Yoga is a complex mind–body approach (Iyengar, 1991), even though the majority of people in Western cultures considers it merely a physical activity (MacDonald, 2013; Sarbacker, 2014). Many experts claim that practicing yoga is a cost-effective way to improve mental health and quality of life (Büssing et al., 2012a; Shroff et al., 2017; Domingues, 2018; Csala et al., 2021).

Empirical findings largely support this view. For example, a number of intervention studies support the idea that yoga practice has a favorable impact on perceived stress after 8–16 weeks of practice (Smith et al., 2007; Gard et al., 2012; Bilderbeck et al., 2013; Schmalzl et al., 2018). For the most part, yoga interventions utilize a specific yoga tradition called hatha yoga. Classical hatha yoga is a practical discipline that includes, among others, the practice of physical postures (‘asanas’) and breath control (‘pranayama’) in order to facilitate meditation and attain spiritual goals (‘samadhi’; based on the Hatha Yoga Pradipika, an influential yogic text composed by Svatmarama in the 1400s; Mallinson, 2011). In Bilderbeck et al.’s (2013) study, in contrast with a passive control group, perceived stress and psychological distress decreased significantly after 10 weeks of practicing hatha yoga in a prison population. Gard et al. (2012) evaluated the outcome of a four-month-long residential program with Kripalu yoga (a branch of hatha yoga that emphasizes compassion and consciousness that allow the practitioner to observe events without judgement, a capacity much like mindfulness). It was found that participation predicted reduced stress and enhanced quality of life, and thus contributed to the well-being of young adults. In the study of Schmalzl et al. (2018), 8 weeks of yoga-based practices (YBP) focusing on movement and breath decreased perceived stress in young beginners. Based on the findings of Smith et al. (2007), hatha yoga is as effective in reducing stress as relaxation after ten weekly one-hour-long class. Moreover, when comparing advanced hatha yoga practitioners with beginners, the former reported considerably lower levels of stress (Brisbon and Lowery, 2011). Beyond perceived (self-reported) stress, a beneficial physiological effect, i.e., reduction of salivary cortisol, was also found (West et al., 2004; Schmalzl et al., 2018). According to the reviews of Ross and Thomas (2010) as well as Pascoe and Bauer (2015), yoga may cause these desirable effects by soothing the nervous system, i.e., by down-regulation of the hypothalamic–pituitary–adrenal axis and the sympathetic nervous system. Yoga might be beneficial in this regard for vulnerable populations as well, such as elderly people or people suffering from mental disorders characterized by excessive amounts of stress (Bonura and Pargman, 2009; Doria et al., 2015; Jindani et al., 2015).

Concerning positive affectivity like joyfulness or alertness, and negative affectivity that refers to unpleasurable feelings (Watson, 1988), yoga might also have a beneficial effect (Meissner et al., 2016). Although a recent review of Domingues (2018) found contradictory results with respect to affectivity, some evidence supports the idea that increasing the amount of time spent with yoga practice leads to increase of positive affectivity and decrease of negative affectivity (Meissner et al., 2016).

Although an enhanced satisfaction with life due to yoga practice could also be expected, empirical results have not been conclusive so far. Participants reported marginally increased satisfaction with their life in three yoga-based intervention studies (Impett et al., 2006; Elavsky and McAuley, 2007; Mathad et al., 2017). In another study, although quality of life, as assessed with the Satisfaction with Life Scale (SWLS; Diener et al., 1985), improved for epilepsy patients practicing yoga, this effect was not shown with the short version of the World Health Organization Quality of Life (WHOQOL-BREF; Harper et al., 1998; Lundgren et al., 2008).

Spirituality (religious or non-religious) refers to a pursuit of meaning in life and connection to transcendental phenomena, and involves specific values and beliefs related to this transcendental view of life (Sessanna et al., 2007). MacDonald (2013) highlighted the importance of including spirituality in yoga research, as its benefits for mental health appear evident. Yoga practice increased self-rated spirituality in a few studies (Büssing et al., 2012b; Gaiswinkler and Unterrainer, 2016). Likewise, 5 days were enough to elicit increased spiritual growth in the study of Braun et al. (2012) in a residential, Kripalu yoga-based program. Based on the systematic review of Csala et al. (2021), both quantitative and qualitative studies suggest that yoga, especially regular practice, positively affects several aspects of spirituality. It is also worth mentioning that yoga practitioners exhibited the highest level of spirituality when compared to practitioners of martial arts of Eastern origin (aikido, judo) and controls (Western sports; Szabolcs et al., 2021). However, there are also a few studies with conflicting results about whether yoga increases spirituality, and if so, how. Two similar, hatha yoga-based interventions designed for cancer patients, yoga did not increase spirituality. In Cramer et al.’s (2016) 10-week-long yoga program for patients with colorectal cancer, no significant group differences emerged with respect to spiritual well-being; on the other hand, although practicing yoga for 12 weeks did not increase spirituality in breast cancer patients, its initial level was more preserved compared to waiting list controls, based on Moadel et al.’s (2007) work. In both cases, however, adherence was compromised; moreover, drop-out rate was also high in Cramer et al.’s (2016) program. In Csala et al.’s (2020) study, university students, who participated in a 10-week-long beginner hatha yoga program, generally reported higher levels of spiritual connection, regardless of whether they received verbal cues referring to spirituality or physical performance from their instructor. According to the authors’ explanation, yoga might exert its effect primarily through bodily processes and not through verbal instructions.

It is often claimed that yoga can also affect body awareness, i.e., the perceived ability to detect bodily changes and to focus on them. Enhancement of various aspects of body awareness or interoceptive awareness is considered a common mechanism of action for mind–body therapies (Mehling, 2016). In a cross-sectional study Daubenmier (2005) found higher body awareness in healthy adult women practicing yoga compared to aerobic exercisers and to those who did neither. Rani and Rao (1994) found that a 3-month hatha yoga program (daily 1 h practicing) increased body awareness among healthy adults. Delaney and Anthis (2010) also found in a cross-sectional study that mind–body emphasis could be associated with higher body awareness. In two cross-sectional studies, Tihanyi and colleagues examined advanced yoga practitioners. These participants showed significantly higher levels of body awareness compared to people who do other sports (kung-fu, aerobics, ballroom dance; 2016a); additionally, weekly frequency of yoga practice among advanced practitioners correlated positively and significantly with body awareness, and the latter also proved to be a mediator between yoga practice and well-being (2016b). Similarly, in Impett et al.’s (2006) study, the more participants practiced yoga, the more they were likely to report an increase in their body awareness (although the effect was only marginal in this case). However, no changes in body awareness were reported by Csala et al. (2020) after a 10 week long (1.5 h per week) yoga course.

Overall, practicing yoga has been associated with improvement in several psychological factors that potentially positively impact an individual’s quality of life to a considerable extent. However, current literature is not without conflicting results, especially regarding how yoga influences affectivity, the level of general satisfaction with life and spirituality. In some cases, the inconclusive nature of the question at hand may derive from the use of different measurements instruments (as in case of the Satisfaction with Life Scale vs. WHOQOL), population properties (as in case of the cancer patients who may face extreme existential crises that hinders them from experiencing spiritual well-being), or the lack of sufficient evidence [as mentioned in the review of Domingues (2018) examining yoga and positive mental health indicators]. Despite the negative results, the overwhelming majority of studies do support the notion that yoga is beneficial to body and mind, so positive outcomes can reasonably be expected. Nevertheless, current literature would still benefit from more information on these subjects from healthy populations.

A new feature of this study, compared to others available in the literature, is that it incorporates other psychoeducational elements rather than just yoga, making it more easily acceptable by a community sample. An important contribution is that very few studies have examined the effects of yoga interventions on body awareness or spirituality and rather used shorter interventions. Finally, in the present study the yoga intervention is well defined compared to the previous ones available in the literature (Csala et al., 2021).

The aim of the present study was to investigate the impact of a complex 3-month yoga-based intervention on participants’ perceived stress, affectivity, satisfaction with life, spirituality and body awareness. Based on the empirical findings, the following hypotheses were formulated and tested: Yoga practice can decrease negative mental states such as (i) perceived stress and (ii) negative affectivity. Additionally, yoga leads to (iii) increased positive affectivity and (iv) higher satisfaction with life. Also, we expected an increase in (v) spirituality and (vi) body awareness.

In a controlled intervention study, a complex hatha yoga intervention with a duration of 3 months led to an increase in spirituality, in the perceived tendency to notice body changes (MAIA noticing), the ability to direct attention to them (MAIA attention regulation), using them as means of self-regulation (MAIA self-regulation), and considering them a reliable and important indicator of the internal state (MAIA trusting and body listening), and a decrease in negative affect and perceived stress. However, no impact on positive affect, satisfaction with life, and some of the variables measured by the MAIA questionnaire such as Emotional Awareness, and the ability to distract attention from unpleasant body sensations (Not distracting) and their affective concomitants (Not worrying) were found.

Both perceived stress and negative affect decreased during the yoga intervention. The former outcome is in line with findings reported in the literature (West et al., 2004; Smith et al., 2007; Bonura and Pargman, 2009; Brisbon and Lowery, 2011; Gard et al., 2012; Bilderbeck et al., 2013; Doria et al., 2015; Jindani et al., 2015; Schmalzl et al., 2018), and further supports the notion that yoga can be an effective intervention for the management of stress. Concerning the finding about reduced negative affectivity, our results may contribute to the dissolution of contradictions implied by the review of Domingues (2018) and viewing yoga as a tool for soothing negative affective states.

Our finding about enhanced spirituality due to yoga practice also fits nicely into existing literature (Braun et al., 2012; Büssing et al., 2012b; Gaiswinkler and Unterrainer, 2016; Csala et al., 2021; Szabolcs et al., 2021). As the majority of studies with healthy populations, and now ours too, support the notion that enhanced spirituality and yoga are associated, it is likely that the two intervention studies that did not yield similar results (Moadel et al., 2007; Cramer et al., 2016) reached different conclusions because of the properties of a special population.

However, contrary to our preliminary assumptions, we could not report consistent results about the relationship between yoga practice and various aspects of interoceptive awareness. Yoga positively affected the ability to notice, attend to, listen to, and place trust in relevant body sensations, and even regulate one’s state (e.g., reduce tension, reach a state of calmness) based on them. Meanwhile, yoga did not seem to lead to more insight into emotional experience related to body sensations, nor did it lead to less worrying about and less distracting oneself from unpleasant body sensations. The lack of relationship between these aspects of body awareness and yoga is intriguing. Similarly, to our results, Bornemann et al. (2015) did not find significant changes in the aforementioned aspects; they reason that training bodily focus leads to better attention and clarity about bodily sensations and affective states, but enhanced bodily focus in itself is not sufficient for further processing the unpleasant sensations, cognitions or emotions that may arise. In Floyd et al.’s (2022) study, ten sessions of yoga practice did not elicit improvements in the Not-Distracting and Not-Worrying subscales of MAIA either. It is possible that the reported associations (Daubenmier, 2005; Delaney and Anthis, 2010; Tihanyi et al., 2016a,b) were valid only cross-sectionally, e.g., as a consequence of self-selection. The questionnaire we used captured more dimensions of the broad construct of interoceptive awareness, thus there was more room for differential results than in case of studies that used questionnaires (typically the BAQ) with a single composite score (Rani and Rao, 1994; Daubenmier, 2005; Impett et al., 2006; Tihanyi et al., 2016b). It may not even be reasonable to draw a parallel between the aforementioned instruments, as Vig et al. (2022) recently found that correlations between the BAQ and the MAIA scales Not Worrying and Not Distracting are virtually non-existent, as well as only weak to moderate associations have been found with the remaining six subscales. Consequently, the authors suggest that these instruments cannot be used interchangeably, as they presumably do not measure the same underlying construct. It is also worth noting that the subscales Not Worrying and Not Distracting were only weakly related to a general factor of interoception in a study that aimed to examine the originally proposed factor structure of the MAIA (Ferentzi et al., 2020). Based on these findings, we could conclude that regular yoga practice does not improve the ability to regulate body-related distress. However, an improvement was found for five scales out of six that belong to the general interoception factor.

Interestingly, positive affectivity and satisfaction with life were not impacted by the yoga intervention. Contrary to the findings supporting the existence of a positive association between yoga and positive affectivity (Impett et al., 2006; Kiecolt-Glaser et al., 2010; Tihanyi et al., 2016a), West et al. (2004) also found no increase in positive affectivity after yoga practice. In their study, positive affect increased in people practicing African dance, but did not change in the yoga group, while negative affect decreased in both conditions. Also, salivary cortisol increased in the dance group, and decreased in the yoga group. West et al. (2004) drew the conclusion that although both activities are beneficial for the psyche, the underlying physiological processes differ considerably. It is also possible, that other aspects, such as forms or frequency of practice are of key importance. Meissner et al. (2016) found that when practitioners who originally took a Western approach to yoga practiced more traditionally (every day in the morning) for 2 weeks, their positive affectivity did actually increase. Tihanyi et al.’s (2016a) findings point to this direction too, as in their study weekly frequency of yoga practice was associated with higher levels of positive affect. These results and ours pose more questions about how yoga and positive affectivity really relate to each other.

As far as life satisfaction is concerned, one possible explanation is that domain-general life satisfaction is more stable over this time interval—there is a high year-to-year correlation, and major life changes and relatively stable intra-and interpersonal resources are more likely to account for the variance, exerting their dominating effect throughout years (Ehrhardt et al., 2000).

In summary, the yoga intervention reported in this study had a positive impact on many aspects of healthy psychological functioning, such as perceived stress, negative affectivity, spirituality, and various indicators of self-reported interoception. These findings, that support the idea that regular yoga practice can be beneficial for mental health (Büssing et al., 2012a; Shroff et al., 2017; Domingues, 2018), are certainly worthy of further scientific investigation.

These results can contribute to improving the well-being of the participants, and the participating teachers can also contribute to the healthy lifestyles of their students by passing on the knowledge acquired. Changes in the lifestyle and psychological well-being of these students of the participating teachers may also be worth investigating in the future.

It is important to note that participation in the intervention took place in three waves and there was no corresponding control group in the first wave. The practical yoga classes were held separately for schoolteachers and civilian workers. Subjects were mainly women and high level of motivation and interest of participants clearly limits the generalizability of the findings. The intervention as a whole was studied and compared to an inactive group; therefore, the contribution of certain components (e.g., physical activity, education, social factors) cannot be assessed. Weekly frequency of home practice was self-reported. The use of different yoga traditions poses a methodological problem in our study, which often occurs in yoga research, because the distinction between these traditions is not clearly defined nor well documented (Elwy et al., 2014; Park et al., 2014, 2018; Sullivan et al., 2018; Csala et al., 2021). However, all of these traditions can be traced back to, and are fundamentally related to hatha yoga. Additionally, because of the passive control condition participants were not blind regarding their grouping thus the expectations of the experimental participants could have an impact on the results in particular because we used self-report measures. In case of measured constructs, spirituality is not a well-defined concept and there is no one universally accepted definition or measurement method for it. Finally, the low internal consistency of the MAIA not distracting scale (both at pre- and post-intervention) renders the respective findings difficult to interpret.

In summary, a complex 3-month-long yoga-based intervention was able to decrease negative affect and perceived stress, increase spirituality and many aspects of interoceptive awareness.

The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.

The studies involving human participants were reviewed and approved by Research Ethics Committee of the Faculty of Education and Psychology at ELTE Eötvös Loránd University. The patients/participants provided their written informed consent to participate in this study.

FK contributed substantially to the conception, design, interpretation of data, and provided feedback in order to improve the manuscript. AK, EN, FK, and BC prepared the manuscript. FK and AK conducted the statistical analyses. CSe and ÁB set up and implemented the intervention. JK, VG, CSu, and SB substantially contributed to the data collection. All authors contributed to the article and approved the submitted version.

This research was supported by the Hungarian National Scientific Research Fund [K124132, K137724].

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

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