Is Exercise an Efficacious Treatment for Depression? A Comment upon Recent Negative Findings

Personality and Its Influence on Pain Sensitivity Based on Different Hormonal Responses to Individual vs. Group Exercise Styles

Individual differences in pain sensitivity are thought to relate to personality traits, but the underlying mechanisms remain unclear. Exercise influences hormonal secretion via the hypothalamic-pituitary system, which may link personality, hormonal responses, and pain perception. This study investigated these relationships in 14 healthy participants (3 females, 11 males, aged 20-50 years, mean 28 ± 9.25 years). Participants rated thermal pain stimuli and completed the NEO Personality Inventory-Revised (NEO-PI-R) to identify their personality. Each participant engaged in personal and group training sessions, with blood samples collected to measure cortisol, growth hormone, and other indicators. Participants were clustered into cortisol hypersecretors and hyposecretors based on their hormonal response. Hypersecretors exhibited significantly lower neuroticism scores and pain ratings than hyposecretors. These findings suggest a potential association between cortisol responsiveness during exercise, neuroticism, and pain sensitivity. This study highlights potential links between personality traits and reactive hormonal patterns, offering insights into the psychophysiological mechanisms underlying pain expression.

Physical Activity and Depression in Adolescents: Evidence from China Family Panel Studies

Depression in adolescents is a major public health disorder. The relationship between physical activity and risk of depression in adolescents was examined using three waves of data from the China Family Panel Studies in 2020. The risk of depression was significantly higher among adolescents who reported lower frequency and shorter duration of physical exercise than those who reported physical exercise more frequently and for a longer duration. The risk of depression was significantly higher among adolescents who reported intense physical exercise than those who reported little or no intense physical exercise. The amount of time spent on housework by adolescents is inversely associated with depression. These results provide somewhat stronger evidence for an activity−depression link than previous studies and suggest a differential role for different types of physical activity, such as exercise and housework. The overall model predicting depression in adolescents (LR chi-squared = 95.974, p < 0.001, Nagelkerke R-square = 0.183) was statistically significant. To effectively control depression in adolescents, the government, schools and parents need to act together to guide adolescents towards participation in appropriate physical activities. The appropriate level of physical activity is for adolescents to experience breathing, rapid heartbeat, and slight perspiration.

Effectiveness of Physical Exercise in Older Adults With Mild to Moderate Depression

PURPOSE

We sought to compare the effectiveness of physical exercise with that of treatment with antidepressant drugs routinely used in clinical practice, in terms of decreasing depressive symptomatology in patients aged ≥65 years who present with clinical criteria of a depressive episode.

METHODS

We conducted a randomized clinical trial in a primary care setting. A total of 347 patients aged ≥65 years with a clinically significant depressive episode were randomized to participation in a supervised physical exercise program or to receive antidepressant treatment by their general practitioners.

RESULTS

Intention-to-treat analysis showed that the cumulative incidence of improvement in depressive symptomatology (Montgomery-Åsberg Depression Rating Scale score <10) in the physical activity (PA) group after 1 month was not significantly different from that in the antidepressant treatment (AT) group. However, the proportion of those who showed improvement was significantly greater (P <.01) in the AT group (60.6% and 49.7%) compared to the PA group (45.6% and 32.9%) at the end of 3 and 6 months, respectively. The number of withdrawals was greater in the PA group (39.2% and 58.2%) compared to the AT group (22.6% and 40.0%) at 3 and 6 months, respectively, yet the proportion of participants with adverse side effects was greater in the AT group (8.9% vs 22.5%; P = .007).

CONCLUSION

Although improvement was initially similar in both treatment groups, AT was superior in the medium term, despite giving rise to a greater number of adverse effects.

Effectiveness of physical exercise in the treatment of depression in older adults as an alternative to antidepressant drugs in primary care

BACKGROUND

Although currently available evidence suggests that physical exercise can be beneficial for depressed patients and might be comparable to antidepressant treatment, the best way of implementing this recommendation in clinical practice is not known. This study therefore aims to ascertain the non-inferiority of supervised physical exercise to antidepressant drug treatment, in terms of reducing depressive symptoms among patients presenting with clinical criteria of a depressive episode (ICD-10), across a follow-up period of 6 months.

METHODS

It will take the form of a randomised clinical trial undertaken in a primary care setting, in which a total of 312 patients over the age of 65 years with clinically significant depression will be randomly assigned to supervised physical exercise programme, or will alternatively receive treatment with antidepressant drugs habitually used in clinical practice. Participants' physical condition will be assessed at baseline, and again at 15 days and 1, 3 and 6 months. The supervised exercise programme will consist of 2 weekly sessions in groups of 10-12 patients across a period of 6 months, in which a sports instructor will train patients to do at least 30 min of regular activity at moderate intensity on an almost daily basis, including aerobic, muscle-strengthening, flexibility, and balance-strengthening exercises. The following will be assessed at regular intervals in both groups: status of depression symptoms; level of physical activity; self-perceived health status; appearance of adverse effects; and adherence to the physical exercise programme or antidepressant treatment. The principal outcome variable will be a reduction in pre-treatment depression-symptom scale scores (Montgomery-Asberg Depression Rating Scale and Geriatric Depression Scale).

DISCUSSION

In terms of the number of patients and duration of follow-up, this proposed clinical trial is a project which easily surpasses the few studies on this subject that have been previously conducted on the elderly. Its aim is to provide solid scientific evidence on a therapeutic resource -physical exercise- which has undeniable health benefits and can be applied to certain health problems, such as depressive disorders, which are of great magnitude and considerable socio-economic relevance, and have a significant impact on the quality of life of older adults.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03358433 (retrospectively registered on 11/25/2017).

Effects of Exercise on Mild-to-Moderate Depressive Symptoms in the Postpartum Period: A Meta-analysis

OBJECTIVE

To examine the influence of exercise on depressive symptoms and the prevalence of depression in the postpartum period.

DATA SOURCES

A structured search of MEDLINE, EMBASE, CINAHL, Sport Discus, Ovid's All EBM Reviews, and ClinicalTrials.gov databases was performed with dates from the beginning of the databases until June 16, 2016. The search combined keywords and MeSH-like terms including, but not limited to, "exercise," "postpartum," "depression," and "randomized controlled trial."

METHODS OF STUDY SELECTION

Randomized controlled trials comparing postpartum exercise (structured, planned, repetitive physical activity) with the standard care for which outcomes assessing depressive symptoms or depressive episodes (as defined by trial authors) were assessed. Trials were identified as prevention trials (women from the general postpartum population) or treatment trials (women were classified as having depression by the trial authors). Effect sizes with 95% confidence intervals (CIs) were calculated using Hedges' g method and standardized mean differences in postintervention depression outcomes were pooled using a random-effects model.

TABULATION, INTEGRATION, AND RESULTS

Across all 16 trials (1,327 women), the pooled standardized mean difference was -0.34 (95% CI -0.50 to -0.19, I=37%), suggesting a small effect of exercise among all postpartum women on depressive symptoms. Among the 10 treatment trials, a moderate effect size of exercise on depressive symptoms was found (standardized mean difference-0.48, 95% CI -0.73 to -0.22, I=42%). In six prevention trials, a small effect (standardized mean difference-0.22, 95% CI -0.36 to -0.08, I=2%) was found. In women with depression preintervention, exercise increased the odds of resolving depression postintervention by 54% (odds ratio 0.46, Mantel-Haenszel method, 95% CI 0.25-0.84, I=0%). The trials included in this meta-analysis were small and some had methodologic limitations.

CONCLUSION

Light-to-moderate intensity aerobic exercise improves mild-to-moderate depressive symptoms and increases the likelihood that mild-to-moderate depression will resolve.

Challenges Establishing the Efficacy of Exercise as an Antidepressant Treatment: A Systematic Review and Meta-Analysis of Control Group Responses in Exercise Randomised Controlled Trials

BACKGROUND

Whilst previous meta-analyses have demonstrated that control group responses (CGRs) can negatively influence antidepressant efficacy, no such meta-analysis exists in exercise randomised controlled trials (RCTs).

OBJECTIVE

The aim of this study was to conduct a systematic review and meta-analysis investigating CGRs and predictors in control groups of exercise RCTs among adults with depression.

METHODS

Three authors acquired RCTs from a previous Cochrane review (2013) and conducted updated searches of major databases from January 2013 to August 2015. We included exercise RCTs that (1) involved adults with major depressive disorder (MDD) or depressive symptoms; (2) measured depressive symptoms pre- and post-intervention using a validated measure [e.g. Hamilton Depression Scale (HAM-D)]; and (3) included a non-active control group. A random effects meta-analysis calculating the standardised mean difference (SMD) together with 95 % confidence intervals (CIs) was employed to determine CGR.

RESULTS

Across 41 studies, 1122 adults with depression were included [mean (SD) age 50 (18) years, 63 % female]. A large CGR of improved depressive symptoms was evident across all studies (SMD -0.920, 95 % CI -1.11 to -0.729). CGRs were elevated across all subgroup analyses, including high quality studies (n = 11, SMD -1.430, 95 % CI -1.771 to -1.090) and MDD participants (n = 18, SMD -1.248, 95 % CI = -1.585 to -0.911). The CGR equated to an improvement of -7.5 points on the HAM-D (95 % CI -10.30 to -4.89). In MDD participants, increasing age moderated a smaller CGR, while the percentage of drop-outs, baseline depressive symptoms and a longer control group duration moderated a larger CGR (i.e. improvement) (p < 0.05).

CONCLUSION

In order to demonstrate effectiveness, exercise has to overcome a powerful CGR of approximately double that reported for antidepressant RCTS.

A critical review of exercise as a treatment for clinically depressed adults: time to get pragmatic

OBJECTIVE

Although considerable evidence supports the efficacy of exercise as an antidepressant treatment, critical reviews informing routine practice and future research directions are scarce.

METHODS

We critically reviewed exercise studies for clinically depressed adults, focussing on the PICOS criteria referred to participants, interventions, comparisons, outcomes, and study designs.

RESULTS

Most studies have not screened their samples for symptom heterogeneity. Also, they have employed heterogeneous exercise interventions and control groups that may lead to an underestimation of the benefits of exercise. In addition, pragmatic trials allowing scalable replication and implementation in routine practice are scarce. Future studies, can consider the research domain criteria as a diagnostic framework, and conduct moderator analyses to identify depressed subgroups with symptomatology and biopsychosocial characteristics associated with differential responses to exercise interventions. The search for biomarkers of the antidepressant responses to exercise should be prioritised. Further, non-physically active comparison groups should be used to minimise treatment cross-overs and thus the underestimation of the effects of exercise interventions. Finally, the use of outcome measures that maintain their validity at low and moderate levels of symptom severity and the development of trials with a pragmatic design are essential.

CONCLUSION

The current evidence base is fraught with methodological considerations that need to be taken into account in order to increase further our understanding on the impact of exercise as medicine in depression. Future research should include moderator analyses, incorporate biomarker assays, use appropriate control and comparison groups, assess outcomes with psychometrically sensitive measures, and prioritise pragmatic trials towards transition to routine practice.

Atypical depressive symptoms as a predictor of treatment response to exercise in Major Depressive Disorder

Effective treatment of Major Depressive Disorder (MDD) will require the development of alternative treatments and the ability for clinicians to match patients with the treatment likely to produce the greatest effect. We examined atypical depression subtype as a predictor of treatment response to aerobic exercise augmentation in persons with non-remitted MDD. Our results revealed a small-to-moderate effect, particularly in a group assigned to high-dose exercise (semi-partial eta-squared =0.0335, p=0.0735), indicating that those with atypical depression tended to have larger treatment response to exercise. Through this hypothesis-generating analysis, we indicate the need for research to examine depression subtype, along with other demographic, clinical and biological factors as predictors of treatment response to exercise.

Moderators of response in exercise treatment for depression: A systematic review

INTRODUCTION

Exercise have antidepressant effects in people with Major Depressive Disorder (MDD). However, about to half of patients do not respond to exercise. The identification of factors that moderates the antidepressant effects of exercise in people with MDD may help researchers and health professionals to identify sub-groups of patients that would benefit more from exercise.

METHODS

A systematic review was carried out using Medline(PubMed), EMBASE and psycINFO up to April 2015. Individual and composite moderators were summarized and the strength of the evidence was assessed.

RESULTS

Eleven studies were included for review resulting in the identification of potential individual (two biological, three clinical, two psychological and two social individual) and two potential composite moderators (the interaction between BDNF and Body Mass Index (BMI) and between family history of mental illness and gender). Only the two biological features and the BDNF x BMI interaction provided confirmatory evidence.

LIMITATIONS

Due the different statistical approaches used in the studies, it was not possible to perform meta-analyses. The small number of studies and the exploratory nature of the evidence limits a wider generalization of the findings.

CONCLUSION

Potential clinical, psychological, social or biological moderators were identified. However, the small number of studies and the limited strength of the evidence requires further studies before drawn definitive results. Further trials should consider the inclusion of moderators analysis using an a-priori, theoretical/evidence based hypothesis in order to provide high quality evidence for the use of personalized medicine in exercise for depression.

Effects of structured exercise and pharmacotherapy vs. pharmacotherapy for adults with depressive symptoms: A randomized clinical trial

OBJECTIVE

Physical exercise has been consistently documented as a complementary therapy in the treatment of depressive disorders. However, despite a higher prevalence among women compared to men, the trials developed in women are scarce. In addition, the optimal dosage of exercise capable of producing benefits that reduce depressive symptoms remains unclear. This clinical trial is designed to measure the effect of a structured physical exercise program as a complement to antidepressant medication in the treatment of women with depression.

METHODS

From July 2013 to May 2014, we implemented a randomized controlled trial (HAPPY BRAIN study). A total of 26 women (aged 50.16 ± 12.08) diagnosed with clinical depression were randomized either to a supervised aerobic exercise group (45-50 min/week three times a week for four months) plus pharmacotherapy (intervention group), or only antidepressant medication (control group).

RESULTS

The exercise group presented a decrease in BDI-II and DASS-21 total score scales. Relatively to DASS-21, it showed a significant decrease in anxiety and stress. The exercise group when compared to a control group showed improvement in relation to physical functioning parameters between baseline and post-intervention. Moreover, anthropometric parameters presented only significant differences between groups in fat mass percentage. Nonetheless, no differences were found between groups in weight, body mass index, waist circumference, and self-esteem.

CONCLUSION

Our results showed that supervised structured aerobic exercise training could be an effective adjuvant therapy for treating women with depression, reducing depressive symptomatology and improving physical fitness. A key factor of this improvement included strict control of exercise workload parameters and adjustment to each subject's capacity. In our study, due to the sample size there is an increase in the probability of type II errors.

Exercise and severe major depression: effect on symptom severity and quality of life at discharge in an inpatient cohort

BACKGROUND

Exercise is a potential treatment for depression. However, few studies have evaluated the role of adjunct exercise in the treatment of severely major depressed inpatients. The goal of this study was to evaluate the effects of add-on exercise on the usual treatment of severely depressed inpatients.

METHODS

Fifty participants were randomized to an exercise (exercise + usual treatment) or a control (usual treatment) group. Twenty-five patients were randomly allocated to each group. The participants in the exercise group performed three sessions per week throughout the hospitalization period, with a goal dose of 16.5 kcal/kg/week plus the usual pharmacological treatment. Depressive symptoms and the Quality of Life (QoL) of the participants were assessed at the baseline, the second week, and discharge.

RESULTS

A significant group × time interaction was found for depressive symptoms and the physical and psychological domains of QoL. Differences between groups occurred at the second week and discharge with respect to depressive symptoms and the physical and psychological domains of QoL. There was no difference in the remission rate at discharge (48% and 32% for the exercise and control group, respectively). An NNT of 6.25 was found. No significant baseline characteristics predict remission at discharge.

CONCLUSION

Add-on exercise is an efficacious treatment for severely depressed inpatients, improving their depressive symptoms and QoL. Initial acceptance of exercise remains a challenge.

The effects of exercise on oxidative stress (TBARS) and BDNF in severely depressed inpatients

Exercise can be an effective treatment for depression. Although the efficacy of exercise is well established, little is known concerning the biological changes associated with the antidepressant effects of exercise. A randomized, controlled trial was conducted to evaluate the effects of adding exercise to the usual treatment on the thiobarbituric acid-reactive substances (TBARS) and brain-derived neurotrophic factor (BDNF) serum levels of severely depressed inpatients. Twenty-six participants were randomized to an exercise group (n=15, exercise+treatment as usual) or a control group (n=11, treatment as usual). The participants in the exercise group completed a targeted dose of 16.5 kcal/kg/week of aerobic exercise, three times per week, throughout their hospitalizations. The control group did not exercise during their hospitalizations. The mean hospitalization length was of 21.63 (4.5)×23.82 (5.7) days for exercise and control groups, respectively. The exercise group performed a median of nine sessions. After adjusting for previous tobacco use, a significant group×time interaction was found for TBARS serum levels (p=0.02). A post hoc Bonferroni test revealed differences between the exercise and control groups at discharge. A significant time effect (p<0.001) but no group×time interaction was found (p=0.13) for BDNF serum levels. Adding exercise to the usual treatment of severely depressed inpatients decreases the TBARS serum levels of severely depressed inpatients after 3 weeks. Adding exercise had no additional effects on BDNF serum levels.