اثربخشی یوگا درمانی بر کیفیت خواب، سرسختی روان‌شناختی و شادکامی زنان سالمند

Background: With the increasing proportion of older adults in contemporary societies, concerns regarding psychological well-being and the identification of psychological resources that may contribute to improving older adults’ quality of life have become important challenges for mental health professionals. Therefore, the present study aimed to investigate the effectiveness of yoga therapy in improving sleep quality, psychological hardiness, and happiness among older women
Method: The study employed a quasi-experimental pretest–posttest design with a control group. The statistical population consisted of all older women residing in Ahvaz during the first half of 2025. The study sample comprised 30 women aged 65 to 75 years who were selected through convenience sampling based on the study inclusion criteria and randomly assigned to either an experimental or a control group. The experimental group received yoga therapy over a four-week period, with three 60-minute sessions per week. The instruments used in the study were the Pittsburgh Sleep Quality Index, the Kobasa Psychological Hardiness Scale, and the Oxford Happiness Questionnaire. Data were analyzed using univariate analysis of covariance (ANCOVA) in SPSS version 22.
Results: The results showed that, after controlling for pretest scores, significant differences were observed between the experimental and control groups at posttest in sleep quality, psychological hardiness, and happiness (p < .001).
Conclusion: Based on these findings, yoga therapy appears to improve sleep quality, psychological hardiness, and happiness among older women, offering promising potential for psychological interventions and supporting its use as an effective intervention for promoting these outcomes in this population.
EXTENDED ABSTRACT
 Introduction
Aging is a universal and inevitable process that begins at conception and continues throughout the lifespan. All living organisms experience aging, and old age is generally considered to begin after the age of 60. In many countries worldwide, the population growth rate of older adults exceeds that of other age groups. This demographic trend is particularly pronounced among women, whose life expectancy is approximately six to eight years longer than that of men. Accordingly, greater attention to the psychological well-being of older women is warranted. In particular, psychological variables such as sleep quality, psychological hardiness, and happiness may play an important role in maintaining and promoting mental health in later life. Given the numerous challenges faced by older women and the need to identify appropriate and effective interventions for this population, considerable attention should be devoted to interventions and educational programs aimed at promoting their psychological well-being and strengthening the psychological resources required to cope with the stressful experiences associated with aging. To the best of the researchers' knowledge, the effectiveness of yoga therapy in simultaneously improving happiness, sleep quality, and psychological hardiness among older women has not previously been investigated. Therefore, the present study tested the following hypotheses: (1) yoga therapy is effective in improving sleep quality among older women; (2) yoga therapy is effective in enhancing psychological hardiness among older women; and (3) yoga therapy is effective in increasing happiness among older women.
Method
This applied study employed a quasi-experimental pretest-posttest design with a control group. The statistical population consisted of all women aged 65 to 75 years residing in Ahvaz, Iran, during the first half of 2025. Using convenience sampling, 30 older women who met the study eligibility criteria were selected and randomly assigned in equal numbers to an experimental group and a control group. The inclusion criteria were a score above 5 on the Pittsburgh Sleep Quality Index, scores below the mean on the happiness and psychological hardiness measures, age above 65 years, and possession of at least a high-school diploma. The exclusion criteria included simultaneous participation in another therapeutic intervention and the presence of severe cognitive impairment. Data were collected using the Pittsburgh Sleep Quality Index developed by Buysse et al. (1989), the Oxford Happiness Questionnaire developed by Argyle et al. (1989), and the Psychological Hardiness Questionnaire developed by Kobasa et al. (1982). The intervention protocol was adapted from the yoga therapy program developed by Saraswati and Saraswati (1998). The experimental group participated in twelve 60-minute yoga therapy sessions, held three times per week and administered by a psychotherapy specialist. Each session included an introduction to the session objectives and topics, group discussion, and practical exercises. The data were analyzed using univariate analysis of covariance (ANCOVA) in SPSS version 22. The mean age was 67.4 years in the experimental group and 67.2 years in the control group. Ethical considerations included obtaining written informed consent, maintaining the confidentiality of participants' personal information, covering participants' transportation expenses, and providing yoga therapy to the control group after completion of the study.
Results
At pretest, the mean scores for sleep quality, psychological hardiness, and happiness were generally comparable between the experimental and control groups. Following the intervention, however, improvements were observed in all three outcome variables in the experimental group. Given the study design, univariate ANCOVA was used to examine the primary outcomes. Before conducting the analyses, the relevant statistical assumptions were evaluated. Levene's test was used to assess the homogeneity of variances between the two groups. The results were not statistically significant for any of the study variables, indicating that the assumption of homogeneity of variance was satisfied. The assumption of homogeneity of regression slopes was also examined by testing the interaction between group membership and the pretest score for each dependent variable in predicting its corresponding posttest score. The interaction effects were reported as non-significant at the .05 level for sleep quality, psychological hardiness, and happiness. In addition, the Shapiro-Wilk test was used to assess the normality of the dependent variables. The results indicated no statistically significant deviations from normality at the .05 level. Therefore, the assumptions required for conducting ANCOVA were considered to have been met. The results of the univariate ANCOVAs examining the effectiveness of yoga therapy on sleep quality, psychological hardiness, and happiness are presented in Table 1.
The results indicated statistically significant differences between the experimental and control groups in sleep quality, psychological hardiness, and happiness after controlling for the corresponding pretest scores. In other words, compared with the control group, participants in the experimental group demonstrated significant improvements in sleep quality, psychological hardiness, and happiness following the yoga therapy intervention. Therefore, all three study hypotheses were supported.
Conclusion
The present study aimed to investigate the effectiveness of yoga therapy in improving sleep quality, psychological hardiness, and happiness among older women. The findings indicated that yoga therapy contributed to significant improvements in all three outcomes. Yoga techniques may help older adults shift their attention away from merely attempting to eliminate or suppress unpleasant symptoms and toward developing a more meaningful and valued life. Through such practices, individuals may learn to observe and accept their thoughts, emotions, memories, and bodily sensations without judgment or the need to defend themselves against these experiences. Yoga therapy may also promote psychological flexibility by helping older adults become less rigidly governed by their thoughts and internal rules and, instead, develop more adaptive ways of interacting with their environment. The findings suggest that yoga therapy may be regarded as a potentially useful intervention for improving sleep quality, strengthening psychological hardiness, and enhancing happiness among older women. Nevertheless, the results should be interpreted in light of several limitations. These included the purposive nature of participant selection, the absence of a follow-up assessment, and the exclusive inclusion of older women. Future studies should incorporate longer follow-up periods to determine the durability of the effects of yoga therapy on sleep quality, psychological hardiness, and happiness. Moreover, because the present study included only older women, similar research should be conducted among older men to improve the generalizability of the findings.
Ethical Consideration
Ethical Code
This article was derived from the first author's master's thesis in personality psychology at the Dezful Branch of Islamic Azad University.
Funding
This study received no financial support.
Authors’ Contributions
N. Sh.: Conceptualization, methodology, software, validation, formal analysis, investigation, visualization. L. M.: Conceptualization, methodology, software, validation, formal analysis, data curation, writing – original draft, writing – review & editing, supervision, visualization. D. R.: Conceptualization, methodology, software, validation, formal analysis, data curation, writing – original draft, writing – review & editing, supervision, visualization.
Conflict of Interest
 The authors declared no conflicts of interest.
Acknowledgments
The authors gratefully acknowledge all older adults who participated in this study.
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