Effects of different exercises on psychological anxiety and depression in patients with chronic obstructive pulmonary disease: a systematic review and meta-analysis

Introduction

Chronic obstructive pulmonary disease (COPD) is defined as a chronic respiratory disease characterised by persistent airflow limitation and respiratory symptoms and is often accompanied by comorbidities, such as heart failure, osteoporosis, anxiety and depression, which severely affect patients’ cure rate, mortality and quality of life (1). The Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines emphasise that anxiety and depression (2), as common yet frequently underdiagnosed comorbidities of COPD, not only are closely associated with poor health status and prognosis but also considerably diminish patients’ quality of life and treatment adherence by inducing low mood (3-5). The prevalence of anxiety in patients with COPD ranges from 10% to 55%, and that of depression ranges from 7% to 42%. Concurrently, 26–43% of patients experience both conditions. The prevalence of these mental health issues correlates positively with disease severity, and patients with severe COPD are twice as likely to develop depression as those with mild disease (6-8). In clinical settings, the physical symptoms of COPD, such as breathlessness and coughing, frequently obscure the presence of anxiety and depression, leading to these conditions being under-recognised by patients, their families and even clinicians (9,10). Consequently, the actual prevalence of anxiety and depression in patients with COPD may be higher than previously estimated, necessitating heightened awareness and the development of effective intervention strategies.

Currently, primary interventions addressing mental health issues in patients with COPD comprise pharmacological treatment and cognitive behavioural therapy. Although medication is widely employed, its efficacy remains inconclusive and is frequently accompanied by pronounced side effects, such as somnolence and nausea (11-14). Moreover, although cognitive behavioural therapy demonstrates positive short-term outcomes, its long-term benefits remain contentious, and its reliance on specialist resources limits its clinical accessibility (15-17). Exercise is regarded as an effective treatment for mental health (18), not only alleviating physiological strain by enhancing respiratory muscle function and relieving breathlessness but also exerting a positive regulatory effect on emotional states. It delivers physiological and psychological benefits and is readily adaptable to diverse settings (19). However, information about the mental health effects of exercise interventions for patients with COPD is limited. Current assessment tools and metrics yield inconsistent results, which are difficult to compare, with considerable variation in exercise intervention formats, intensities and durations resulting in high heterogeneity and meta-analyses concerning the psychological effects of exercise have primarily focused on mind-body exercises and neglected other forms (20). Although exercise has been increasingly recognized as an effective non-pharmacological strategy for improving both physical and psychological health in patients with COPD, several important questions remain unresolved. A recent systematic review and meta-analysis by Liu et al. comprehensively summarized the beneficial effects of exercise on psychological distress in patients with COPD (21). However, several limitations of the existing evidence warrant further investigation. First, previous reviews primarily synthesized overall psychosocial outcomes, including anxiety, depression, emotion regulation and self-efficacy, without specifically focusing on anxiety and depression, which are the two most prevalent and clinically significant psychological comorbidities in COPD. Consequently, evidence regarding the effectiveness of exercise on these core mental health outcomes remains insufficiently targeted. Second, previous studies generally categorized exercise interventions into relatively broad groups, which may have obscured potential differences in treatment effects among specific exercise modalities. A more detailed classification of exercise interventions may provide greater clinical insight for selecting appropriate exercise prescriptions. Finally, although substantial heterogeneity has been reported across studies, previous reviews have paid limited attention to clinically meaningful sources of heterogeneity, particularly whether baseline severity of anxiety and depression influences the psychological response to exercise interventions. Identifying patient subgroups that derive the greatest benefit from exercise may improve individualized clinical decision-making.

Therefore, the present systematic review and meta-analysis aimed to provide an updated synthesis of randomized controlled trials (RCTs) by incorporating recently published evidence, focusing specifically on anxiety and depression, performing detailed subgroup analyses according to exercise modality and baseline symptom severity, and offering a more comprehensive interpretation of methodological quality and heterogeneity. We hypothesized that exercise interventions would significantly improve anxiety and depression in patients with COPD and that these benefits might differ according to exercise type and baseline psychological status. We present this article in accordance with the PRISMA reporting checklist (available at https://jtd.amegroups.com/article/view/10.21037/jtd-2026-1371/rc) (22).

Methods

Study design

This study was registered on PROSPERO (CRD42025649637).

Data sources

On 16 June 2026, two researchers (J.Z. and B.L.) conducted a comprehensive search of English databases (PubMed, Embase, Cochrane Library, Web of Science, SPORTDiscus and PsycINFO) to identify relevant studies. The search terms included ‘exercise training’, ‘COPD’, ‘anxiety’, ‘depression’ and ‘RCT’, as well as free terms such as ‘exercise’, ‘physical activity’, ‘chronic obstructive pulmonary disease’, ‘chronic obstructive lung disease’, ‘cognitive function’, ‘Tai Chi’, ‘swimming’, ‘walking’, ‘breathing exercises’, ‘Baduanjin’, ‘Liuzijue’, ‘randomized controlled trial’ and ‘respiratory training’. Studies published from the inception of the databases to 16 June 2026 were considered. Detailed search information is provided in Appendix 1.

Inclusion and exclusion criteria

Inclusion criteria: (I) participants must meet the COPD diagnostic criteria in the GOLD guidelines (2); (II) interventions are any form of exercise training, including aerobic exercise, resistance exercise, strength training, dance, singing and fitness qigong; (III) The control group receives health education or routine care; (IV) research findings must include measurements of anxiety or depression; (V) RCTs; (VI) studies described as pilot trials were included only when they were designed as RCTs.

Exclusion criteria: (I) duplicate studies; (II) conference papers and other studies lacking full text; (III) studies with missing or unclear trial data.

Study selection and data extraction

Two researchers independently performed literature screening, data extraction and cross-checking. Information extracted included first author, publication year, participant characteristics, intervention frequency, duration per session, intervention duration outcome measurements, and sample sizes, and the mean values and standard deviations (SDs) at baseline and post-intervention or the corresponding change scores, where available. Search results were imported and downloaded using Endnote 21 software. Discrepancies in risk assessment were resolved through discussion or by a third researcher.

Quality assessment and certainty of evidence

The quality of studies was evaluated using Cochrane Bias Risk Assessment Tool RoB2.0 (23). RoB2.0 assesses bias in five domains: randomisation, deviation from the intended intervention, missing outcome data, outcome measurement and outcome reporting. The tool provides five response options: yes, probably yes, probably no, no and unclear. Each domain is rated as high risk, some concerns or low risk. Discrepancies were resolved through discussion. When inconsistencies persisted, solutions were sought by discussing with another researcher. To evaluate the certainty of evidence, the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach was employed. This framework assesses the quality of evidence across five domains: risk of bias, inconsistency, indirectness, imprecision, and publication bias. The evidence is then classified into four categories: high, moderate, low, or very low certainty (24).

Measures of treatment effect

Treatment effects were analysed using standardized mean differences (SMDs) calculated from change scores. When change-score SDs were unavailable, they were derived from standard errors (SEs), 95% confidence intervals (CIs), P values, or t statistics according to the Cochrane Handbook (25). If change-score SDs could not be obtained, they were estimated using an assumed correlation coefficient of 0.5, representing moderate within-subject correlation (25).

Statistical analysis

This study used Stata 18.0 software for meta-analysis, and the combined effect size of exercise intervention versus routine control on the mental health of patients with COPD was visualised using forest plots. Sensitivity analyses and publication bias analyses were then conducted. Given that included studies used different assessment tools for the same outcome indicators and the data were continuous variables, the effect size was uniformly expressed as SMD and its 95% CI. An I² value of <50% indicated low heterogeneity. Therefore, a fixed-effects model was adopted. An I² of ≥50% indicated high heterogeneity, and a random-effects model was adopted. For studies with high heterogeneity, sources of heterogeneity were explored. For studies with low heterogeneity, main regulatory factors affecting effects were identified. Difference in response regarding intervention effects among different clinical characteristic subgroups were determined through subgroup analyses.

Measurement of anxiety and depression

Anxiety and depression were assessed using validated psychometric instruments. The included studies used several commonly applied scales to evaluate these outcomes. Anxiety was primarily assessed using the Hospital Anxiety and Depression Scale-Anxiety subscale (HADS-A) (26), the Self-rating Anxiety Scale (SAS) (27), the Hamilton Anxiety Rating Scale (HAMA) (28), and the Beck Anxiety Inventory (BAI) (29). Depression was primarily assessed using the Hospital Anxiety and Depression Scale-Depression subscale (HADS-D) (26), The Center for Epidemiologic Studies Depression Scale (CES-D) (30), and the Beck Depression Inventory (BDI) (31),

Results

Search results

The search results were imported into EndNote 21 software, yielding a total of 2,229 articles. After duplicates were removed, 1,354 articles remained. After the abstracts and titles were reviewed, 1,242 articles were excluded. The remaining 112 articles were further screened by reading the full text, and 94 studies were excluded because of irrelevance or missing data. Finally, 18 eligible studies were included in the meta-analysis (Figure 1).

Figure 1 Flow of study selection.

Characteristics of eligible studies

A total of 18 eligible RCTs were included, which were conducted in Türkiye (32-37), China (38-42), UK (43,44), Austria (45), Sweden (46), USA (47), Australia (48) and Spain (49) (Table 1). A total of 1,034 subjects were included: 514 in the exercise group and 520 in the control group. The maximum sample size was 160 (39), and the minimum sample size was 5 (47). The intervention was performed for 4–24 weeks, 2–7 times a week and 20–60 min each time. Among the 18 RCTs, 6 investigated breathing exercises (32,33,37,41,43,49); 5, traditional Chinese exercises (39,40,42,47,48); 3, singing (35,38,44); 1, water-based exercise (34); 1, resistance exercise (46); 1, calisthenic exercise (36); and 1, walking exercise (45).

Methodological quality assessment

The results of the Cochrane bias risk assessment are shown in Figure 2. All studies had complete outcome data, with a low risk of missing data. Among the included studies, only ten implemented assessor blinding. The remaining studies had unclear outcome measurement bias, potentially resulting in detection bias. Five studies did not appropriately concealed the allocation sequence. Given that the intervention type in all studies was exercise, double-blinding was unfeasible. Therefore, bias risk assessment should be considered in the interpretation of the treatment-control analysis results. Funnel plots, sensitivity analyses and Egger’s regression test confirmed the absence of publication bias in this study (Figures S1-S6). The GRADE evaluation indicated low certainty for the evidence supporting the effects of exercise interventions on depression and anxiety symptoms (Table 2).

Figure 2 Analysis of the risk of bias in accordance with the Cochrane collaboration guidelines: (A) traffic light plot of bias assessment and (B) weighted summary plot of overall type of bias.

Results of meta-analysis

Effect of exercise on anxiety and depression in patients with COPD

Of the 18 included articles, 16 described the anxiety scores and 15 reported the depression scores of the exercise and control groups before and after treatment. As shown in Figure 3, the meta-analysis results showed that compared with routine care, exercise intervention had significantly alleviated psychological anxiety (SMD =−0.85; 95% CI: −1.16 to −0.53, P<0.001, I²=78.2%). As shown in Figure 4, compared with routine care, exercise intervention had significantly alleviated psychological depression (SMD =−0.77; 95% CI: −1.11 to −0.44, P<0.001, I²=77.7%).

Figure 3 Effect of exercise on anxiety. According to the forest plot results, exercise intervention significantly reduces anxiety levels in COPD patients. CI, confidence interval; COPD, chronic obstructive pulmonary disease; DL, DerSimonian-Laird.

Figure 4 Effect of exercise on depression. According to forest plot results, exercise intervention significantly reduces depression levels in COPD patients. CI, confidence interval; COPD, chronic obstructive pulmonary disease; DL, DerSimonian-Laird.

Subgroup analysis

Exploratory subgroup analyses according to exercise modality were performed to explore potential sources of heterogeneity. Significant reductions in anxiety were observed in the aerobic and traditional Chinese exercise subgroups, whereas the resistance exercise subgroup did not reach statistical significance (SMD =−0.34; 95% CI: −0.93 to 0.26). Because several exercise-type subgroups included only one or a few studies, these findings should be interpreted as exploratory rather than confirmatory. Larger effect estimates were observed across subgroups defined by exercise duration per session, exercise frequency, intervention cycle, exercise intensity and anxiety level. Although statistically significant differences were observed among anxiety-severity subgroups (P<0.01), the severe-anxiety subgroup was represented by only one study, and therefore this finding should be interpreted with caution (Table 3).

For depression, Table 4 indicates that when exercise mode was used as a subgroup, aerobic exercise and traditional Chinese exercises had a significant effect on depression, whereas resistance exercise (SMD =−0.43; 95% CI: −1.03 to 0.16) did not. Because several exercise-type subgroups included only one or a few studies, these findings should be interpreted as exploratory rather than confirmatory. Only low-to-moderate intensity exercise had a significant effect on the outcome, whereas high-intensity exercise showed no significance (SMD =−0.79; 95% CI: −1.58 to 0.00). When grouped by exercise duration per session, exercise frequency, intervention cycle and depression level, interventions showed significant effect estimates. Although statistically significant differences were observed among depression-severity subgroups (P<0.01), the severe-depression subgroup was represented by only one study, and therefore this finding should be interpreted with caution.

Discussion

This study aimed to explore the effect of exercises on anxious and depressed patients with COPD to determine the optimal exercise training programme. Symptoms of anxiety and depression frequently overlap with those of COPD, leading to delayed treatment (50). Therefore, alleviating anxiety and depression in patients with COPD is important. The results show that exercise is an effective strategy to alleviate psychological comorbidity in patients with COPD.

The findings of this study are highly consistent with existing literature on the alleviation of anxiety and depression through exercise. An RCT conducted by Lin et al. showed that respiratory walking training significantly reduced anxiety and depression scores and improved quality of life in patients with COPD (19), which is consistent with the results of this meta-analysis. Additionally, a meta-analysis by Heissel et al. (18) on the general population indicated that exercise (aerobic or resistance training) has a clear effect on depressive symptoms, and the results of this study on depression in patients with COPD further extend the applicability of this conclusion to the COPD population. In contrast to the meta-analysis by Li et al. (20), this meta-analysis synthesises the effects of all forms of exercise on the mental health of patients with COPD, rather than focusing solely on mind-body exercises. This study allows for advanced clinical decision-making, which includes whether to incorporate exercise and how to select optimal exercise programme. Compared with Liu et al. (21), our pooled estimates similarly demonstrated that exercise significantly alleviated anxiety and depression in patients with COPD, supporting the robustness of previous evidence. However, unlike previous reviews that synthesized multiple psychosocial outcomes, our review specifically focused on anxiety and depression, providing a more clinically targeted evaluation. More importantly, our subgroup analyses demonstrated that patients with severe baseline anxiety or depression experienced larger improvements following exercise interventions. This clinically relevant finding was not investigated in previous reviews. Thus, it provides actionable and differentiated evidence for the non-pharmacological management of psychological comorbidities in patients with COPD.

Notably, subgroup analysis results show that aerobic exercise and traditional Chinese exercises of any frequency, cycle, duration and intensity alleviate anxiety in patients with COPD. This universal efficacy may stem from the multidimensional mechanisms of action inherent in such exercises. At their core lies mind-body integration, which is achieved through gentle physical movements combined with rhythmic breathing techniques. On the one hand, this exercise regulates autonomic nervous system balance; on the other hand, it alleviates ‘breath anxiety’ by improving perceptions of breathlessness. Concurrently, these exercises reduce systemic inflammation levels (51,52). For depression, aerobic exercises and traditional Chinese exercises of any frequency and low-to-moderate intensity with any cycle and duration alleviate depression in patients with COPD. This effect may be attributable to multiple complex mechanisms in the neurobiological basis of depression, including alterations in brain structure, abnormalities in neurotransmitter systems, inflammatory responses and immune reactions (53-55). Moderate-to-low intensity exercises are well tolerated and adhered to by patients, minimising the risk of excessive fatigue and negative emotions that may be associated with high-intensity exercises. This finding is particularly important for patients with COPD, who already have exercise limitations. However, the subgroup analyses according to exercise modality should be interpreted cautiously. Although these analyses suggested potential differences among exercise modalities, several exercise-type subgroups were represented by only one or a few studies. Consequently, these findings should be regarded as exploratory rather than definitive evidence of the comparative effectiveness of different exercise modalities. Future well-designed RCTs comparing specific exercise modalities are needed to verify these preliminary findings. Moreover, exercise is more effective for patients with COPD with high levels of anxiety and depression. At the psychological level, patients experiencing severe emotional distress initially exhibit low quality of life (56). The benefits of exercise, such as enhanced physical functioning and increased self-efficacy, are more pronounced in this group. Moreover, sporting activities themselves provide social support and a regular daily rhythm, which holds particular psychological value for individuals with severe conditions (57).

These results suggest that long-term regular exercise may improve mental health by regulating the neuroendocrine system and metabolic status (58). Given that this meta-analysis confirms the positive effect of exercise training on the mental health of patients with COPD, future RCTs should go beyond verifying effectiveness and instead optimise training prescription design to maximise mental health benefits.

On Heterogeneity, our subgroup analyses revealed that anxiety and depression levels were significant sources of heterogeneity in the meta-analysis. For anxiety, the high overall heterogeneity (I²=78.2%) was substantially reduced in moderate and severe subgroups (I²=0%), with a significant interaction effect (P<0.01). Similarly, for depression, severity-based subgroups showed distinct effects. This result indicates that variability in exercise efficacy is partly explained by baseline mental health status, supporting the need for personalised intervention strategies.

This study has several limitations. Although the present meta-analysis suggests that exercise interventions improve anxiety and depression in patients with COPD, the certainty of evidence was rated as low according to the GRADE framework. This was primarily driven by methodological limitations in the included RCTs and considerable heterogeneity. Therefore, the findings should be interpreted with caution, and future high-quality trials are required to confirm these results. Most studies employed the HADS as an assessment tool, and few utilised the SAS, HAMA, BAI, BDI or CES-D scales. This resulted in variations in the sensitivity of outcome measures across different studies. Furthermore, most studies failed to evaluate subtypes of anxiety and depression, such as generalised anxiety or major depressive disorder, and thus precisely matching the needs of different patient groups was difficult. The order of allocation was unclear in five studies. The allocation order was not properly hidden in five studies, double-blinding could not be implemented because the types of study interventions were all exercise interventions, and assessor blinding was implemented in only ten studies. And variations in study designs and populations were found, and no uniform standards were established for the interpretation of experimental design, frequency, exercise time and duration of exercise. In addition, one study had a relatively small sample size and another had a short intervention duration, limiting the precision and long-term generalizability of the findings. Furthermore, several subgroup analyses, particularly those based on exercise type, were supported by only one or a few studies and should therefore be interpreted as exploratory rather than definitive. This review also has several methodological limitations. Although a comprehensive search strategy was conducted across six major databases, only studies published in English were included, which may have introduced language bias. Grey literature, conference abstracts, and unpublished studies were not included, potentially increasing the risk of publication bias despite the absence of significant asymmetry in statistical tests. Furthermore, although multiple databases were searched, relevant studies indexed in other databases may have been missed. Finally, the subgroup analyses were exploratory in nature and were not prespecified to formally test treatment-effect modifiers; therefore, these findings should be interpreted cautiously.

Conclusions

Overall, exercise training exerts a positive influence on the mental health of patients with COPD, and increased efficacy was observed in patients with high levels of anxiety and depression. However, owing to limitations in experimental design and the clinical neglect of mental health in COPD management, RCTs with higher quality are required to substantiate the efficacy of exercise in improving the mental wellbeing of patients with COPD.

Acknowledgments

None.

Footnote

Reporting Checklist: The authors have completed the PRISMA reporting checklist. Available at https://jtd.amegroups.com/article/view/10.21037/jtd-2026-1371/rc

Peer Review File: Available at https://jtd.amegroups.com/article/view/10.21037/jtd-2026-1371/prf

Funding: This work was directly supported by the National Natural Science Foundation of China (grant No. 82372573), and Health Discipline Leader Project of Shanghai Municipal Health Commission (grant No. 2022XD044).

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://jtd.amegroups.com/article/view/10.21037/jtd-2026-1371/coif). X.L. reports support from the National Natural Science Foundation of China and Health Discipline Leader Project of Shanghai Municipal Health Commission. The authors have no other conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

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