Original Research

Measuring the effect of a yoga-based positive psychology intervention on positive and negative indicators of employee well-being in the higher education context

Leana Meiring, René van Eeden, Angelina Wilson Fadiji

Received: 04 Dec. 2025; Accepted: 22 May 2026; Published: 29 Aug. 2026

Copyright: © 2026. The Authors. Licensee: AOSIS.
This work is licensed under the Creative Commons Attribution 4.0 International (CC BY 4.0) license (https://creativecommons.org/licenses/by/4.0/).

Abstract

Orientation: A variety of factors have contributed to an increase in work stress among academic and administrative staff in higher education institutions in South Africa. This has a negative impact on the mental health and well-being of employees and thus on organisational performance.

Research purpose: This study measured the efficacy of a yoga-based positive psychology intervention (PPI) in improving well-being and reducing levels of perceived stress among a sample of employees in this context.

Motivation for the study: The literature showed that a multifaceted programme focussed on psychological strengths could provide an optimal long-term strategy for promoting employee well-being.

Research approach/design and method: Participants comprised 46 adults employed in an open-distance learning university who were invited to participate in a 36-week yoga-based PPI. The Mental Health Continuum Short Form, International Positive and Negative Affect Schedule Short Form, Utrecht Work Engagement Scale, and Perceived Stress Scale were used to measure positive and negative indicators of well-being. The measures were completed at four time points, and the Friedman and Wilcoxon signed-rank tests were used for the repeated measures analysis.

Main findings: The study’s findings showed improvement in overall mental health, emotional well-being and work vigour as well as reduced negative affect and perceived stress at the study’s conclusion. Other improvements in well-being were observed only at the mid-point of the study.

Practical/managerial implications: The success of a holistic workplace wellness programme that emphasises flourishing requires a long-term duration, and an on-site and in-person presentation. Employee commitment and organisational support are essential.

Contribution/value-add: The findings show that a yoga-based intervention can help promote emotional well-being, enhance energy levels and mental resilience at work, reduce perceived stress, and minimise negative emotions, thereby demonstrating a strategy for a successful wellness intervention.

Keywords: employee well-being; yoga; positive psychology intervention; affect; work engagement; stress; well-being scales; higher education institutions.

Introduction

Orientation

A positive psychology approach to mental health and well-being entails the intentional promotion of psychological strengths as opposed to treating symptoms of mental illness (Wissing, 2022). Within the positive psychology framework, well-being is defined in two spheres, which concerns feeling (hedonic) well and functioning (eudaimonic) well (Grant & McGhee, 2020), and it is most comprehensively studied by considering both positive and negative indicators (Donaldson et al., 2019). In line with this, Keyes (2002) conceptualises mental health as a multidimensional concept that encompasses emotional, psychological, and social functioning. A state of flourishing, which entails the presence of mental health and the absence of mental ill-health, has important implications in workplace contexts (Grant & McGhee, 2020; Spreitzer & Hwang, 2019). It links to positive organisational outcomes, such as greater productivity, work engagement and job satisfaction (Haddon, 2018; Moller & Rothmann, 2019).

The well-being of university employees in the South African context is concerning. Stress in higher education institutions (HEIs) is caused by a variety of factors, such as student protests, high workloads, time pressure, job insecurity, lack of role clarity and poor teamwork (Jasson et al., 2022; Poalses & Bezuidenhout, 2018). This has negative implications in terms of employee morale and organisational effectiveness, which calls for well-being intervention in this context (Mathews et al., 2022).

Research purpose and objectives

Advocates have pushed for more strengths-based approaches in workplace contexts (Marx, 2017; Stelzner & Schutte, 2016), yet a scoping review of positive psychology intervention (PPI) studies on the African continent indicated a paucity of workplace PPI studies in the South African context, particularly in HEIs (Guse, 2022). Promising results were found in a qualitative exploration of a yoga-based PPI aimed at promoting employee well-being at a selected South African HEI (Meiring et al., 2025). The present study was exploratory in nature. Quantitative data on the impact of the yoga-based PPI were obtained at various time points during and after the intervention. Validated well-being scales were used to assess positive and negative indicators of employee well-being. It was expected that participation in the PPI would improve mental health (H1), enhance work engagement (H2), and increase positive affect (H3). A decrease in negative affect (H4) and perceived stress (H5) was anticipated.

Literature review

Positive psychological interventions and employee well-being

Positive psychology interventions aim to promote well-being among non-clinical populations and are regarded as a strengths-based approach to wellness, aimed at enhancing positive feelings, cognitions, and behaviours (Hendriks et al., 2020; Lomas et al., 2015). With a focus on building strengths and promoting aspects related to well-being, workplace PPIs do not exclusively cater to distressed or troubled employees, which consequently removes the stigma of programme participation that is commonly associated with the involvement in reactive employee wellness initiatives (Dobson et al., 2019).

A meta-analysis by Donaldson et al. (2019) showed that workplace PPI is as effective for targeting aspects detrimental to well-being as it is for promoting desirable well-being indicators. Further supporting this, a 6-week in-person workplace programme including yoga, physical activity and mindfulness meditation significantly reduced perceived stress and negative affect at post-intervention and at 12-month follow-up, while increasing happiness and positive affect at post-intervention and through 12-month follow-up (De Bruin et al., 2020). A recent systematic review of mindfulness-based stress reduction and gratitude PPIs among healthcare workers demonstrated measurable improvement in positive indicators and reduction in negative indicators, including subjective well-being as well as stress and burnout from interventions ranging between 15 days and 6 months (Townsley et al., 2023). A randomised placebo-controlled field experiment investigating the effects of an online intervention for teachers showed that PPI can enhance aspects related to employee engagement (Dreer, 2020). In contrast, findings from Ouweneel et al. (2013) did not show a significant increase in work engagement following an 8-week online PPI. Meta-analytic findings from 22 studies by Donaldson et al. (2019) showed that workplace PPIs had a small-to-moderate effect on positive and negative well-being indicators. They noted that the delivery method (individual, group and online) played a role in terms of the impact on desirable and undesirable work outcomes.

Considering factors that could influence the effectiveness of workplace PPIs, Koydemir et al. (2020) suggest that face-to-face interventions may have a greater impact than interventions implemented using technology. De Bruin et al. (2020) underscore the value of offering programmes on-site to enhance adherence through regular attendance. In their model for sustainable happiness, Lyubomirsky et al. (2005) identify optimal timing, person-activity fit, variety of activity, sustained effort, and positive habits as key factors essential for successful well-being outcomes through intentional activity. Evidence also suggests that interventions of longer duration might have stronger effects, as they allow time to form new habits and incorporate them into everyday life (Khosla & Misra, 2022; Koydemir et al., 2020). Finally, using a multi-component PPI ensures that wellness is approached holistically and that both hedonic and eudaimonic aspects of well-being are targeted with a single intervention (Hendriks et al., 2020; Khosla & Misra, 2022). Feasibility studies in a real-world context must contend with methodological challenges such as self-selection, high attrition and small sample sizes (e.g. Osman et al., 2021). In the absence of a control group, the present study explored the effect of the well-being intervention in terms of multiple positive and negative outcome indicators measured repeatedly.

Yoga as a multi-component positive psychology intervention

Yoga is considered a physical, psychological, and spiritual science for the holistic growth of mind, body and soul (Bista & Bista, 2023). Lasting wellness promotion is at the heart of this ancient system, which entails numerous components that can be used to heal, integrate, balance and transcend suffering (Khosla & Misra, 2022; Siegel et al., 2016). Yoga teaches human beings the power to reveal their positive qualities and to reduce their deficiencies, similar to the focus of positive psychology (Akdeniz & Kaştan, 2023). In the classical text by Patanjali, yoga is systematised into eight limbs concerning social ethics, personal discipline, body postures, breathing practices, withdrawal of the senses, focussed concentration, meditation and personal transcendence (Bista & Bista, 2023; Saraswati, 2013a). The current study incorporated these core aspects in a single multi-component PPI with two programme components, theoretical and physical, thus going beyond previous work, which commonly focused on the physical aspects of yoga, breathing, relaxation and meditation (Della Valle et al., 2020; Puerto Valencia et al., 2019).

There is limited evidence of multi-component PPIs targeting healthy adults that combine mental, behavioural and physical components (De Bruin et al., 2020; Donaldson et al., 2019; Hendriks et al., 2020). The authors are not aware of any studies that utilised yoga as a multi-component workplace PPI, highlighting the unique contribution of this work. Although results are inconclusive due to limited statistical power, there is evidence that postural yoga can positively impact mental health (Domingues, 2018) and is effective for reducing stress in working adults (Della Valle et al., 2020). Yoga can benefit physical, emotional, psychological and social aspects of well-being (Akdeniz & Kaştan, 2023), qualifying it as a holistic approach to well-being.

Research design

Research approach

A quantitative approach informed the quasi-experimental, repeated measures, within-group design. This formed part of a larger mixed-methods study that explored the effectiveness and feasibility of a 36-week yoga-based PPI (Meiring, 2023).

Research method

Research participants

The study was conducted at an open-distance university in the Gauteng province of South Africa. Organisational support is essential for the successful implementation of a workplace intervention (Knight et al., 2017), and this was an important motivation for selecting the study setting. A purposive, non-random sampling strategy was used. Eligibility criteria included: (1) being employed in an academic or administrative position at any of the two target campuses of the selected HEI, (2) a willingness to commit to participation in all research activities, and (3) being physically capable of engaging in yoga practices of medium intensity.

The sample consisted of 46 eligible participants who volunteered to take part in the intervention (see Table 1). The majority of the sample was African (85%) and female (91%). Their age ranged from 24 years to 64 years. Most participants obtained a graduate/post-graduate degree (72%) or a post-matric qualification other than a degree (17%). Various job levels were represented. Employees were invited to form part of the intervention or a control group, but there was insufficient interest in the latter. Yoga studies frequently entail single-arm interventions without including a control group (Domingues, 2018), a potential limitation of programmes that require long-term commitment.

The Yoga-based positive psychology intervention

The intervention programme comprised theoretical and physical components presented over 36 weeks (see Appendix 1 Table 1-A1 and Appendix 1 Table 2-A1 for a detailed description of the intervention). The theoretical component consisted of 12 lessons dealing with yama and niyama observations. These life principles target social and psychological aspects of well-being, and participants were encouraged to apply them in their everyday lives. They received the lessons via email at regular intervals throughout the programme. The physical component consisted of two phases, namely the Pawanmuktasana series and Surya Namaskar (see Saraswati, 2013a and 2013b for details on the postures included in each series). Each phase was taught for 8 weeks to ensure gradual progression and familiarity through repetition. The phases were repeated before being combined in the final classes. Sessions started with a period of focused attention and mindfulness, followed by deep breathing, and concluded with a guided relaxation and meditation (Yoga Nidra). Four qualified and experienced yoga teachers presented the classes.

Measuring instruments

Demographic questionnaire

The questionnaire comprised questions on gender, age, race, relationship status, education, job title and job level.

Mental Health Continuum Short Form

The 14-item questionnaire measures emotional, psychological and social well-being on a six-point Likert scale ranging from ‘never’ to ‘every day’ (never = 0 and every day = 5) (Keyes, 2009; Lamers et al., 2011). Emotional well-being is measured by three items (happy, interested in life and satisfied), psychological well-being by six (self-acceptance, environmental mastery, positive relations with others, personal growth, autonomy, purpose in life), and social well-being by five (social contribution, social integration, social actualisation, social acceptance, social coherence). Overall scores as well as scores for each of the three subscales were used. The questionnaire has been validated in South Africa (Keyes et al., 2008; Schutte & Wissing, 2017), and Keyes et al. (2008) found acceptable internal consistency for the overall scale (α = 0.74). High internal consistency reliability was found for the overall scale for the baseline sample (α = 0.897).

International Positive and Negative Affect Schedule Short Form

The questionnaire comprises 10 items that measure positive affect (alert, inspired, determined, attentive, active) and negative affect (upset, hostile, ashamed, nervous, afraid) on a five-point Likert scale ranging from ‘never’ to ‘always’ (never = 1 and always = 5) (Thompson, 2007). Total scores are calculated for both subscales. High reliability values were found for both subscales in a South African study, 0.86 for positive affect and 0.83 for negative affect (Van Zyl & Rothmann, 2012), and acceptable values were found for positive (α = 0.734) and negative affect (α = 0.609) for the baseline sample in the present study.

Utrecht Work Engagement Scale

The nine-item version of the scale measures work engagement in terms of three core aspects (vigour, dedication, and absorption) on a seven-point Likert scale ranging from ‘never’ to ‘always’ (never = 0 and always = 6) (Schaufeli & Bakker, 2004). Subscales’ scoring is done by adding the scores in each subscale and then dividing the sum by the number of items in the subscale. The calculated subscale scores are added and divided by the number of subscales (three) to calculate the overall score. Local research on the factor structure provided inconclusive results. De Bruin and Henn (2013) recommend that the overall score be used whereas Gorgens-Ekermans and Herbert (2013) found support for a three-factor structure. Overall scores as well as scores for each of the three subscales were used in the present study. Geldenhuys et al. (2014) report acceptable reliability in the South African context, and high internal consistency reliability was found for the overall scale for the baseline sample in the present study (α = 0.952).

Perceived Stress Scale

The questionnaire comprises a positive subscale of four items and a negative subscale of six items, with responses on each ranging from ‘never’ to ‘very often’ (never = 0 and very often = 4) on a five-point Likert scale. Scores on the positive subscale are reversed before calculating an overall score. Scores are classified as low stress (0–13), moderate stress (14–26) and high stress (27–40). The Cronbach’s alpha value for the present study (0.758) corresponds to that found by Hamad et al. (2008) for a South African sample.

Research procedure and ethical considerations

Ethical clearance was obtained from the University of South Africa College of Human Sciences Research Ethics Committee (2018-CHS-0221). The institution that was approached to partake in the study provided written permission to conduct the study. All procedures were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.

Arrangements related to the recruitment of participants and the implementation of the programme were made with relevant role players. All employees were invited via an electronic advertisement to partake in the 36-week intervention. Information was provided on the research aim and related research activities, eligibility criteria, and participation expectations. The advertisement was re-published once weekly for 3 weeks, followed by a face-to-face information seminar. Participation was voluntary, and written informed consent was obtained from all individual participants involved in the study. Participants were also required to sign an indemnity form before participating in the physical yoga sessions. All information was kept confidential.

The yoga-based PPI was implemented over 36 weeks, and data were gathered at four different time intervals, namely 0 weeks (baseline), 18 weeks (intervention mid-point), 36 weeks (intervention conclusion), and 48 weeks (12 weeks post-intervention). An online questionnaire was completed by the participants at each point. The questionnaire included a demographic section and measures of mental health and well-being, work engagement, positive and negative affect and perceived stress.

Statistical analysis

Participants received a link to complete the electronic questionnaire at four time points (0 weeks, 18 weeks, 36 weeks and 48 weeks), and responses were recorded in a password-protected Excel spreadsheet. During data preparation, mean imputation was used to deal with item non-responses found in the four measures (Durrant, 2005; Rässler & Riphahn, 2006). This implies that missing values for a variable are replaced with the mean of observed values for the same variable, thereby maintaining the sample size in instances of item non-response. Microsoft Excel (Microsoft Corp., Redmond, WA, US) and Statistical Package for the Social Sciences (SPSS) version 27 software (IBM Corp., Armonk, NY, US) were used to analyse the data. Descriptive statistics were calculated for the scale and subscale scores. Cronbach’s coefficient alpha was used to determine the internal consistency reliability of the questionnaires. The normality assumption was tested for the Mental Health Continuum Short Form (MHC-SF), the International Positive and Negative Affect Schedule Short Form (I-PANAS-SF), the Utrecht Work Engagement Scale (UWES-9) and the Perceived Stress Scale (PPS-10) using the Shapiro-Wilk test, skewness and kurtosis values, histograms, scatter plots and Q-Q plots. Based on the results, non-parametric inferential statistics, namely the Friedman and Wilcoxon signed-rank tests, were used for the repeated measures analysis. These tests are rank-based and thus less sensitive to outliers and are suitable for data that violate stringent parametric assumptions (Field, 2009).

The Friedman test was suitable to determine differences in indicators between time points for participants who provided data at all relevant times (Field, 2009; Wassermann et al., 2019). It accounts for the statistical error incurred when drawing multiple comparisons. Time 1 and Time 3 (n = 18) were compared to determine changes from the start to the end of the intervention, while Time 1 and Time 4 (n = 12) were compared to determine whether there were lasting effects. Pairwise comparisons with the Dunn-Bonferroni post hoc test were used to further explore significant findings. Significance values were adjusted by the Bonferroni correction for multiple tests. Kendall’s coefficient of concordance (Marshall & Marquier, n.d.) was used to determine the effect sizes, and these were interpreted in terms of Cohen’s guidelines (0.10 = small; 0.30 = medium; 0.50 = large; Field, 2009).

The Wilcoxon signed-rank test was used to further explore the impact of the intervention at each time point (T1 × T2: n = 28; T2 × T3: n = 18; T1 × T3: n = 19; T3 × T4: n = 12). Separately testing the alternative pairs resulted in slightly larger sample sizes; however, running multiple tests of individual pairs also increases the likelihood of a Type I error. The effect size was calculated by dividing the z value by the square root of the number of observations across the two time points. Cohen’s criteria were used to interpret the values. A significance level of 0.05 was used in the study. Two-tailed significance was considered to provide for potential fluctuation in the direction of change between the different time points.

Results

Descriptive statistics

The descriptive statistics for the scale and subscale scores at each data collection point are presented in Table 2. There were outliers in most cases, and the median was regarded as a more accurate measure of central tendency (Field, 2009). Visual inspection of the data showed an increase in the case of the positive indicators from Time 1 to Time 3, and followed by a slight decrease or a plateau from Time 3 to Time 4. In the case of the negative indicators, there was a decrease from Time 1 to Time 4.

Pre-post intervention changes

Participation in the programme led to significant improvements on emotional well-being, χ² (2, n = 18) = 7.033, p < 0.05 and the vigour component of work engagement χ² (2, n = 18) = 9.781, p < 0.05 when comparing the baseline results with results at the conclusion of the intervention (see Table 3). The Dunn-Bonferroni post hoc tests (Table 4) indicate significant increases between Time 1 and 3 in both cases. The effect size was small in the case of emotional well-being (Kendall’s W = 0.195) and moderate in the case of vigour (Kendall’s W = 0.272).

Negative affect χ² (2, n = 18) = 7.651, p < 0.05 and perceived stress χ² (2, n = 18) = 12.030, p < 0.05 decreased significantly from start to end of the intervention. Post hoc testing showed a significant change between Time 1 and Time 3 for negative affect, and between Time 1 and Time 3 and between Time 2 and Time 3 for perceived stress. The effect size was small in the case of negative affect (Kendall’s W = 0.213) and moderate in the case of perceived stress (Kendall’s W = 0.334).

Post-intervention effects

Time 1 (baseline) and Time 4 (12 weeks post-intervention) were compared to determine whether there were lasting effects. No significant difference was found for any of the scales or subscales (see Table 5).

Comparison of individual time pairs

The impact of the intervention was further explored by considering changes in the scale and subscale scores between the different points of data collection using the Wilcoxon Signed-Ranked Test. The results are reported in Table 6.

Mental health

There was a significant increase in overall mental health from Time 1 to Time 2 (z = 2.50, p < 0.05; T1, Md = 46.00; T2, Md = 52.42) and from Time 1 to Time 3 (z = 2.11, p < 0.05; T1, Md = 46.00; T3, Md = 55.00), and a significant decrease from Time 3 to 4 (z = −2.10, p < 0.05; T3, Md = 55.00; T4, Md = 52.00). In terms of effect size, these changes were moderate (T1–T2, r = 0.33; T1–T3, r = 0.34; and T3–T4, r = −0.34).

A similar pattern was found for the emotional well-being subscale with an increase from the start of the intervention to the mid-way point (z = 2.92, p < 0.05; T1, Md = 11.00; T2, Md = 12.00), from the mid-way point to the end of the intervention (z = 2.44, p < 0.05; T2, Md = 12.00; T3, Md = 13.00), and from the start of the intervention to the end (z = 2.85, p < 0.05; T1, Md = 11.00; T3, Md = 13.00). A significant decrease was found from the end of the intervention to 3 months post-intervention (z = −2.16, p < 0.05; T3, Md = 13.00; T4, Md = 12.00). The effect sizes were moderate (T1–T2, r = 0.39; T2–T3, r = 0.41; T1–T3, r = 0.46; T3–T4, r = −0.44).

Psychological well-being (z = 2.00, p < 0.05; T1, Md = 22.00; T2, Md = 24.25) and social well-being (z = 1.98, p < 0.05; T1, Md = 15.00; T2, Md = 17.00) increased significantly from Time 1 to Time 2. The effect sizes were small (r = 0.26) and moderate (r = 0.31), respectively.

Work engagement

A significant increase was found for the overall work engagement scale between Time 1 and Time 2 (z = 2.34, p < 0.05; T1, Md = 4.33; T2, Md = 4.75) with a moderate effect (r = 0.31). Similar results were found for the vigour construct of work engagement (z = 2.91, p < 0.05; T1, Md = 3.91; T2, Md = 4.33; r = 0.39).

Positive and negative affect

Positive affect increased significantly between Time 1 and Time 2 (z = 2.45, p < 0.05; T1, Md = 17.50; T2, Md = 20.00) with a moderate effect (r = 0.33). A significant decrease was found for negative affect from the start of the intervention to the midway point (z = −2.90, p < 0.05; T1, Md = 10.00; T2, Md = 9.00) and from the start of the intervention to the end (z = −2.49, p < 0.05; T1, Md = 10.00; T3, Md = 8.00). The effect sizes were moderate (T1–T2, r = −0.39, T1–T3, r = −0.40).

Perceived stress

A similar pattern was found for the second negative indicator, perceived stress, with a significant moderate decrease between Time 1 and Time 2 (z = −2.66, p < 0.05; T1, Md = 19.00; T2, Md = 16.00; r = −0.36) and Time 1 and 3 (z = −2.75, p < 0.05; T1, Md = 19.00; T3, Md = 16.00; r = −0.45).

Discussion

Outline of the results

The aim of the study was to explore the effectiveness of a yoga-based PPI to promote well-being among employees at a selected South African HEI. It was expected that participation in the PPI would improve mental health (H1), enhance work engagement (H2) and increase positive affect (H3). A decrease in negative affect (H4) and perceived stress (H5) was also anticipated.

Mental health

The findings offered partial support for the first hypothesis. There was a significant increase in overall mental health, as well as in the emotional, psychological, and social well-being constructs from the start of the intervention to the mid-point at 18 weeks (small to moderate effect). Overall mental health and emotional well-being also improved from the start of the programme to its conclusion after 36 weeks (a moderate effect). There were, however, no lasting effects, with a significant decrease seen in overall mental health and emotional well-being from the conclusion of the programme to 12 weeks post-intervention. The effect sizes were moderate.

These findings correspond with previous research investigating the effects of yoga-based interventions on employee well-being indicators for 6 weeks (De Bruin et al., 2020) and 16 weeks (Harris et al., 2015; Maddux et al., 2017), respectively. Further support from previous studies shows that psychological (Bista & Bista, 2023), as well as individual and relational, well-being can be enhanced through regular physical yoga practice and by incorporating the yamas and niyamas observances in everyday life (Ivtzan & Papantoniou, 2014; Sharma & Rawat, 2023). Contrary to these findings, Strijk et al. (2013) found no significant effects of a 6-month wellness intervention, including a yoga group, on well-being indicators among university employees. However, in a secondary analysis, they showed that high compliance with the yoga sessions was necessary for significant effects.

High programme adherence and participant commitment over the first 18 weeks of the programme in the current study could explain the improvements in mental health observed during the initial phase of the intervention (18 weeks). Adherence to both the physical and theoretical components was highest during this period. Continued participation over the 36 weeks enhanced emotional-well being and overall mental health. Trent et al. (2019) found sustained long-term increases at a 2-month follow-up in well-being among educational professionals following a 3-day weekend yoga-based wellness retreat. In a similar vein, De Bruin et al. (2020) also reported lasting long-term effects on well-being indicators up to 12-months following a 6-week intervention. The present study, however, showed no lasting effects post-intervention, with a significant decrease observed at 12 weeks following the end of the programme.

Work engagement

Partial support was found for the second hypothesis. Vigour and overall work engagement increased significantly from the start of the intervention to the 18-week mid-point (moderate effect). There was also a significant increase in the vigour subscale from the start to the end of the programme at 36 weeks (a moderate effect).

These findings align with a study including a seven-session online yoga course that involved awareness activities, discourses, and guided meditations presented over 48 days. Chang (2021) reports significant increases from pre- to post-programme scores in overall work engagement and the vigour and dedication subscales. Trent et al. (2019) also found significant improvements for overall work engagement and the vitality subscale at post-intervention and 2-month follow-up following a 3-day off-site yoga-based wellness programme. Participants’ continued long-term use and practice of the programme tools following the retreat were noted as a possible explanation for the findings. Our findings are in line with a number of other studies that investigated the effects of well-being interventions on work engagement (Keeman et al., 2017; Ouweneel et al., 2013; Strijk et al., 2013) and found intervention effects only on overall work engagement and the vitality subscale. Alper and Başaran (2023) found no significant differences between pre- and post-test work engagement scores following a 12-week face-to-face yoga intervention.

Work engagement, conceptualised as vigour, absorption and dedication, is associated with employee well-being and can be compromised by stress and poor mental health (Kumar et al., 2020). The initial improvements in mental health during the first 18 weeks of the programme could, in part, account for the increase observed in work engagement (Kumar et al., 2020). The design of the study, however, did not allow for the exploration of causality. Chang (2021) furthermore identified energy as a key contributor to work engagement. In line with other studies (De Longis et al., 2020; Kobylińska et al., 2018; Menezes et al., 2015), the present results indicate that the yoga-based PPI may serve as a viable lunchtime refresher activity to help combat work fatigue and subsequently boost the degree of vigour with which employees engage in their work (Knight et al., 2017).

Positive and negative affect

The findings did not provide conclusive support for the third hypothesis. Positive affect only increased during the initial phase of the programme at 18 weeks (moderate effect), but no significance was found at the programme’s conclusion at 36 weeks. The results, however, supported the fourth hypothesis. Negative affect decreased significantly from the start of the programme to the mid-point at 18 weeks (moderate effect), and from the start of the intervention to the end (moderate effect).

The present results are supported by findings from Bista and Bista (2023) and De Bruin et al. (2020), but contrast with those of Harris et al. (2015). They did not find significant post-intervention effects on negative affect after 16 weeks, but did find significant increases in positive affect.

Positive affect and emotional well-being are related (Keyes, 2002; Lambert et al., 2015), and the absence of significant increases in positive affect at 36 weeks was unexpected given the increase in emotional well-being at the intervention’s conclusion. This could be explained by the hedonic treadmill effect, returning to baseline happiness levels once the novelty of a new venture wore off (Khosla & Misra, 2022; Pohlmeyer, 2017; Sheldon et al., 2013).

Perceived stress

In support of the fifth hypothesis, significant decreases (moderate effect) in perceived stress were found from the start of the programme to the midway point at 18 weeks and to the programme conclusion at 36 weeks. This was not maintained at the 12-week post-intervention follow-up.

The reduction of perceived stress is one of the most commonly reported findings of yoga interventions among a wide range of populations (Ciezar-Andersen et al., 2021; Della Valle et al., 2020; Puerto Valencia et al., 2019). Similar to the present study, Maddux et al. (2017) found significant decreases in perceived stress among university employees participating in a yoga intervention at 8 and 16 weeks. Contradictory findings are reported by Harris et al. (2015), who found no significant decreases in perceived stress from educators participating in a 16-week yoga and mindfulness intervention. The study by De Bruin et al. (2020) found lasting positive effects on stress up to 1 year following a 6-week intervention. However, the present study results did not show lasting effects at the 12-week post-intervention measure.

The current results suggest that participating in this lunchtime yoga-based PPI can serve as a personal resource that enables employees to manage their stress effectively, albeit in the short-term. Some argue that yoga enhances well-being and reduces stress by downregulating the sympathetic nervous system and hypothalamic-pituitary-adrenal axis (Bista & Bista, 2023). The observed enhancement in the emotional well-being dimension in the present study suggests that this occurred through a more positive appraisal of stressors and emotional regulation. Although the study by Harris et al. (2015) found that participation in a yoga intervention improved distress tolerance, it did not enhance emotional regulation. The increased mindful awareness that can be cultivated through a yoga practice could also be responsible for experiencing reduced stress (Chang, 2021; Magalhaes Das Neves et al., 2014). Moreover, mental health serves as a protective resource against stress (Lamers et al., 2015; Trompetter et al., 2017), and the positive impact the programme had on the mental health indicator could be a possible reason for the reduction found in perceived stress.

Practical implications

The holistic nature of the yoga-based PPI, incorporating both physical practice sessions along with the yama and niyama observances within a single multi-component workplace wellness programme is a unique contribution of the present study. Moreover, the structure and presentation of the 36-week PPI adhered to requirements identified in existing literature as important aspects for programme success, such as long-term duration and on-site and in-person presentation (De Bruin et al., 2020; Khosla & Misra, 2022; Koydemir et al., 2020). The study thus illustrates some of the aspects that need to be considered when planning an optimal long-term strategy to promote employee well-being. It also contributes on a methodological level. Using a repeated-measures design added depth to the analysis of the programme effects on selected well-being indicators, revealing nuances of change over time. The theoretically supported changes in the well-being indicators also reflect positively on the validity of the measurement scales used in this study. Finally, in line with Strijk et al. (2013), this study highlights the importance of high programme adherence as an essential aspect for a positive impact. This would not be possible without organisational support for the intervention programme.

Limitations and recommendations

Particular research limitations should be noted when interpreting the reported results. The current study was quasi-experimental in nature, and the possible influence of factors other than programme participation cannot be ruled out (Barns, 2019; Gravetter & Forzano, 2009). However, qualitative reports from participants confirmed that taking part in the programme and using the programme tools enhanced their sense of well-being (Meiring et al., 2025).

Despite on-site access to the intervention, the attrition from week 18 to week 36 and from week 36 to week 48 was substantial. The sample size was consequently small. This compromised the statistical power of the analysis and may have contributed to the non-significant results for some variables (Barns, 2019; Field, 2009). High attrition and small sample sizes are common limitations reported for workplace intervention studies (Keeman et al., 2017; Ouweneel et al., 2013; Strijk et al., 2013) and, specifically, PPIs (Bolier et al., 2013). The decline in programme adherence after the 18-week mid-point could also have led to non-significant results, as commitment has been highlighted as critical for positive impact (Strijk et al., 2013). Bolier et al. (2013) nevertheless:

[E]ncourage researchers to publish in peer-reviewed journals, even when the sample sizes are small or when there is a null finding of no effect, as this is likely to reduce the publication bias in positive psychology. (p. 17)

Moreover, these results cannot be generalised as the non-random sample is not representative of the larger population. It is worth noting that the self-selected sample of interested employees who volunteered for the programme is more reflective of a real-world scenario in which employees voluntarily enrol themselves into workplace wellness programmes. Self-selection also helped ensure person-activity-fit, an important factor for wellness promotion through intentional activity (Khosla & Misra, 2022; Lyubomirsky et al., 2005). Replication of this study in other settings is needed to further determine the programme’s impact on selected outcome variables.

Conclusion

The present study showed that the yoga-based PPI can help promote emotional well-being, enhance energy levels and mental resilience at work, reduce perceived stress, and minimise negative emotions among participating employees. The study results suggest that programme adherence is an important factor in achieving a successful impact on employees’ well-being and that long-term continuation of the programme is required for sustained effects. Utilising a variety of yoga-based tools to deliver a multi-component PPI in the South African higher education context as a holistic proactive workplace wellness approach makes a unique contribution to the existing body of knowledge. Methodological considerations when evaluating a multi-component, in-person PPI of longer duration were highlighted, and the study contributes to evidence for the reliability and validity of the well-being scales as measures of positive and negative indicators of well-being.

Acknowledgements

This article includes content that overlaps with research originally conducted as part of Leana Meiring’s Doctoral thesis titled ‘Workplace wellness: Yoga as a positive psychology intervention for employees in a South African higher education institution’, submitted towards the degree of Doctor of Psychology in the Department of Psychology, University of South Africa, South Africa in 2023. The thesis was supervised by René van Eeden and Angelina Wilson Fadiji. Portions of the data, analysis, and discussion have been revised, updated and adapted for publication in a journal. The original thesis is publicly available at: https://ir.unisa.ac.za/handle/10500/30633. The authors affirm that this article complies with ethical standards for secondary publication, and that appropriate acknowledgement has been given to the original work.

This article is based on data from a larger study. A related article focusing on a qualitative exploration of the feasibility of the yoga-based PPI has been published in SA Journal of Industrial Psychology, 51(0), a2249 (https://doi.org/10.4102/sajip.v51i0.2249). The present article addresses a distinct research question, focusing on the impact of the yoga-based PPI on positive and negative indicators of well-being using a repeated-measures design.

Competing interests

The authors reported that they received funding from the Master’s and Doctoral Bursary of the University of South Africa, which may be affected by the research reported in the enclosed publication. The authors have fully disclosed those interests and have implemented an approved plan for managing any potential conflicts arising from their involvement. The terms of these funding arrangements have been reviewed and approved by the affiliated University in accordance with its policy on objectivity in research.

CRediT authorship contribution

Leana Meiring: Conceptualisation, Data curation, Formal analysis, Investigation, Methodology, Resources, Writing – original draft, Writing – review & editing. René van Eeden: Resources, Supervision, Writing – original draft, Writing – review & editing. Angelina Wilson Fadiji: Resources, Supervision, Writing – original draft, Writing – review & editing. All authors reviewed the article, contributed to the discussion of results, approved the final version for submission and publication, and take responsibility for the integrity of its findings.

Funding information

The research was supported by the Master’s and Doctoral Bursary of the University of South Africa.

Data availability

The data that support the findings of this study are available upon reasonable request from the corresponding author, René van Eeden. The data are not publicly available because they contain information that could compromise participant anonymity and confidentiality.

Disclaimer

The views and opinions expressed in this article are those of the authors and are the product of professional research. They do not necessarily reflect the official policy or position of any affiliated institution, funder, agency or publisher. The authors are responsible for this article’s results, findings, and content.

References

Appendix 1