Walking for depression or depressive symptoms: A systematic review and meta-analysis
Highlights
► A systematic review and meta-analysis of walking as a treatment for depression. ► Eight randomised controlled trials with 341 participants were included. ► The pooled standardised mean difference (effect size) was ∼0.86 [∼1.12, ∼0.61]. ► Walking has a similar effect size for treating depression as other exercise types. ► Research in implementing findings in primary care settings is warranted.
Introduction
Depression is an illness or mood disorder with a variety of symptoms, the most defining being an inexplicable, enduring feeling of sadness (loss of positive affect). It is categorised as mild, moderate or severe depending upon the number and severity of the symptoms (WHO, 2010). It is a common mental health problem, estimated in 2000 to be the fourth leading cause of disease burden worldwide (Ustun et al., 2004, WHO, 2003). It causes a level of morbidity comparable to or worse than other common chronic diseases such as asthma and diabetes (Moussavi et al., 2007). In the UK over 75% of patients with depression are treated solely within primary care (NICE, 2010) where prevalence is estimated at 7% (Ostler et al., 2001).
Depression is commonly treated with antidepressant medications, psychological therapies or a combination of both. The efficacy of antidepressants for mild depression has been questioned (Moncrieff & Kirsch, 2005) and they are not recommended to be used routinely by people with persistent sub-threshold depressive symptoms or mild depression in the first instance (NICE, 2010). There is also a range of side effects (Demyttenaere, 2003), many people do not like taking medicines (Givens et al., 2006, Kessing et al., 2005, Maxwell, 2005, Townsend et al., 2003) and early drop-out rates in clinical trials vary from 12% to 40% (Cipriani et al., 2009, Kirsch et al., 2008). Psychological therapies are resource intensive, and may require cognitive capabilities a person with depression cannot attain. Consequently, for many years there has been interest in physical activity (and other alternative therapies) as a stand-alone or adjunctive treatment for depression (Scottish Intercollegiate Guidelines Network, 2010). Several systematic reviews (Lawlor and Hopker, 2001, Mead et al., 2008, Mead et al., 2009, Sjosten and Kivela, 2006) and a review of reviews (Daley, 2008) have concluded that exercise appeared to improve symptoms of depression, but that the methodological quality of available trials was often too poor to reach a robust conclusion. A further meta-analysis by Stathopoulou (Stathopoulou, Powers, Berry, Smits, & Otto, 2006, p. 188) concluded that “exercise can be a powerful intervention for clinical depression”, and another systematic review of the effect of exercise in clinically depressed adults by Krogh et al. found that there was a short-term positive effect of exercise on depression but no positive long-term effect (Krogh, Nordentoft, Sterne, & Lawlor, 2011). For patients with persistent sub-threshold or mild to moderate depression, current UK NICE guidelines (NICE, 2010) recommend structured physical activity programmes, individual guided self-help based on cognitive behaviour therapy (CBT) principles and/or computerised CBT as treatment choices. It is recommended that the physical activity programmes are group based and led by a trained practitioner thrice weekly for 45 min to 1 h for a period of 10–14 weeks.
Walking is a form of physical activity that has the potential to alleviate depression. When taken outdoors, the addition of being able to observe or experience an attractive natural environment has been shown to have a restorative effect, decreasing levels of stress, (Hartig et al., 1991, Kaplan and Kaplan, 1989, Ulrich, 1983) which could contribute to reducing symptoms of depression. Walking has the advantages of being easily undertaken by most people, incurring little or no financial cost, having minimal risk of adverse effects and being relatively easy to incorporate into daily living. Consequently, walking is promoted in many developed countries throughout the world (Steps Project, 2011, Centers for Disease Control and Prevention, 2011, Health Canada, 2011, International Longevity Center-USA, 2011, Natural England, 2011, NHS Choices Information, 2011, Paths for All, 2011, Welsh Assembly Government, 2011) to counteract increasingly sedentary lifestyles and the health consequences of physical inactivity. While existing systematic literature reviews with meta-analyses (Krogh et al., 2011, Lawlor and Hopker, 2001, Mead et al., 2009) have found positive, but not conclusive evidence, to support exercise as an intervention for depression, to our knowledge no review to date has evaluated the effectiveness of specific types of physical activity.
A variety of mechanisms to explain why physical activity might reduce depressive symptoms has been suggested (Craft & Perna, 2004). These include biochemical (including endorphin and monoamine hypotheses), physiological (thermogenic, cardiovascular fitness, and sleep improvement hypotheses) and psychological and psychosocial hypotheses such as distraction, self-efficacy and enhancement of self-esteem (Sonstroem & Morgan, 1989) or increasing positive affect (Clark and Watson, 1991, White et al., 2009). Whichever mechanism or combination of mechanisms are responsible for physical activity reducing depressive symptoms, there is uncertainty regarding the optimum dose (duration and frequency of sessions, length of programme) and intensity and which specific type(s) of physical activity benefit depression (Mead et al., 2008). It is not known whether walking is a form of physical activity that is sufficiently vigorous to stimulate sufficient biochemical or physiological changes to be an effective treatment for depression and whether walking interventions contribute to or diminish the overall effect sizes reported.
If the available evidence were able to demonstrate that walking is an effective physical activity for the treatment of depression, this knowledge could inform current recommendations and give health professionals greater confidence in the benefits of walking when advising patients who are depressed. We therefore carried out a systematic review of the existing literature to examine the effectiveness of walking as an intervention for alleviating depression in adults, and performed a meta-analysis on relevant data. Further, we considered walking outdoors, walking indoors and walking in a group.
Section snippets
Literature search
The following key words were translated into the appropriate search syntax for the databases listed below:
- (i)
depression, depressive disorder, dysthymia, affective disorder, mood
- (ii)
walk, walking, ambulatory, physical activity
- (iii)
randomised controlled trial
Searches were conducted with no language restrictions in electronic databases from the date the database was first published until August 2009, and updated in January 2012. The databases searched were: MEDLINE, AMED, EMBASE, PsycInfo, CINAHL, Physical
Results
A total of 14,672 titles was retrieved, the abstracts of 364 were considered and the full texts of 103 trials were obtained (Fig. 1). From these, seven separate trials fully met the inclusion criteria (Armstrong and Edwards, 2003, Armstrong and Edwards, 2004, Bonnet, 2005, Knubben et al., 2007, McNeil et al., 1991, Mota-Pereira et al., 2011, Nguyen, 2008). We decided to include one further trial (Gusi, Reyes, Gonzalez-Guerrero, Herrera, & Garcia, 2008), which recruited participants with a high
Discussion
Our meta-analysis of eight randomised, controlled trials found that walking was an effective intervention for depression having an effect size of −0.86 [−1.12, −0.61]. This is comparable to the results of several recent systematic reviews and meta-analyses of physical activity (not restricted to walking) as a treatment for depression. The most recent of these reviews of which we are aware (Krogh et al., 2011) reported a lower effect size, with a pooled standardised mean difference of −0.40 (95%
Conclusions
Walking has a statistically significant, large effect on the symptoms of depression in some populations but the current evidence base from randomised, controlled trials is limited.
Given that walking is potentially a widely accessible, safe and inexpensive treatment and in view of the high prevalence of depression in primary care patients, we recommend that future research should focus on evaluating walking interventions delivered in primary care settings. Investigations are needed to establish
Acknowledgements
We thank Marshall Dozier (Senior Liaison Librarian, College of Medicine, The University of Edinburgh) for assistance in developing the initial search strategy.
We are grateful to authors (Armstrong, Da Costa, Daley, Foley, Hess-Homeier, Kerse, Mead, Mota-Pereira, Mutrie, and Nguyen) and Professors Grant Schofield and David French for personal communications and providing us with manuscripts, additional information and data.
We also thank Marion Brady, Glasgow Caledonian University, for
References1 (70)
- et al.
A commentary on ‘Exercise and Depression’: and the verdict is……
Mental Health and Physical Activity
(2009) - et al.
Comparative efficacy and acceptability of 12 new-generation antidepressants: a multiple-treatments meta-analysis
The Lancet
(2009) Risk factors and predictors of compliance in depression
European Neuropsychopharmacology
(2003)- et al.
Exercise for depression
Mental Health and Physical Activity
(2009) - et al.
Moderate exercise improves depression parameters in treatment-resistant patients with major depressive disorder
Journal of Psychiatric Research
(2011) - et al.
Depression, chronic diseases, and decrements in health: results from the World Health Surveys
The Lancet
(2007) - et al.
Change in self-esteem, self-efficacy and the mood dimensions of depression as potential mediators of the physical activity and depression relationship: exploring the temporal relation of change
Mental Health and Physical Activity
(2009) 10,000 steps
(2011)- et al.
The effects of exercise and social support on mothers reporting depressive symptoms: a pilot randomized controlled trial
International Journal of Mental Health Nursing
(2003) - et al.
The effectiveness of a pram-walking exercise programme in reducing depressive symptomatology for postnatal women
International Journal of Nursing Practice
(2004)
The effect of a pedometer-based community walking intervention “Walking for Wellbeing in the West” on physical activity levels and health outcomes: a 12-week randomized controlled trial
International Journal of Behavioral Nutrition and Physical Activity
Which clinical studies provide the best evidence? The best RCT still trumps the best observational study
BMJ
Genomic predictors of the maximal O uptake response to standardized exercise training programs
Journal of Applied Physiology
Using pedometers to increase physical activity and improve health: a systematic review
JAMA
Exercise and the treatment of clinical depression in adults: recent findings and future directions
Sports Medicine
Kids walk to school
Tripartite model of anxiety and depression: psychometric evidence and taxonomic implications
Journal of Abnormal Psychology
The benefits of exercise for the clinically depressed
Primary Care Companion. Journal of Clinical Psychiatry.
Exercise and depression: a review of reviews
Journal of Clinical Psychology in Medical Settings
Physical activity in the process of psychiatric rehabilitation: theoretical and methodological issues
Psychiatry and Rehabilitation Journal
Older patients’ aversion to antidepressants
Journal of General and Internal Medicine
Cost-utility of a walking programme for moderately depressed, obese, or overweight elderly women in primary care: a randomised controlled trial
BMC Public Health
Restorative effects of natural environment experiences
Environment and Behaviour
Physical activity
Concurrent and prospective associations between physical activity, walking and mental health in older women
J Epidemiol. Community Health
Putting trials on trial–the costs and consequences of small trials in depression: a systematic review of methodology
Journal of Epidemiology & Community Health
Walk to a healthy future
The experience of nature: A psychological perspective
Depressive and bipolar disorders: patients’ attitudes and beliefs towards depression and antidepressants
Psychological Medicine
Effects of differing intensities and formats of 12 months of exercise training on psychological outcomes in older adults
Health Psychology
Initial severity and antidepressant benefits: a meta-analysis of data submitted to the food and drug administration
PLoS Medicine
A randomised, controlled study on the effects of a short-term endurance training programme in patients with major depression
British Journal of Sports Medicine
The effect of exercise in clinically depressed adults: systematic review and meta-analysis of randomized controlled trials
Journal of Clinical Psychiatry
The effectiveness of exercise as an intervention in the management of depression: systematic review and meta-regression analysis of randomised controlled trials
BMJ
Cited by (158)
Changes in walking practice and associated factors during the coronavirus disease 2019 pandemic
2023, Preventive Medicine ReportsSports practice, walking and biking are positively related to quality of life in adults: A cross-sectional study
2023, Journal of Transport and HealthContext matters: A review of reviews examining the effects of contextual factors in physical activity interventions on mental health and wellbeing
2023, Mental Health and Physical ActivityOptimising the effects of physical activity on mental health and wellbeing: A joint consensus statement from Sports Medicine Australia and the Australian Psychological Society
2023, Journal of Science and Medicine in Sport
- 1
References marked with an asterisk indicate studies included in the meta-analysis.