Systematic Review of Meta-Analyses: Exercise Effects on Depression in Children and Adolescents

Abstract

Background: Depression is a common threat to children and adolescents in terms of affecting psychosocial development and increasing their risk of suicide. Apart from conventional treatments for depression, physical exercise has become a promising alternative. This paper aims to systematically review the existing meta-analyses that focus on the impact of physical exercise on clinical and nonclinical depression in children and adolescents. Methods: A systematic literature search was conducted using PsycINFO, PsycARTICLES, MedLine, PubMed, and hand searching. Risk of bias analysis, effect sizes calculations, and evaluation of the methodological characteristics (AMSTAR 2) were carried out. Results: Four meta-analyses met the inclusion criteria. After analysing the overlap, the total sample contained 30 single studies (mostly including gender mixed samples) and 2,110 participants (age range 5-20 years). The medium duration of the interventions was 11.5 weeks. The sessions had a medium length of 41 min, and the frequency of implementation was three sessions per week. The most implemented intervention type was aerobic exercise, while control groups mainly continued with their regular routine, among other related options. The overall mean effect of physical exercise on depression was medium (d = −0.50). The additional analysis in clinically depressed samples documented a small to medium mean effect (d = −0.48) in favor of the intervention. Conclusion: The small to medium but consistently positive effects that were found in the present study place physical exercise as a promising and helpful alternative for children and adolescents with clinical and nonclinical depression. The limited literature focused on children and adolescents in comparison with adult samples points to the need for further research.

Effect of Voluntary Exercise Training on Corticosterone Level and Immobility Behavior Induced by Chronic Stress in Rats

“…Extensive research has shown that in depression and other stress-related disorders, BDNF levels in the hippocampus would decrease. However, treatment with chemical antidepressants, electric shock, and exercise increases BDNF [4,13,14,26,29,30]. One of the limitations of the present study was the lack of measurement of related variables such as BDNF.…”

“…After that, voluntary exercise partially improved depression. There have been many studies on the effect of exercise on depression and several mechanisms are involved in this regard [13,14].…”

“…In general, physical activity increases neurotrophins such as Brain-Derived Neurotrophic Factor (BDNF), which increases the neurotransmitters such as serotonin and dopamine. Physical activity also changes the hippocampal structure including volume, dendritic hypertrophy, and neurogenesis, and increases euphoria and social dependence through beta-endorphins [13,20,21].…”

“…It seems that chronic unpredictable stress in the present study caused depression through this mechanism, also there is a positive and significant relationship between serum corticosterone concentration and depressive behavior. Among nervous system-secreting factors, BDNF is one of the most important mechanisms for changes caused by chronic stress and exercise on depression [4,13,14,26]. The central nervous system forms a major part in the control of neural or neuronal plasticity (the ability of the neural network to modulate its structure and function to adapt to environmental inputs), especially during the depression by BDNF.…”

“…So far, many studies have examined various interventions for the treatment of depression [10][11][12]. Various studies have shown that using different types of physical activity may be useful in treating depression [12][13][14]. In depression caused by inactivity, the amount of free radicals and consequently inflammation in the brain increases [15].…”