Health. 2008;5:205215.
  • 140
    McDonald NC. Active transportation to school: trends among U.S. school children, 1969-2001. Am J Prev Med. 2007;32:509516.
  • 141
    McDonald NC. Critical factors for active transportation to school among low-income and minority students. Evidence from the 2001 National Household Travel Survey. Am J Prev Med. 2008;34:341344.
  • 142
    Centers for Disease Control and Prevention. Kidswalk-to-school. Available at: http://www.cdc.gov/nccdphp/Dnpa/kidswalk. Accessed December 27, 2008.
  • 143
    National Center for Safe Routes to Schools. Saferoutes. Available at: http://www.saferoutesinfo.org. Accessed December 27, 2008.
  • 144
    Stewart JA, Dennison DA, Kohl HW, Doyle JA. Exercise level and energy expenditure in the TAKE 10! in-class physical activity program. J Sch Health. 2004;74:397400.
  • 145
    Honas JJ, Washburn RA, Smith BK, Greene JL, Donnelly JE. Energy expenditure of the physical activity across the curriculum intervention. Med Sci Sports Exerc. 2008;40:15011505.
  • 146
    Pate RR, Saunders R, Dishman RK, Addy C, Dowda M, Ward DS. Long-term effects of a physical activity intervention in high school girls. Am J Prev Med. 2007;33:276280.
  • 147
    Pate RR, Ward DS, O’Neill JR, Dowda M. Enrollment in physical education is associated with overall physical activity in adolescent girls. Res Q Exerc Sport. 2007;78:265270.
  • 148
    Pate RR, Ward DS, Saunders RP, Felton G, Dishman RK, Dowda M. Promotion of physical activity among high-school girls: a randomized controlled trial. Am J Public Health. 2005;95:15821587.
  • 149
    Pfeiffer KA, Dowda M, Dishman RK, et al. Sport participation and physical activity in adolescent females across a four-year period. J Adolesc Health. 2006;39:523529.
  • 150
    Saunders RP, Ward D, Felton GM, Dowda M, Pate RR. Examining the link between program implementation and behavior outcomes in the Lifestyle Education for Activity Program (LEAP). Eval Program Plann. 2006;29:352364.
  • 151
    Ward DS, Saunders R, Felton GM, Williams E, Epping JN, Pate RR. Implementation of a school environment intervention to increase physical activity in high school girls. Health Educ Res. 2006;21:896910.