The number of single mothers in Korea surveyed by the National Statistical Office in 2019 was 20,761, and it is expected to be higher with consideration for single mothers not included in the survey. In Korean society, single mothers are often bullied or excluded from the original family because they are still perceived as ‘obstructive’ or ‘violating social norms’. This negatively affects the mental health of single mothers. Due to economic difficulties and reduced social support, single mothers have mental health problems such as chronic stress, depression, and anxiety (Rousou et al., 2019), and it has been reported that they are more vulnerable to mental health disorders such as depression than married mothers (Kim et al., 2018). It is presumed that these results are due to the fear of social criticism as a single mother or abandonment by the family.

The number of single mothers raising children has shown a recent increase in Korea. They wanted to live in hiding, fearing damage to their children caused by themselves (Kim et al., 2012). Findings from another study showed that mental health had a greater effect on children from single-parent families compared with ordinary children (Crosier et al., 2007). Based on these results we can predict that the emotions of unstable and depressed single mothers can be directly linked to negative attitudes toward parenting. However, the focus of studies on single mothers has been on social support for resolving economic difficulties; these studies mainly discussed the degree of depression, anxiety, and stress according to the social relationship and economic level of single mothers (Kim et al., 2018; Rousou et al., 2019). However, few studies conducted to improve the mental health of single mothers through exercise have been reported. Therefore, it is necessary to provide emotional support along with economic support since the mental health of single mothers is very important not only for themselves but also for parenting.

In neurological terms, depressive disorder is associated with symptoms caused by decreased control of the vagus nerve (Henje Blom et al., 2014). A direct relationship between depressive symptoms and vagus nerve activity was suggested by Agelink et al. (2002). The degree of vagus nerve tension, which is associated with depression, affects the process of top-down and bottom-up emotional processing (Park et al., 2013), and this process has been reported to be essential for the relationship between emotions, communion, and vagus nerve balance (Farb et al., 2015). In this way, the brain and body can be helpful in mental and physical therapy through control of changes in the autonomic nervous system and emotions and behavior (Taylor et al., 2010), and mental and physical therapy has a positive effect on body perception, including conscious self-acceptance (Farb et al., 2015; Mehling et al., 2011). Accordingly, yoga has been proposed as an effective method for mental and physical therapy by Gard et al. (2014).

Yoga, which originated in ancient India, is a training method that fosters harmonization of the body, emotions, and thoughts, including relaxation, physical posture (Asana), breathing control techniques (Pranayama), and meditation (Dhyana). In particular, Hatha-yoga, which is well-known to the public, provides training in yoga movements that prepare the body for self-realization, that is, Asana. Physiologically, yoga stimulates the parasympathetic nervous system to aid in the function of the autonomic nervous system, thus it is used for prevention and treatment of disease (Stephens, 2017). As a result, yoga was recently recognized as a field of alternative medicine, and its complementary effect on mental and physical therapy has been identified (Prathikanti et al., 2017; Sullivan et al., 2018).

In addition, yoga has been reported to be effective in reducing negative emotions such as aggression, depression, and anxiety by promoting a sense of physical and mental calm, as well as improvement of self-regulation (Klainin-Yobas et al., 2015; Miller et al., 1995; Prathikanti et al., 2017). The practice of yoga focuses on the inner senses for improvement of emotional awareness, and caring for one’s inner experiences increases resilience by enhancing self-pity and empathy for others (Gilbert, 2014). Resilience is the ability to avoid stress and return to the original state (Smith et al., 2010). In a recent study resilience was found to promote spontaneous brain activity against subjective well-being in adults (Kong et al., 2018). People with a high level of resilience are not swayed by their situation, are emotionally stable, and view the future with optimism. Although some people are naturally born with this resilience, it can also be acquired. Among the methods of physical movement for enhancement of resilience, the resilience enhancing effect of yoga training has been demonstrated in a number of studies (Dale et al., 2009; Gard et al., 2014; Trent et al., 2019).

In particular, yoga training is not only important for overcoming negative perceptions of single mothers and living independently, it can also be expected to have a positive effect on raising children. Therefore, the purpose of this study was to examine the effectiveness of yoga training in reducing depression and improving resilience for single mothers raising children.

A corresponding sample t-test was performed for comparison of the difference in scores for depression and resilience before and after participation in the yoga training program. As a result, statistically significant differences were observed with regard to depression (t=4.352, P<0.01) and resilience (t = −4.031, P<0.01) of the participating group, which were significant with regard to emotional control (t = −2.915, P<0.05), impulse control (t = −3.956, P<0.01), cause analysis (t = −2.158, P<0.05), life satisfaction (t = −1.77, P<0.05), and thankful (t = −2.440, P<0.05) factors. However, the average score (M=22.9) for the self-optimism factors of the program participating group was higher than before the program participation (M=21.7), but without statistical significance. On the other hand, in the control group, no statistically significant difference was observed with regard to depression, overall resilience, and subfactors.

The Wilcoxon test was performed in order to confirm the results of the paired t-test by assuming nonnormal distribution due to small sample size. Significance probabilities are shown in Table 3. The results of the Wilcoxon test were comparable to those of the parametric paired t-test.

This study was conducted in order to confirm the effectiveness of the yoga training program in reducing depression and improving resilience of single mothers. The discussion based on the research results is as follows.

First, based on the finding that respiratory exercise activates the aesthetic nerve and helps regulate the autonomic nervous system. this study provided training in yoga breathing with the aim of reducing depression in unmarried mothers (Henje Blom et al., 2014). Depressed people usually bend their heads, so that the spine is curled forward, and breathing is not smooth due to the tilt of the chest. Tweeddale et al. (1994) reported that regular breathing causes changes in metabolism and is effective for improvement of psychological symptoms such as depression. Based on the report by Taylor et al. (2010) and Muehsam et al. (2017), breathing and exercise affect the musculoskeletal system, cardiovascular system, and immune function, and also promote positive change in emotional well-being. These results support the findings of this study, which confirmed the effect of reducing depression through chest-opening movements and breathing training that aids breathing. Single mothers in the participating group were able to focus on breathing naturally through repetition of chest-opening movements, and as the session passed, the time they had to focus on themselves increased. In fact, for single mothers in the participating group the depression score measured after nine sessions of breathing training had changed to the normal range (M=12.9), which proved its effectiveness in lowering depression through breathing.

Second, the single mothers in the participating group did not perform the Asana movement properly at first, however, with repeated performance they gradually got used to it. It is thought that through this process of focusing only on Asana movement training, the ability of unmarried mothers to control themselves improved. The results of yoga training for enhancement of self-efficacy and self-esteem of healthy adults were investigated by Deshpande et al. (2009). Trent et al. (2019), who applied 2-month yoga and meditation programs to educational and social service professionals, reported a positive effect on adaptive resilience and psychological and professional well-being. It can be assumed that in this study yoga training had a positive effect on the ability for self-awareness and self-regulation of single mothers.

Third, positive emotions are known to be effective in resolving negative emotions such as depression and promoting resilience and psychological well-being (Taylor et al., 2017). The power of positive feelings, such as gratitude, passion, and hope are closely related to life satisfaction and well-being (Seligman et al., 2005), and happiness reduces negative emotions and maximizes positive emotions through a pleasant past, present pleasure, optimistic and hopeful future (Duckworth et al., 2005). Changing the internal resources of humans in a short period of time is difficult. However, positive expression and practice of one’s thoughts against irrational and negative thinking is helpful in achieving positive change of internal resources (Taylor and Conger, 2017). In this study, selection of the topic of meditation was based on the sub-area of resilience, and after meditation, single mothers had time to express their minds.

To date, attempts to investigate improvement of the quality of life through social interest and economic support for single mothers have continued. However, few studies have focused on mental health by recognition of the inner strengths of single mothers through exercise therapy. Follow-up studies should be conducted for application of mental health programs that can be helpful in achievement of positive change in the thoughts and emotions of single mothers and their effectiveness should be investigated.

Finally, this study has several limitations. First, there is a limitation in generalizing the results because only 20 single mothers participated as subjects. In addition, yoga training programs may not be the only factor influencing psychological improvement. For example, the emotional support of the group during yoga training may have an effect on the psychological state.