Educational paper literature review 3

Journal of Psychosomatic Res

Relations of physical self-concept and self-efficacy with frequency of

voluntary physical activity in preadolescents:

Implications for after-school care programming

James J. Annesi4

YMCA of Metropolitan Atlanta, 100 Edgewood Avenue, N.E., Suite 1100, Atlanta, GA 30303, USA

Received 23 November 2005

Abstract

Objective: This study aimed to test relations of physical self-

concept and self-efficacy with voluntary physical activity in

preadolescents enrolled in an after-school physical activity pro-

gram. Methods: Participants in the 2003 (n =41) and 2005 (n =84)

versions of the Youth Fit For Life protocol and the control group

(n =40) completed the Physical Self-Concept scale, the Exercise

Barriers Self-Efficacy Scale for Children, and a recall of physical

activity frequency at Weeks 1 and 12. Results: Both treatment

groups demonstrated significantly increased frequency of voluntary

physical activity over 12 weeks. The 2005 version additionally

demonstrated significant improvements in both physical self-

0022-3999/06/$ – see front matter D 2006 Elsevier Inc. All rights reserved.

doi:10.1016/j.jpsychores.2006.04.009

4 Tel.: +1 404 267 5355; fax: +1 404 527 7693.

E-mail address: [email protected].

concept and exercise barriers self-efficacy. Within the treatment

groups, significant correlations between changes in physical self-

concept and self-efficacy and physical activity sessions completed

were found. Multiple regression indicated that 7% to 28% of the

variance in voluntary physical activity was explained by the

simultaneous entry of changes in physical self-concept and self-

efficacy. Conclusion: Tenets of social cognitive and self-efficacy

theory were supported and suggested that curricular elements of

after-school care programming may increase overall outputs of

moderate-to-vigorous physical activity in preadolescents.

D 2006 Elsevier Inc. All rights reserved.

Keywords: After-school care; Exercise; Physical activity; Physical self-concept; Preadolescents; Self-efficacy

Introduction

Considering race and sex, 12% to 22% of preadolescent

American children are overweight based on growth charts

for the year 2000 [1]. This represents a threefold increase

over the last 25 years. Overweight in children and

adolescents is a major predictor of early onset of Type II

diabetes mellitus and obesity throughout the life span [2].

Along with a diet high in fat and kilocalories, lack of

physical activity has been linked to the increasing concerns

for children’s weight [2–4]. It has been suggested that

schools play a large part in fostering positive health

behaviors in children. Physical education (PE) however, is

currently being reduced in many U.S. schools [5]. For many

school administrators, priorities for PE are low compared

with academic subjects. Increasingly, PE is being conducted

by nonspecialists; however, even when conducted by PE

professionals, only 10% to 36% of class time is spent in

moderate-to-vigorous activity [6,7]. An average of 12% less

time active was demonstrated with non-PE specialists [8].

Based on goals set by the U.S. Department of Health and

Human Services [9], methods for supporting needed

amounts of physical activity for children have been lacking.

Interventions focusing on improving the quantity and quality

of physical activity have primarily been school based and

have had mixed results (see Ref. [10], for a review). Re-

searchers have suggested that the nearly exclusive focus on

during-school PE is misplaced [11]; however, research has

not generally attended to other settings. Compared with

advocacy for increased PE time, which has not been

successful [5], less attention has been given to the role of

earch 61 (2006) 515–520

J.J. Annesi / Journal of Psychosomatic Research 61 (2006) 515–520516

after-school care in providing and fostering increased

physical activity and other health behaviors. Approximately

6.5 million children attend after-school care in the United

States, with a demand of approximately 22 million [12].

Possibly, factors associated with increases in freely

chosen physical activities may also be positively affected

through specifically designed curricular elements. Cumu-

lative effects would be likely to have added health benefits.

Based on primary tenets of social cognitive theory and self-

efficacy theory [13–15] and supported by most, but not all,

related studies of children (see Refs. [16,17], for reviews),

the two factors of self-regulatory efficacy and task self-

efficacy may be of high concern when developing curricula

with a focus on increasing both program-based, moderate-

to-vigorous physical activity and physical activity chosen

during free time. Self-regulatory efficacy refers to individ-

uals’ ability to utilize internal resources and persevere at a

behavior (here, physical activity) in spite of impediments or

challenges. It is thought that development or improve-

ment of one’s self-management and self-regulatory abilities

would allow individuals to overcome personal and environ-

mental barriers and thus demonstrate improved persistence.

If, for example, behavioral skills such as goal setting,

productive self-talk, and recruitment of social support are

incorporated into physical activity instruction, they may

help to develop conditions where moderate-to-vigorous

physical activity behaviors bgeneralizeQ into out-of-school choices through increased motivation, effort, and persis-

tence [18–20]. The inclusion of behavioral skills in physical

activity programming for children has previously been

recommended [9]. Task self-efficacy refers to individuals’

assessment of their own physical abilities to carry out a task.

It is thought that success at a physically challenging task

increases one’s confidence for the future. If physical

activities are presented in a nonthreatening manner, where

physical challenges approximate abilities, an increase in

physical self-concept may lead to physical activity being

more frequently chosen outside of programmed settings

because of associated feelings of mastery.

Youth Fit For Life is a physical activity protocol con-

ducted during after-school care. Preliminary results indicate

its association with improvements in physical [21] and

mental [22] health factors. The present investigation

assesses Youth Fit For Life for its association with changes

in measures of task and self-regulatory efficacy and their

association with frequency of freely chosen physical activity

in preadolescents. Because preliminary testing indicated that

self-regulatory efficacy was significantly related to

increased out-of-school activity, a more recent version of

the protocol (i.e., 2005) extended curricular elements around

self-management and self-regulatory skills. It was hypothe-

sized that:

1. Within the Youth Fit For Life treatment groups,

assessments of task self-efficacy (i.e., physical self-

concept), self-regulatory self-efficacy (i.e., exercise

barriers self-efficacy), and weekly frequency of

physical activity sessions completed outside of PE

and after-school programming would significantly

increase over the 12-week program.

2. The 2005 treatment group would demonstrate

greater increase on exercise barriers self-efficacy

and frequency of self-selected physical activity than

the 2003 treatment group.

3. Changes in physical self-concept and exercise bar-

riers self-efficacy would be significantly correlated to

weekly frequency of voluntary physical activity.

4. A significant amount of the variance in voluntary,

weekly physical activity would be accounted for

by simultaneous inclusion of changes in physical

self-concept and exercise barriers self-efficacy as

predictors.

It was hoped that findings would contribute to ongoing

refinements of after-school care curricula so that important

factors for increasing children’s overall physical activity

behavior may be best accommodated.

Method

Participants

Participants were recruited from a YMCA-based after-

school care system in the southeastern United States.

Individuals with incomplete data sets were excluded. No

statistically significant ( P valuesN.05) difference was found

between the 2003 treatment group (n =41), 2005 treatment

group (n =84), and control group (n =40) on sex ratio

(overall, 64% were female), ethnic grouping (overall, 70%

were African American, 19% Caucasian, 11% from other

ethnic groups), age (overall, range was between 9 and

12 years, M=10.8, S.D.=1.1), and body mass index [weight

(kilograms)/height (meters squared); overall, M =19.4,

S.D.=2.6]. The sample size of the 2003 treatment and

control groups was reduced due to problems with an elec-

tronic scoring system. Informed consent was obtained from

a parent or caregiver.

Measures

Physical self-concept

The Physical Self-Concept subscale of the Tennessee

Self-Concept Scale: 2 Child Form [23] is a self-report

instrument intended for use with children aged 7 through

14 years. Although only a single score is recorded from

responses ranging from 1 (always false) to 5 (always true)

on 12 items, item clusters include identity (e.g., My body is

healthy), satisfaction (e.g., I’d like to change some part of

my body), and behavior (e.g., I’m not good at sports and

games). Factor analysis supported the Physical Self-Concept

subscale items relative to the other five subscales of the

J.J. Annesi / Journal of Psychosomatic Research 61 (2006) 515–520 517

Tennessee Self-Concept Scale: 2 Child Form. Internal con-

sistency for the 9- to 12-year-old age group averaged .70,

and test–retest reliability over 1 week was .71 [23]. Seven of

the 12 items had negative wording. Possible scores ranged

from 12 to 60. Within this investigation, physical self-

concept related to the construct of task self-efficacy within

self-efficacy theory.

Exercise barriers self-efficacy

The Exercise Barriers Self-Efficacy Scale for Children

[21] is a self-report instrument intended to assess exercise

barriers self-efficacy or the degree one believes he or she

possesses the ability to overcome social, personal, and

environmental barriers to participating in exercise. Con-

struction of the 10-item inventory, with each item beginning

with the stem, bI am sure I can exercise three or more days per week even if . . .,Q was based on previous research [24–26] and adapted to be appropriate for ages 9 through

12 years. Sample items were, bI was nervous being around other peopleQ (social barrier), bI felt physically uncomfort- able while exercisingQ (personal barrier), and bThe weather was bad (very hot, rainy, very cold)Q (environmental barrier). Internal consistency for the 9- to 12-year-old age

group averaged .79, and test–retest reliability over 1 week

was .77 [21]. Responses ranged from 1 (not at all confident)

to 5 (definitely confident). Possible scores ranged from 10 to

50. Within this investigation, exercise barriers self-efficacy

related to the construct of self-regulatory efficacy within

self-efficacy theory.

Physical activity frequency

A single item was used to assess the number of days a

participant completed a moderate-to-vigorous (bmade you breathe harder than usualQ) session of physical activity or exercise over the previous week, excluding such physical

activities completed during school (e.g., PE class) or

programming associated with after-school care. The item

was based on review of the extant physical activity recall

research (see Ref. [27]) and adapted from recent research

with 12-year-olds from Canada [28]. Test–retest reliability

over 1 week was .79. The correlation between recalled days

of self-selected moderate-to-vigorous physical activity and

time to complete a 1-mile (1.61 km) run/walk (a measure of

cardiorespiratory fitness) was significant, r=�.39, Pb.01. Possible responses ranged from 0 to 7.

Changes on each measure were derived by subtracting

scores at Week 1 from scores at Week 12.

Procedure

All participants were enrolled in a 12-week segment of

after-school care. The participant-to-counselor ratio was

approximately 15:1. In addition to completion of home-

work, study, receiving tutoring, and consuming a snack,

physical activity time was provided to all three groups under

study within school multipurpose rooms or recreation

areas. In the 2003 treatment group, the original Youth Fit

For Life curriculum was administered by after-school

counselors and supported periodically (once every 2 weeks)

by the YMCA wellness staff. The 2003 Youth Fit For

Life treatment consisted of 3 days/week at 45 min/session.

It included cardiovascular activities in the form of non-

competitive games and tasks each day for 20 min. Two days

per week resistance training, utilizing age-appropriate

resistance bands for 20 min, was administered. An overview

of basic self-management/self-regulatory skills (e.g., goal

setting, self-monitoring, self-talk/cognitive restructuring,

recruiting social support) was provided 1 day/week for

20 min in a conversational group format. General health and

nutrition information was also provided to participants (one

theme per week, e.g., bFruits and Vegetables,Q bHeart Health,Q bFast FoodsQ) for 5 min/day. Every effort was made to make activities as nonthreatening as possible while

challenging participants to seek self-improvement.

The 2005 treatment group maintained a similar curricu-

lum; however, the self-management/self-regulatory compo-

nent was extended. A more detailed guide on this component

was provided to the after-school counselors administering

Youth Fit For Life. Additionally, a workbook, tailored for

the present age range, was used by the participants in an

effort to better train the self-management/self-regulatory

skills. For example, a walking path analogy, with graphics

annotating progress toward a bFinish Line,Q was incorpo- rated to support goal setting and self-monitoring of progress.

Self-talk and cognitive restructuring were supported through

the workbook, calling for participants to write down bmeanQ statements spoken internally and reframing them by

b. . . talking to yourself like you are your own best friend.Q Volunteers were recruited to share their responses in a

group format to facilitate discussion. Some of the work-

book activities required participants’ attention outside of

program time. A quality assessment form administered by

the supporting YMCA wellness staff also more fully

addressed participants’ adoption of the self-management/

self-regulatory skills. More complete treatment descriptions

may be found elsewhere [21] or will be provided by the

author upon request.

The control group’s physical activity component was

largely unstructured and voluntary. Children were free to

participate in physical activities of their own choosing for

30 to 45 min. The role of the after-school counselor was

primarily to ensure safety. No details were given to par-

ticipants and caregivers on the physical activity components

before the start of the program. Data were collected on a

12-week time frame beginning in January 2003 for the

treatment group and control group and beginning January

2005 for the 2005 treatment group.

Before the start and at the end of their 12-week after-

school program, children from each group completed the

Physical Self-Concept scale, the Exercise Barriers

Self-Efficacy Scale for Children, and recalled number of

Table 1

Changes in physical self-concept, self-efficacy, and weekly physical activity frequency over 12 weeks

Scale

Week 1 Week 12

t df P dM S.D. M S.D.

2003 Treatment (n=41)

Physical self-concept 34.39 4.50 35.80 5.83 1.80 40 .080 .31

Exercise barriers self-efficacy 27.90 6.48 28.49 9.16 0.56 40 .579 .09

Physical activity frequency/week 2.39 1.24 3.24 1.26 4.93 40 b.001 .69

2005 Treatment (n=84)

Physical self-concept 34.22 5.28 35.38 6.06 2.55 83 .013 .22

Exercise barriers self-efficacy 27.92 9.32 29.80 9.35 3.94 83 b.001 .20

Physical activity frequency/week 2.18 2.03 3.42 2.05 5.62 83 b.001 .61

Control (n=40)

Physical self-concept 34.67 4.99 35.47 6.10 0.93 39 .358 .16

Exercise barriers self-efficacy 27.50 8.25 27.60 8.16 0.14 39 .889 .01

Physical activity frequency/week 2.25 2.21 2.46 2.18 1.07 39 .291 .10

Note. Physical Self-Concept is a subscale of the Tennessee Self-Concept Scale: 2 Child Form. Exercise Barriers Self-Efficacy is derived from the Exercise

Barriers Self-Efficacy Scale for Children. Physical activity frequency/week denotes recalled number of moderate-to-vigorous physical activity sessions

(excluding in-school PE and after-school programming) completed over the previous week.

J.J. Annesi / Journal of Psychosomatic Research 61 (2006) 515–520518

moderate-to-vigorous physical activity sessions completed

in the previous week (excluding PE and after-school

programming) in a private area. Compliance with the

established Youth Fit For Life protocol by the counselors

was assessed through a 25-item audit form completed by

both the YMCA wellness staff and study administrators at

five times through the 12-week program. Those administer-

ing audits received training. Interrater reliability was N.90. If

a score of less then 100 (out of a possible 125) on the audit

occurred, corrective action was taken by a study admin-

istrator with a supervisor of the after-school counselors.

Follow-up discussions and supplemental training by super-

visors to counselors were generally successful based on

subsequent improvements in their audit scores. The overall

quality of program administration was thus judged sufficient

by the principal investigator to retain all collected data.

Table 2

Linear bivariate correlations between changes over 12 weeks in physical

self-concept, self-efficacy, and weekly physical activity frequency for the

2003 treatment group

Scale 1 2 3 4

1. D TSCS physical self-concept – .296 .3914 .094

2. D Exercise barriers self-efficacy – .45244 .3214

3. D Physical activity frequency/week – �.43144 4. Physical activity frequency at Week 12 –

Note. Physical Self-Concept is a subscale of the Tennessee Self-Concept

Scale: 2 Child Form (TSCS). Exercise Barriers Self-Efficacy is derived

from the Exercise Barriers Self-Efficacy Scale for Children. Physical

activity frequency/week denotes recalled number of moderate-to-vigorous

physical activity sessions (excluding in-school PE and after-school

programming) completed over the previous week. The Delta symbol (D)

denotes change in the corresponding measure from Week 1 to Week 12.

4 Pb.05.

44 Pb.01.

Results

Statistical significance was set at a =.05 (two tailed) throughout. Due to the exploratory nature of the inves-

tigation and hypotheses derived from established theory, no

adjustment was made for multiple tests [29]. No statistically

significant difference ( P valuesN.05) was found in Physical

Self-Concept scores, Exercise Barriers Self-Efficacy scores,

and reported days physically active per week at the end of

the program between girls and boys in any group, nor was

there any statistically significant change from the start to the

end of the program between the said samples. Data were

therefore pooled for further analyses.

Within-group changes over 12 weeks

Dependent t tests were conducted to determine if

statistically significant changes in Physical Self-Concept

scores, Exercise Barriers Self-Efficacy scores, and reported

days physically active per week occurred over the 12-week

investigation by group (see Table 1). Significant improve-

ments in Physical Self-Concept and Exercise Barriers Self-

Efficacy scores were found for the 2005 treatment group

only. Significant increases in reported days physically active

per week were found for both the 2005 and 2003 treatment

groups. No significant changes were found for the control

group. Where a statistically significant change was found in

more than one group, means were contrasted. The change in

days of physical activity completed per week reported by

the 2005 treatment group (Mchange=1.25, S.D.=1.14) was

significantly greater than the 2003 treatment group

(Mchange=0.85, S.D.=1.01), t(123)=2.00, P=.048, d=.36.

Relations of changes in self-concept and self-efficacy with

physical activity

Further analyses of the Youth Fit For Life treatment groups

only indicated significant linear bivariate correlations

between changes over 12 weeks in Exercise Barriers Self-

Efficacy scores and changes in both reported physical

Table 3

Linear bivariate correlations between changes over 12 weeks in physical

self-concept, self-efficacy, and weekly physical activity frequency for the

2005 treatment group

Scale 1 2 3 4

1. D Physical self-concept – .29544 .2614 .208

2. D Self-efficacy – .2484 .2244

3. D Physical activity frequency – �.43744 4. Physical activity frequency at Week 12 –

Note. Physical Self-Concept is a subscale of the Tennessee Self-Concept

Scale: 2 Child Form. Exercise Barriers Self-Efficacy is derived from the

Exercise Barriers Self-Efficacy Scale for Children. Physical activity

frequency/week denotes recalled number of moderate-to-vigorous physical

activity sessions (excluding in-school PE and after-school programming)

completed over the previous week. The Delta symbol (D) denotes change in

the corresponding measure from Week 1 to Week 12.

4 Pb.05.

44 Pb.01.

J.J. Annesi / Journal of Psychosomatic Research 61 (2006) 515–520 519

activity session frequency per week and weekly physical

activity frequency at the end of the program (Week 12)

for both the 2003 and 2005 treatment groups (see Tables 2

and 3). Significant bivariate correlations between changes

over 12 weeks in Physical Self-Concept scores and changes

in physical activity frequency per week were found for both

the 2003 and 2005 treatment groups. However, correlations

between Physical Self-Concept score changes and reported

weekly physical activity frequency at Week 12 did not

reach statistical significance for either treatment group (see

Tables 2 and 3).

Finally, four separate multiple linear regression analyses,

with simultaneous entry of independent variables, were

conducted. For the 2003 treatment group, entry of changes

in both Exercise Barriers Self-Efficacy and Physical Self-

Concept scores accounted for a statistically significant 28%

of the variance in changes in reported weekly physical

activity frequency, R 2 =.28, F(2, 38)=7.29, P=.002. Entry

of the same independent variables into another regression

equation explained a nonsignificant 10% of the variance in

physical activity frequency at Week 12, R 2 =.10, F(2,

38)=2.18, P=.127. For the 2005 treatment group, entry of

changes in both Exercise Barriers Self-Efficacy and Physical

Self-Concept scores accounted for a statistically significant

10% of the variance in changes in reported weekly physical

activity frequency, R 2 =.10, F(2, 81)=4.50, P=.014. Entry

of the same independent variables into another regression

equation explained a significant 7% of the variance in

physical activity frequency at Week 12, R 2 =.07, F(2,

81)=3.16, P=.048.

Discussion

Findings from the present preliminary investigation

indicated that the Youth Fit For Life physical activity

protocol was associated with significant increases in free-

time physical activity in the preadolescent after-school

participants tested. Comparable studies on after-school

physical activity programs were not found. Possibly because

of curriculum improvements, the 2005 version of Youth Fit

For Life was also associated with significant increases in

physical self-concept and exercise-related self-efficacy

over 12 weeks, as well as a significantly greater increase

in voluntary exercise frequency compared with the 2003

version of the protocol. The improvements in self-manage-

ment and self-regulatory skills training methods, however,

would have predicted greater effect on exercise barriers self-

efficacy only (along with the associated improvement in

physical activity frequency already noted). For both the

2003 and 2005 treatment groups, correlational analyses

indicated that changes over 12 weeks in both physical self-

concept and self-efficacy were significantly related to

changes in voluntary physical activity over the same time.

Only changes in exercise barriers self-efficacy was signifi-

cantly correlated to frequency of physical activity at the end

of the program, however.

Based on self-efficacy theory [14], it was assumed that

physical self-concept was consistent with task self-efficacy

(perceiving the physical capability to carry out the task), and

exercise barriers self-efficacy was consistent with self-

regulatory self-efficacy (perceiving the psychological/voli-

tional capability to carry out the task). Following these

distinctions, it was partially supported that improvements in

both physical self-concept and exercise barriers self-efficacy

would be related to freely chosen physical activity. Tenets

of self-efficacy theory were further supported by findings

indicating that changes in the two aforementioned constructs

demonstrated positive, small-to-moderate associations with

each other (r values=.295 and .296). This suggested that

each may be related to bglobalQ self-efficacy but distinct enough to warrant separate inclusion in the model and,

hence, the present study. Further, regression analyses indi-

cated that simultaneous entry of changes in both physical

self-concept and exercise barriers self-efficacy explained a

significant 10% and 28% of the variance in changes in

physical activity over 12 weeks, respectively. This further

indicated that the inclusion of the two types of self-efficacy,

together, had useful predictive properties for physical

activity behavior change in preadolescents. It also suggested

that intervention design should seek curricular elements to

reliably improve each—especially where physical activity

does not meet recommended amounts. That being stated, it

is also acknowledged that the predictive value of the

constructs tested on frequency of voluntary exercise was

only minimal to moderate, suggesting that extension of this

research is needed.

Although the present study had limitations such as a

brief time frame, specific sample, and field design, it was

able to report on applied intervention research, addressing

the topic of reduced physical activity in children. Extensions

of this research will require follow-up assessment to esti-

mate retention of physical activity changes and additional

measures (e.g., parents’ reports) to confirm accuracy of self-

reported physical activity. Replication across ages, ethnic

J.J. Annesi / Journal of Psychosomatic Research 61 (2006) 515–520520

groupings, and socioeconomic strata will be required for

increased confidence and for the ability to generalize results.

Because PE may not be able to rapidly change in a manner

that facilitates significant improvements in children’s

physical activity and other health behaviors, alternate

methods are warranted. Efficient use of existing resources

and opportunities will be critical [4,30].

In summary, this investigation suggests that Youth Fit

For Life, a physical activity protocol designed for wide-

spread dissemination by after-school staff with little or no

previous training in PE or health behavior change methods,

may not only improve physical health and psychological

factors over the short term but also induce increased

physical activity behavior outside the formally programmed

time. This may be an important factor for overall health

improvement in children, over time. Within this research,

the use of established theory allowed for purposeful

modifications and extensions of existing protocol compo-

nents. Ongoing testing of treatment effects, which follows

from this, will hopefully serve to continue to aid in

improved health outcomes. It will require better manipu-

lation of within-school, after-school, and outside-the-school

conditions to effectively change physical outputs of children

and reduce pathologies associated with inactivity. Continued

research into effective administration of evidence-based

physical activity programming and health behavior change

and firm commitments from parents, educators, medical

professionals, policymakers, and the general public are

required to reverse obesity trends in children.

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