Availability of sports facilities as moderator of the intention–sports participation relationship among adolescents
Availability of sports facilities as moderator of the intention-sports participation relationship among adolescents
Richard G. Prins 0 3
Pepijn van Empelen 0 3
Saskia J. te Velde 1 3
Anna Timperio 2 3
Frank J. van Lenthe 0 3
Nannah I. Tak 1 3
David Crawford 2 3
Johannes Brug 1 3
Anke Oenema 0 3
0 Department of Public Health, Erasmus University Medical Center , PO Box 2040, 3000 CA, Rotterdam , The Netherlands
1 EMGO Institute for Health and Care Research and the Department of Epidemiology and Biostatistics, VU University Medical Center , Van der Boechorststraat 7, 1081 BT, Amsterdam , The Netherlands
2 Centre for Physical Activity and Nutrition Research, Deakin University , 221 Burwood Highway, Burwood, VIC 3125 Australia
3 The Author 2010. Published by Oxford University Press. All rights reserved. Downloaded from https://academic.oup.com/her/article-abstract/25/3/489/656624 by guest on 01
This longitudinal study aimed to identify individual and environmental predictors of adolescents' sports participation and to examine whether availability of sports facilities moderated the intention-behaviour relation. Data were obtained from the ENvironmental Determinants of Obesity in Rotterdam SchoolchildrEn study (2005/2006 to 2007/2008). A total of 247 adolescents (48% boys, mean age at follow-up 15 years) completed the surveys at baseline and follow-up. At baseline, adolescents completed a survey that assessed engagement in sports participation, attitude, subjective norm, perceived behavioural control and intention towards sports participation. Availability of sports facilities (availability) was assessed using a geographic information system. At follow-up, sports participation was again examined. Multiple logistic regression analyses were conducted to test associations between availability of sports facilities, theory of planned behaviour variables and the interaction of intention by availability of sports facilities, with sports participation at follow-up. Simple slopes analysis was conducted to decompose the interaction effect. A significant availability 3 intention interaction effect [odds ratio: 1.10; 95% confidence interval: 1.00-1.20] was found. Simple slopes analysis showed that intention was more strongly associated with sports participation when sports facilities were more readily available. The results of this study indicate that the intention-sports participation association appears to be stronger when more facilities are available.
Promoting physical activity (PA) is an important
public health priority [
]. Besides daily activities
of moderate intensity, more intensive sport
activities to increase physical fitness are also
recommended, especially for children and adolescents [
Moderate and higher intensity activities are
beneficial for health, quality of life and social integration
during adolescence, as well as later in life [
2, 3, 5?
]. Furthermore, continuous PA throughout youth
increases the probability of becoming an active
]. However, even though many adolescents
in Western countries engage in sports activities
when they are younger [
], engagement in sports
declines rapidly during adolescence [
]. Thus, it
is important to promote sports participation in
adolescence. To do this efficiently, interventions
should be theory and evidence based  and
intervene on important modifiable behavioural
]. The present study aims to identify
individual and environmental determinants of
sports participation and their potential interplay.
According to socio-ecological models [
and extended motivational models [
is not only determined by predictors at the
individual level (i.e. cognitions) but also by environmental
factors, such as availability of sports facilities.
These models also assume an interplay between
individual cognitions and environmental factors
through mediation [
] or moderation [
recently, most studies, exploring determinants of
PA and sports participation, focused on the
individual level correlates, such as derived from the theory
of planned behaviour (TPB) [
]. According to
the TPB, behavioural intention (i.e. the decision to
engage in a specific behaviour) is the most proximal
determinant of behaviour . Intention in turn is
determined by attitudes, subjective norm and
perceived behavioural control (PBC). Attitudes refer to
a person?s evaluation of the advantages and
disadvantages of engagement in a specific behaviour.
Subjective norm is related to the perception of what
important others think you should do. Perceived
behavioural control refers to the perceived ease or
difficulty of performing a specific behaviour. The
few studies available that used the TPB for
explaining sports participation did not find consistent
results with regard to the predictability of intention
on sports behaviour. Other studies have focussed on
built environmental factors, such as the availability
and accessibility of PA opportunities, as potential
determinants of sports participation among
]. There are, however, few studies
that take both individual and environmental
determinants of sports participation and their
interrelationship into account, and the studies that have
done so mainly have relied on a cross-sectional
design, weakening the interpretation of the
In the present study, the potential moderating
effect of environmental-level predictors on the
intention?behaviour relation suggested by Fishbein
] in the extended TPB model is examined.
According to this model, the environment, such as
the availability of sports facilities, can act as a
facilitator for behaviour. Hence, when sports facilities
are available, people are more likely to act on their
positive intentions, suggesting a stronger intention?
behaviour association in circumstances of high
availability. Insight into these mechanisms may
help to shape PA promotion interventions for
adolescents and may contribute to the explanation of
the intention?behaviour gap, as has been observed
for PA and other behaviours [
Few studies have examined the role of
environmental factors on the intention?behaviour
association. One study found that the proximity to
recreational facilities moderates the intention?
walking behaviour association in adults [
another found no evidence of moderation of active
transportation among students [
]. Both studies
used a self-report measure of the built environment,
which was seen as an important limitation [
The aim of the present longitudinal study was to
identify individual and environmental predictors of
adolescent sports participation and to examine if the
objective availability of sports facilities moderates
the intention?behaviour relationship. We
hypothesized that (i) intentions are significantly associated
with sports participation at follow-up, (ii)
objectively measured availability of sports facilities is
associated with sports participation at follow-up
and (iii) objectively measured availability of sports
facilities moderates the association between
intention at baseline and sports participation at
followup, with more facilities contributing to a stronger
This study draws on longitudinal data from the
study on ENvironmental Determinants of Obesity
in Rotterdam SchoolchildrEn (ENDORSE). The
ENDORSE study was conducted in Rotterdam in
2005?2006 (baseline) and 2007?2008 (follow-up)
among adolescents in the first and third year
of secondary education. This is an age period
in which considerable declines in sports
participation can be expected [
]. Rotterdam is the
second largest city of The Netherlands, with
approximately 600 000 inhabitants, of which 46%
are of non-Dutch origin . The medical ethics
committee of the Erasmus University Medical
Center in Rotterdam issued a ?declaration of no
objection? for the study. A detailed description of
the study protocol is published elsewhere [
Sampling and procedure
At baseline, 56 schools were approached to take
part in the study and 24 schools were willing to
participate. A random selection of 17 of these
schools participated in the study. These schools
were selected after stratification according to the
area of the city in which they were located (north,
south, east or city centre) to ensure a range of
physical and cultural environments. Approximately five
classes within each school were selected for the
study. Thirteen schools had classes with
adolescents in their first year of secondary education at
baseline, and these schools were included in the
present study. During one school hour, the
adolescents completed a printed questionnaire on dietary
and PA behaviours and potential determinants of
these behaviours in the presence of a research
assistant and a teacher.
In this paper, we analysed the data on sports
behaviour from ENDORSE and additional
objective measures of availability of sports facilities in
the local neighbourhood. Only adolescents who
lived in neighbourhoods within the city of Rotterdam
that were not adjacent to other municipalities were
eligible for analyses because objective
environmental data were only available for Rotterdam. A total
of 488 adolescents met this inclusion criterion at
An adapted version of the Activity QUestionnaire
for Adolescents and Adults (AQUAA) [
used to assess PA levels at baseline and
followup. The AQUAA showed a fair to moderate test?
retest reproducibility, with intra-class correlations
ranging from 0.44 to 0.59. Items related to
frequency of sports participation were used in this
Adolescents were asked to name up to three
sports they had participated in during the previous
week and indicate on how many days of the week
(0?7 days) they had participated in each sports
activity. An overall measure of frequency of sports
participation per week was created by summing
the frequencies of the reported sports activities at
baseline and at follow-up, respectively. These
variables were collapsed into two categories [yes (1),
participated in some sports and no (0), did not
participate in any sports] due to the skewed distribution.
All TPB variables were measured at baseline using
five-point response scales. Attitude was assessed by
two items using semantic differential response
scales ?I think that sports and leisure time physical
activity are .? [very good (5) to very bad (1) and
very pleasant (5) to very unpleasant (1)].
Cronbach?s alpha of the attitude items was 0.80 and
a mean attitude score was calculated. PBC was
assessed by two items, assessing perceived
capability and control (Cronbach?s alpha = 0.27).
However, as the Cronbach?s alpha was low, it was
decided to use these items as separate scales in
the analyses. Capability was assessed by the item
?How easy or difficult would it be for you to engage
in sports or leisure time physical activity if you
want to?? [very easy (5) to very difficult (1)].
Control was assessed by the item ?To what extent do
you decide for yourself to engage in sports or
leisure time physical activity?? [I decide it all by
myself (5) to I do not decide this by myself at all (1)].
One item was used to assess parental subjective
norm: ?If I engage in sports or physical activity,
my parents think that this is .?? [very good (5)
to very bad (1)]. Intention was also assessed by
one item: ?Do you plan to start/remain engaging
in sports and physical activity in the next half year??
[yes certainly (5) to certainly not (1)].
Objective physical environment
Geographical information system (GIS) data on the
availability of sports facilities at baseline were
retrieved from a database managed by the municipality
of Rotterdam. This database contains geographical
co-ordinates of sports facilities (including sports
halls, skate parks, fitness centers, sporting grounds
and swimming pools). Addresses of adolescents?
homes were geocoded by using the centroid of the
six-digit zip codes of their home address. ArcGIS 9.3
was used to count the number of sports facilities
within a crow-fly buffer of 1600 m (i.e.
approximately 1 mile) from the adolescents? home. This
radius was based on a study by Colabianchi et al.
] in which an average acceptable travel time of
15 min was found. Given that cycling is a common
mode of transport in The Netherlands, 1600 m can
be easily reached within 15 min.
The baseline ENDORSE questionnaire provided
information on gender and country of birth of the
adolescents, their mothers and fathers and from
these variables an ethnic background variable
(Western or non-Western) was constructed
according to the standards of Statistics Netherlands [
In The Netherlands, secondary education is
provided at different levels, ranging from lower
vocational to senior general secondary education
schools preparing for universities. School level
was categorized into higher general secondary
education (i.e. preparatory education for university)
and vocational education.
Descriptive statistics were used to describe the
study population. Clustering of behaviour in
neighbourhoods was tested in MLwiN 2.02 by
calculating the intra-cluster coefficient (ICC) of the
nill-model of sports participation (i.e. only the
intercept was in the model) and by testing
significance of variation. No significant clustering in
neighbourhoods was observed (ICC: 0.06,
neighbourhood level variance 0.30, 95% confidence
interval: 0.36 to 0.81). Therefore, it was decided
to conduct all analyses in SPSS 15.0 without
adjustments for clustering at the neighbourhood level.
Bivariate Spearman correlations were calculated
to analyse univariate associations between the
cognitive, environmental and behavioural
variables. Subsequently, multiple logistic regression
analyses were conducted to test associations between
TPB variables and availability of sports facilities at
baseline with sports participation at follow-up. All
analyses were adjusted for gender, age, school level,
ethnicity and sports participation at baseline.
Variables were entered stepwise: in the first step
demographics and sports participation at baseline; in the
second step availability of sports facilities; in the third
step attitude, subjective norm and PBC; in the fourth
step intention and in the last step the intention 3
availability of sports facilities interaction term. If
the interaction term proved to be significant (P <
0.10), simple slope analyses were conducted to
visualize the moderation effect by using an SPSS
script developed by Hayes and Matthes [
to severe skewness and therewith problematic
interpretation of the simple slopes analyses, intention was
dichotomized based on median split. The
dichotomized intention variable was used in all analyses.
For all associations, a result was considered
significant if the P-value was lower than 0.05 for
a two-sided test.
Participants and dropout
Adolescents eligible for the analyses at baseline
(N = 488) were significantly more likely to be girls
and of non-Western origin than those not eligible at
baseline for analyses (N = 211). Follow-up data
were available for 288 of the adolescents included
for analysis (59%). The other 41% could not be
traced because they had left school, declined to
participate or were absent during the week that
follow-up measurements took place. Adolescents
with follow-up data were significantly more likely
to participate in sports at baseline (72 versus 62%;
P < 0.01) and were on average 0.14 years younger
than those without follow-up data. Of the
adolescents with follow-up data, 41 (14%) did not have
complete data on the variables of interest. The
sample available for analyses thus consisted of
The average age of the final sample at baseline was
13.2 (SD: 0.6) years and at follow-up 15.2 (SD: 0.6)
years; 57.6% of the adolescent sample had a
nonWestern ethnicity and 47.9% were male. A majority
of adolescents reported to participate in sports at
baseline (74.1%). At follow-up, however, sports
participation had declined to 47.9%. On average,
adolescents in the final sample had 14.94 (SD:
8.13) sports facilities available within a radius of
1600 m (Table I). At baseline, adolescents reported
on average a positive attitude (mean: 4.4; SD: 0.6;
range: 2.5?5), subjective norm (mean: 4.6; SD: 0.6;
range: 3?5), control dimension of PBC (mean: 4.3;
SD: 0.8; range: 1?5), the capability dimension of
PBC (mean: 4.5; SD: 0.7; range: 2?5) and intention
(68% in high category) towards sports and PA
Bivariate correlations showed positive associations
between availability of sports facilities and attitudes
towards sports and the control dimension of PBC,
but not with behaviour at follow-up. Positive
associations were also found between attitude,
subjective norm, the capability and control dimension of
PBC and intention to participate in sports (Table I).
Intention at baseline was positively correlated with
sports participation at follow-up. Most effect sizes
were small or medium [
Multivariate analyses of intention and availability of sports facilities with sports participation
The results of the multivariate logistic regression
analyses are shown in Table II. The number of
sports facilities available at baseline was not
associated with participation in sports at follow-up, after
adjustment for demographics and sports
participation at baseline. Of the TPB variables entered in
Step 3, attitude and subjective norm were
significantly associated with sports participation. Attitude
remained significant in the subsequent and final
model. Subjective norm was also significant in the
final model. Intention at baseline, entered in Step 4,
was not significantly associated with sports
participation at follow-up. The availability 3 intention
interaction term was significantly associated with
sports participation at follow-up, indicating
moderation of availability on the intention?sports
Moderation of the availability of sports facilities on the intention?behaviour relation
Simple slope analyses were conducted to interpret
the availability 3 intention interaction effect
(Fig. 1). In this figure, the predicted probability of
participating in sports is plotted for two levels of
intention (low and high) for three levels of
availability (low availability, 1 SD below mean; mean
Small effect size: r > 0.10; medium effect size: 0.30 < r < 0.50; large effect size r = >0.50. 1, Availability of sports facilities; 2, Attitude;
3, PBC?control; 4, PBC?capability; 5, Subjective norm; 6, Intention.
**P < 0.01.
Significant values are represented in bold. CI, confidence interval. OR, odds ratio.
aReference is high education.
bReference is male.
cReference is western background.
dSports participation at baseline or not (1/0).
eDichotomized measure (0 = low, 1 = high).
Step 1 OR
availability and high availability, 1 SD above
mean). Figure 1 shows that the intention?sports
participation relationship is stronger with
increasing availability of sports facilities.
This study aimed to identify individual and
environmental predictors of adolescent sports participation
and to examine whether availability of sports
facilities moderated the intention?behaviour relation. In
summary, we found that attitude and subjective
norm were associated with sports participation at
follow-up. Intention was associated with sports
participation in the univariate analyses, but not in the
multivariate models. Availability of sports facilities
was not associated with sports participation.
However, the availability of sports facilities significantly
moderated the intention?sports participation
association, with the intention?behaviour relationship
being stronger when there were more facilities
available. The study also confirmed results of earlier
], showing large declines in sports
participation during adolescence.
This study is among the first to examine aspects
of the physical environment as a moderator of the
intention?behaviour relationship for PA among
adolescents. Further strengths of the study include
its longitudinal design and the objective assessment
of sports facilities availability. In line with our
hypothesis, we found that the availability of sports
facilities moderates the intention?sports participation
relation in such a way that a higher availability of
sports facilities contributes to a stronger intention?
behaviour relationship. Similar results were found
by Rhodes et al. [
] for neighbourhood recreation
facilities and walking among adults. Our findings
support the proposition that the environment is a
relevant prerequisite for being physically active but is
not sufficient to promote PA levels [
sufficient facilities are available, intention to be more
active appears to be of additional importance.
Availability of sports facilities may facilitate sports
participation for those with a positive intention, which
is in line with the assumptions in Fishbein?s [
model in which it is postulated that the environment
may provide the opportunity to act on positive
intentions. Thus, lack of appropriate availability of
sports facilities may be one of the reasons for the
intention?behaviour gap. The inconsistent findings
in the literature [
] on the relationship between
intentions and sports participations can potentially
be explained by the present findings.
In contrast to what we had hypothesized, we did
not observe a significant direct association of sports
facilities at baseline on sports participation at
follow-up. Even though such relationships are
assumed in ecological models such as the EnRG
], so far empirical evidence does
not show consistent results. Some studies have
shown associations between objectively measured
availability and PA behaviour among adolescents
], while others have not [
]. Most of
these studies had a cross-sectional design. Reasons
for inconsistent findings may be methodological
issues in the measurement of environmental
influences, such as the buffer sizes used to objectively
capture the environment.
Additionally, it is noteworthy that we did find
direct associations between attitude, subjective
norm and sports participation that were not
specifically hypothesized. The direct attitude?behaviour
relationship has also been shown for other
healthrelated behaviours [
], and could potentially be
explained by the MODE (Motivation and
Opportunity as DEterminants) model [
], which suggests
that when attitudes are strong (i.e. easily accessible
from memory), people may automatically act on
them. The direct effect of the subjective norm
may be explained by its measurement as parental
norm. Whereas norms are normally operationalized
as the expectations of others, the influence of
parents may go beyond that of a motivational drive
and may reflect actual support. Hence, within
adolescence, the role of parents is likely to be
important, both indirectly as a motivator and directly as
a facilitator of various health-related behaviours.
There are limitations that have to be taken into
account in interpreting the results. Firstly, the time
span between baseline and follow-up
measurements was 2 years, which may be too long to find
a strong association between determinants and
behaviour, especially since the intention item was
framed as intention to do PA or sports within 6
months. Secondly, the TPB constructs are measured
with a limited number of items which might
question the validity of the operationalization. However,
the inter-item correlations and relationship of TPB
variables with intention (data not shown) and
behaviour are comparable to other studies [
Thirdly, adolescents who did not participate in
sports at baseline were less likely to be included
in the study since they were more likely to have
no follow-up data. Furthermore, this study was
conducted among a sample of urban Dutch adolescents.
Care should be taken in generalizing these results to
other populations. A final limitation is that PA was
self-reported. Although the instrument was reliable,
reporting of PA behaviour may not have been
In conclusion, this study indicates that
objectively measured availability of sports facilities
moderates the longitudinal association between
intention and sports participation among
adolescents. If confirmed in further research, the
implication may be that motivating adolescents to engage
in sports is indeed more useful when sufficient
opportunities are present.
Netherlands Organization for Health Research and
Development (ZonMW; 7110.0001 to R.G.P, P.E.
and A.O., 12200003 to F.J.L.); The World Cancer
Research Fund (2007/47 to S.V., N.T. and J.B.);
Public Health Research Fellowships from the
Victorian Health Promotion Foundation to A.T. and
Conflict of interest statement
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