Journal of Adolescence 35 (2012) 1399–1402

Contents lists available at SciVerse ScienceDirect

Journal of Adolescence

journal homepage: www.elsevier .com/locate/ jado

Brief report: Relationships between physical activity and depressivesymptoms in adolescent girls

Lennart Raudsepp*, Inga NeissaarInstitute of Sport Pedagogy and Coaching Science, University of Tartu, Jakobi 5, Tartu 51014, Estonia

Keywords:Physical activityDepressionLongitudinal associations

* Corresponding author. Tel.: þ372 7375802.E-mail addresses: lennart.raudsepp@ut.ee (L. Rau

0140-1971/$ – see front matter � 2012 The Foundadoi:10.1016/j.adolescence.2012.04.003

a b s t r a c t

This study examined the relationships between changes in physical activity and depressivesymptoms in adolescent girls. Participants were 277 urban adolescent girls. Physicalactivity was measured using the 3-Day Physical Activity Recall and depressive symptomswere assessed using questionnaire. Data were collected on three occasions over a 3-yearperiod. The results of latent growth modelling indicated that initial level and change inphysical activity was inversely associated with initial status and change in depressivesymptoms The associations were independent of body mass index. Our results encouragethe design of interventions that reduce depressive symptoms and increase physical activityof early adolescent girls.� 2012 The Foundation for Professionals in Services for Adolescents. Published by Elsevier

Ltd. All rights reserved.

Depression occurs in up to 10 percent of adolescents (Rushton, Forcier, & Schectman, 2002) and studies suggest thatdepressed youth may be at particularly high risk of multiple health risk behaviours, such as smoking, obesity, and substanceuse (Katon et al., 2010). The prevalence of depressive symptoms increases during early to mid-adolescence, with the mostdramatic increases evident for girls (Joiner & Tickle, 1998). Depressive disorders among youth commonly persist, recur, andcontinue into adulthood and predict more severe depressive illness in the adult years (Weismann et al., 1999).

A relationship has been shown between regular physical activity and low levels of indicators of mental illness, such asdepression and depressed mood, among adolescents (Birkeland, Torsheim, &Wold, 2009; Motl, Birnbaum, Kubik, & Dishman,2004). However, few studies have tested the longitudinal relationship between physical activity and depressed mood duringearly adolescence and the accumulated evidence is conflicting (Sund, Larsson, & Wichstrom, 2010; Ussher, Owen, Cook, &Whincup, 2007). A review by Larun and colleagues concluded that the relationships between physical activity and adoles-cent depression are generally unknown because the evidence base is extremely scarce (Larun, Nordheim, Ekeland, Hagen, &Heian, 2009). Most research has used cross-sectional designs and did not adjust for other risk factors such as adiposity thatmight confound the association between physical activity and depressive symptoms (Ussher et al., 2007). In the current study,the effects of bodymass index (BMI) on the longitudinal relationships among physical activity and depressive symptomswerecontrolled.

Based on the difficulty understanding the causal nature of the relationships between physical activity and depressivesymptoms, we examined the relationships between changes in physical activity and depressive symptoms in adolescent girlsacross a 3-year period. A better understanding of these relationships and their relative strength may better inform those whowish to help individuals maintain physical activity habits, reduce depressive symptoms, and thereby minimize healthproblems.

dsepp), inga.neissaar@ut.ee (I. Neissaar).

tion for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

L. Raudsepp, I. Neissaar / Journal of Adolescence 35 (2012) 1399–14021400

Method

Participants and procedures

The participants in this study were 277 adolescent girls ranging in age at the beginning of study from 12 to 13 years (Mage ¼ 12.4 years, SD ¼ 0.4). The study drew on data collected from approximately half of the Grade 7 students in the city ofTartu. Prior to the start of the study, permission to conduct the study was obtained from the University Ethics Committee aswell as from the schools. Additionally, participants and their parents were given consent letters, which explained the aimsand procedures of the study.

Datawere collected on three occasions over a 3-year period. The three occasions were Fall 2006 (baseline data of 366 girls),Spring 2008 (interim data of 308 girls), and Fall 2009 (follow-up data of 277 girls). Questionnaires were completed duringhealth education classes. Survey procedures were designed to protect the privacy of the participants.

Measures

Physical activityGirls’ physical activity was assessed using the 3-Day Physical Activity Recall (3DPAR) (Motl, Dishman, Dowda, & Pate,

2004). The 3DPAR has been shown to be a valid measure of daily physical activity as compared to accelerometry (Motl,Birnbaum et al., 2004; Motl, Dishman et al., 2004). The 3DPAR asks participants to recall the activities that they partici-pated in during themajority of each 30-min time blocks between 6 a.m. andmidnight on the three days previous to the day ofdata collection. The 3DPAR was always completed on aWednesday. Girls selected the activity that they participated in for themajority of each half hour block from a list on 65 common physical activities and sedentary behaviours. Therefore, a block canbe considered to be equivalent to between 15 and 30 min of activity as it is possible that the girls did not participate in thephysical activity for the full half hour (Motl, Birnbaum, et al., 2004; Motl, Dishman, et al., 2004). Total physical activity wasdefined as a per day average number of blocks for which any physical activity was reported.

Depressive symptomsDepressive symptoms were measured using 20 items from the CES-D, which has established predictive validity for the

screening of adolescent depression (Roberts, Lewinsohn, & Seeley, 1991). The 20 items were rated on the basis of frequency ofoccurrence during the previous week.

Body mass index (BMI)Body height was measured using Martin’s metal anthropometer to the nearest 0.1 cm; body weight was measured with

medical scales to the nearest 0.1 kg and BMI (weight/height squared) was computed.

Data analysisWe applied latent growth modelling (LGM) to examine the consequence of a change in physical activity on a change in

depressive symptoms. In addition, a possible confounding influence of BMI on physical activity-depressive symptoms rela-tionship was also tested. The LGM analyses were conducted using AMOS 6.0 software with full-information maximumlikelihood estimation. Three indices of model fit were used. The chi-square statistic (c2) assessed absolute fit of the model tothe data. Values for the root mean square error of approximation (RMSEA) of 0.05 or less are indicative of goodmodel fit. Also,we calculated the comparative fir index (CFI) for which a value of 0.95 or greater indicates a good model fit (Hu & Bentler,1999).

Results

Table 1 provides the correlations, means, and standard deviations for the variables in the study. Intercorrelations betweenphysical activity and depressive symptoms ranged from �0.19 to �0.29.

Table 1Descriptive statistics and zero-order correlations among the study variables (n ¼ 277).

Variables Mean SD Correlation matrix

1 2 3 4 5 6 7

1. Physical activity T1 (blocks$day�1) 3.8 0.7 1.002. Physical activity T2 3.4 0.8 0.55 1.003. Physical activity T3 3.1 0.6 0.46 0.49 1.004. Depressive symptoms T1 19.2 3.3 �0.29 �0.25 �0.24 1.005. Depressive symptoms T2 19.7 3.5 �0.24 �0.20 �0.26 0.47 1.006. Depressive symptoms T3 20.9 3.7 �0.19 �0.27 �0.25 0.51 0.44 1.007. BMI (kg/m2) 20.7 2.6 �0.41 �0.33 �0.28 �0.22 �0.15 �0.17 1.00

All correlations were statistically significant (p < 0.05).

PA Initial

Status ( 1)

PA Optimal

Slope ( 2)

DS Initial Status ( 3)

DS Optimal Slope ( 4)

3,1 = -0.25

1

4,2 = -0.33

Y4

Y5

Y6

Y1

Y2

Y3

2

3

4

Fig. 1. A model that included direct effects of initial status and change for physical activity (PA) on initial status and changes for depressive symptoms (DS). BMIwas included in the model, but the effect BMI and associated path coefficients are not provided in the figure for clarity. Y1–Y6 present indicators of physicalactivity and depressive symptoms measured at baseline, interim, and follow-up.

L. Raudsepp, I. Neissaar / Journal of Adolescence 35 (2012) 1399–1402 1401

Fig. 1 showed path coefficients between physical activity and depressive symptoms.This model provided a good fit to the data (c2 ¼ 219.4, p < 0.05, CFI ¼ 0.957, RMSEA ¼ 0.052). In addition, when physical

activity-to-depressive symptoms and depressive symptoms-to-physical activity alternative models were compared, therewere no statistically significant differences in model characteristics. In sum, there were statistically significant and negativerelationships between initial status factors (b ¼ �0.25) and change factors (b ¼ �0.33) for physical activity and depressivesymptoms. Themodel accounted for 21% of the variance in initial status of physical activity and 25% of the variance in physicalactivity change. Results were independent of BMI.

Discussion

The current study used latent growth modelling to examine the relationships between physical activity and depressivesymptoms in adolescent girls. After controlling for the effect of BMI, physical activity demonstrated an inverse associationwith depressive symptoms in girls across early adolescence. Although we have adopted the perspective that change inphysical activity preceded change in depressive symptoms, it is also possible that naturally occurring increases in depressivesymptoms contribute to the decline in physical activity in adolescent girls.

Considering the negative relation between physical activity participation and depressive symptoms, this finding is in linewith previous longitudinal studies (Joiner & Tickle, 1998; Motl, Birnbaum, et al., 2004; Sagatun, Sogaard, Bjertness, Selmer, &Heyerdahl, 2007). According to the “protection hypothesis,” physical activity protects against depressed mood and severalbiological and psychological mechanisms have been proposed to suggest how this protection effect occurs (Birkeland et al.,2009). For example, psychological hypotheses propose that physical activity provides experiences of mastery and control,influences self-esteem, is a distractor from everyday stressors and negative thoughts, and improves the retrieval of positivethoughts (Salmon, 2001). However, it is also possible that depressed mood, at least to some degree, disables an individual’sability to be physically active (Goodwin, 2003). Additionally, the findings of our analysis might be explained by a common“third“ factor related to both physical activity and the emergence of depressive symptoms.

This study is limited in that physical activity was self-reported and the sample of adolescent girls was relatively small.Additionally, we are unable to specify whether changes in physical activity are cause or consequence of changes in depressivesymptoms. This only can be evaluated by a randomized controlled trial. The strengths of the present study are the longitudinalnature of the data and design and the use of LGM. There are many advantages of LGM, including its flexibility and value formodelling developmental processes, and its ability to identify important predictors and outcomes of change (Park & Schutz,2005).

References

Birkeland, M. S., Torsheim, T., & Wold, B. (2009). A longitudinal study of the relationship between leisure-time physical activity and depressed mood amongadolescents. Psychology of Sport and Exercise, 10, 25–34.

Goodwin, R. D. (2003). Association between physical activity and mental disorders among adults in the United States. Preventive Medicine, 36, 698–703.Hu, L., & Bentler, P. M. (1999). Cutoff criteria for the fit indexes in covariance structure analysis: conventional criteria versus new alternatives. Structural

Equation Modeling, 6, 1–55.Joiner, T. E., & Tickle, J. J. (1998). Exercise and depressive and anxious symptoms: what is the nature of their interrelations? Journal of Occupational

Rehabilitation, 8, 191–198.

L. Raudsepp, I. Neissaar / Journal of Adolescence 35 (2012) 1399–14021402

Katon, W., Richardson, L., Russo, J., McCarty, C. A., Rockhill, C., McCauley, E., et al. (2010). Depressive symptoms in adolescence: the association with multiplehealth risk behaviors. General Hospital Psychiatry, 32, 233–239.

Larun, L., Nordheim, L. V., Ekeland, E., Hagen, K. B., & Heian, F. (2009). Exercise in prevention and treatment of anxiety and depression among children andyoung people. Cochrane Database of Systematic Reviews, Cochrane AN: CD004691.

Motl, R. W., Birnbaum, A. S., Kubik, M. Y., & Dishman, R. K. (2004). Naturally occurring changes in physical activity are inversely related to depressivesymptoms during early adolescence. Psychosomatic Medicine, 66, 336–342.

Motl, R. W., Dishman, R. K., Dowda, M., & Pate, R. R. (2004). Factorial validity and invariance of a self-report measure of physical activity among adolescentgirls. Research Quarterly for Exercise and Sport, 75, 259–271.

Park, I., & Schutz, R. W. (2005). An introduction to latent growth models: analysis of repeated measures physical performance data. Research Quarterly forExercise and Sport, 76, 176–192.

Roberts, R. E., Lewinsohn, P. M., & Seeley, J. R. (1991). Screening for adolescent depression: a comparison of DES-D and BDI. Journal of the American Academyof Child and Adolescent Psychiatry, 20, 58–66.

Rushton, J. L., Forcier, M., & Schectman, R. M. (2002). Epidemiology of depressive symptoms in the National Longitudinal Study of Adolescent Health. Journalof the American Academy of Child and Adolescent Psychiatry, 41, 199–205.

Sagatun, A., Sogaard, A. J., Bjertness, E., Selmer, R., & Heyerdahl, S. (2007). The association between weekly hours of physical activity and mental health:a three-year follow-up study in 15–16-year-old students in the city Oslo, Norway. BMC Public Health, 7, 115.

Salmon, P. (2001). Effects of physical exercise on anxiety, depression, and sensitivity to stress: a unifying theory. Clinical Psychology Review, 21, 33–61.Sund, A. M., Larsson, B., & Wichstrom, L. (2010). Role of physical and sedentary activities in the development of depressive symptoms in early adolescence.

Social Psychiatry and Psychiatric Epidemiology, 19. doi:10.1007/s00127-01-0208-0.Ussher, M. H., Owen, C. G., Cook, D. G., & Whincup, P. H. (2007). The relationship between physical activity, sedentary behaviour and psychological wellbeing

among adolescents. Social Psychiatry and Psychiatric Epidemiology, 42, 851–856.Weismann, M. M., Wolk, S., Goldstein, R. B., Moreau, B., Adams, P., Greenwald, S., et al. (1999). Depressed adolescents grown up. Journal of American Medical

Association, 281, 1701–1713.