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   Table of Contents     
ORIGINAL ARTICLE  
Year : 2016  |  Volume : 9  |  Issue : 1  |  Page : 20-26
Improvements in well-being and vagal tone following a yogic breathing-based life skills workshop in young adults: Two open-trial pilot studies


1 Department of Psychology, University of Arizona, Tucson, AZ, GA, USA
2 Department of Psychiatry, University of North Carolina at Chapel Hill, Chapel Hill, NC, GA, USA
3 International Association for Human Values, Washington, DC; Nova Southeastern University Lifelong Learning Institute, Davie, FL, GA, USA
4 RTI International, Research Triangle Park, NC, GA, USA
5 RTI International, Atlanta, GA, USA
6 Center for Compassion and Altruism Research and Education, School of Medicine, Stanford University, Stanford, CA, GA, USA
7 Department of Human Development and Family Studies, Penn State University, State College, PA, USA

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Date of Web Publication14-Dec-2015
 

   Abstract 


Background: While efficacy of Sudarshan Kriya Yoga (SKY) has been demonstrated in a number of prior studies, little is known about the effects of SKY taught as part of the Your Enlightened Side (YES+) workshop designed for college students and other young adults.
Aims: This study aimed to assess the effects of YES+, a yogic breathing-based life skills workshop, on multiple measures of well-being and physiological stress response.
Materials and Methods: Two nonrandomized open-trial pilot studies were conducted with a total of 74 young adults (age 25.4 ± 6.6 years; 55% female). Study 1 collected a variety of self-report questionnaires at baseline, postworkshop, and 1-month follow-up. Study 2 collected self-report questionnaires in addition to electrocardiography with a stationary cycling challenge at baseline and 1-month follow-up.
Results: Study 1: Improvements in self-reported depression (P's ≤ 0.010), perceived stress (P's ≤ 0.002), life satisfaction (P's ≤ 0.002), social connectedness (P's ≤ 0.004), and gratitude (P's ≤ 0.090) were observed at postworkshop and 1-month after workshop relative to baseline. Study 2: Improvements in self-reported emotion regulation were observed at 1-month follow-up relative to baseline (P = 0.019). Positive and Negative Affect Schedule-Expanded Form positive affect increased (P = 0.021), while fatigue and sadness decreased (P's ≤ 0.005). During the stationary cycling challenge, rate to recovery of electrocardiography inter-beat interval also increased from baseline to 1-month follow-up (P = 0.077).
Conclusions: These findings suggest that a life skills workshop integrating yogic breathing techniques may provide self-empowering tools for enhancing well-being in young adults. Future research is indicated to further explore these effects, particularly in regards to vagal tone and other aspects of stress physiology.

Keywords: Emotion regulation; meditation; stress management; vagal tone; well-being; yoga breathing techniques.

How to cite this article:
Goldstein MR, Lewis GF, Newman R, Brown JM, Bobashev G, Kilpatrick L, Seppälä EM, Fishbein DH, Meleth S. Improvements in well-being and vagal tone following a yogic breathing-based life skills workshop in young adults: Two open-trial pilot studies. Int J Yoga 2016;9:20-6

How to cite this URL:
Goldstein MR, Lewis GF, Newman R, Brown JM, Bobashev G, Kilpatrick L, Seppälä EM, Fishbein DH, Meleth S. Improvements in well-being and vagal tone following a yogic breathing-based life skills workshop in young adults: Two open-trial pilot studies. Int J Yoga [serial online] 2016 [cited 2019 Jun 26];9:20-6. Available from: http://www.ijoy.org.in/text.asp?2016/9/1/20/171718



   Introduction Top


The transition from adolescence to adulthood, particularly for college students, is accompanied by several major life changes and challenges. For many individuals, this is a period when one moves away from home, begins interacting with different peer groups, and has greater financial and academic responsibilities. The emotional stress associated with these changes is correlated with less time devoted to sleep,[1] increased alcohol intake,[2] reduced academic performance,[2],[3] and increased rates of anxiety disorders and/or depression.[4]

Your Enlightened Side (plus more) (YES+) is a life skills workshop with a strong emphasis on breathing practices for reducing stress and increasing well-being. Additional stress management tools including meditation, yoga, and interpersonal exercises that impart social and emotional learning skills and stress reduction strategies complement the breathing techniques.

The central practice taught in YES+ is a unique rhythmical breathing technique called Sudarshan Kriya.[5] It is taught along with two preparatory breathing practices: An advanced form of Ujjayi breathing (breathing against airway resistance) and bhastrika (forceful nasal breathing). Collectively, these three breathing practices are referred to as Sudarshan Kriya Yoga (SKY).

Prior literature has demonstrated significant improvements in psychological and physiological outcomes of SKY in adults, including decreases in subjective stress,[6] clinical and subclinical depression and anxiety,[6],[7],[8] posttraumatic stress symptoms,[9],[10],[11] impulsivity,[12] and tobacco use,[13] as well as increases in calm, mental focus,[14] emotion regulation,[15],[16] and overall well-being.[6],[17]

However, little is known about the effects of SKY specifically taught in the YES+ workshop format designed for college students. One randomized controlled trial has demonstrated and attenuated levels of subjective stress and several hematological markers, including lymphocytes and platelet count, during exam periods following SKY training.[18] These findings have not yet been replicated, and the extent to which the effects of YES+ generalize to other health-related changes such as cardiovascular function remain unclear.

To address this gap in the literature and provide further preliminary data on the specific effects of YES+ on well-being, two separate nonrandomized open-trial studies were conducted. Study 1 implemented a collection of measures targeted at a variety of domains of subjective well-being. Study 2 sought to further explore changes in self-reported affect and emotion regulation scales, as well as changes in autonomic function, with a physical exercise task.


   Study 1 Materials and Methods Top


Procedure and participants

Fifty undergraduate and graduate students at the University of Wisconsin–Madison were recruited [Table 1]. Participants provided written informed consent and underwent a brief screening interview. Participants with a reported history of panic or bipolar disorder were excluded due to the potential adverse effects of the SKY technique for these individuals. Ethics approval was obtained from the IRB at the University of Wisconsin–Madison.
Table 1: Demographic information

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Data collection for the first wave of enrollment included 2 times points: Within 1 week prior to the workshop (T1) and within 1 week following the 5-day YES+ workshop (T2). For the second enrollment wave, a 3rd time point was added 1-month postworkshop (T3) to assess longer-term outcomes. For each time point, participants were sent a link to access the questionnaires via secure online database.

Your Enlightened Side+ workshop

The workshop totaled 20 h across 5 consecutive days and was taught by certified instructors with at least 250 h of prior training. From day three onward, participants were instructed to begin practicing a daily 20–25 min home SKY practice and were encouraged to attend once-weekly 90-min postworkshop sessions for a longer version of SKY in a group format.

Self-report measures

Outcome measures included the 10-item Center for Epidemiologic Studies Depression Scale (CESD-10),[19] a version of the Perceived Stress Scale (PSS)[20] that asked about the last week instead of the last month, the Social Connectedness Scale,[21] SWLS,[22] and 6-item Gratitude Questionnaire.[23]

Statistical analysis

Internal reliability for each scale was assessed via Cronbach alpha. For the first wave of participants with 2 times points, paired two-tailed t-test was conducted to evaluate mean change from T1 to T2. For the second subgroup with 3 times points, repeated measures ANOVA was utilized to test the effect of time for each measure, with post-hoc tests (Bonferroni-corrected) assessing specific changes relative to baseline for any measure with a significant omnibus effect (α = 0.05). Finally, differential change between the two subgroups for the overlapping T1 and T2 data was evaluated via two-way mixed model ANOVA. Analyses were conducted in SPSS (IBM Corp., Armonk, NY).


   Study 1 Results Top


For the first recruitment wave, data at 2 times points were available for all 12 participants [Figure 1]. For the second wave (n = 38), which contained 3 times points, 5 participants were lost to follow-up postworkshop (T2). Sixteen participants were unable to complete questionnaires at the 1-month follow-up (T3), primarily due to summer vacation scheduling conflicts. Thus, the data from all 3 times points were analyzed for 17 participants, with an additional 28 participants for T1 and T2 only.
Figure 1: Study 1 enrollment and data collection flow

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Results from the self-report measures are displayed in [Table 2]. All scales demonstrated moderate to high internal reliability (α = 0.76–0.95). For the subgroup with only T1 and T2 data, a significant improvement was observed for the measurements of depression (CESD-10), PSS, social connectedness, and SWLS. The Gratitude Questionnaire exhibited a trend-level difference (P = 0.053). For participants with all 3 times points, a significant effect of time was observed for all measures. Significant improvements were observed on all measures from baseline to T2 and were sustained through 1-month postworkshop (T3) with the exception of the Gratitude Questionnaire (P = 0.090 following Bonferroni correction).
Table 2: Study 1 self-report measures

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A subgroup ("T1-T2 only" subgroup and "T1-T3" subgroup) x time (T1 and T2) mixed model ANOVA indicated no significant interaction effects across the self-report measures (P = 0.140–0.840), suggesting that those only completing the first 2 times points reported the similar changes from T1 to T2 as those completing all 3 times points.


   Study 2 Materials and Methods Top


Procedure and participants

Twenty-nine young adults were recruited from the greater Atlanta area [Table 1]. Ethics approval was obtained from the IRB at Research Triangle Institute, and all participants provided written informed consent. Inclusion and exclusion criteria were the same as for Study 1.

Similar to Study 1, the data were collected in two waves. The first workshop was held after recruiting 14 participants. The second workshop was held 1 month later for an additional 15 participants. The same YES+ workshop design, timeline, and daily home practice instructions as Study 1 were used. Experimental visits for Study 2 occurred at baseline and at a 4-week follow-up.

Self-report measures

Participants completed the emotion dysregulation measure (EDM),[24] a 13-item Likert scale containing two subscales ("Emotional Sensitivity/Emotional Response" and "Return to Emotional Baseline"), and the Positive and Negative Affect Schedule-Expanded Form (PANAS-X).[25]

Cycling challenge and heart rate variability measures

As part of this pilot study, a physical exercise task was also implemented for a subset of participants with electrocardiogram (ECG) recordings at each time point. Participants were positioned on a stationary bicycle, allowed approximately 5 min rest, then engaged in a self-paced cycling challenge lasting approximately 5 min, followed by a 5–10 min recovery period. ECG signals were collected using previously published standard procedures.[26] Due to technical issues during recordings; baseline and 4-week follow-up data were only available for 11 participants.

To assess cardiac vagal tone, the rate to recovery from the cycling challenge was the primary construct of interest. As illustrated in [Figure 2], for each recording, a polynomial function was fitted to the inter-beat interval (IBI) data derived via EZ-IBI software (UFI, Morro Bay, CA). Then, the local peak preceding the recovery slope and the peak immediately following this transition were identified, along with the inflexion point between these peaks. To capture the recovery rate not confounded by individual differences in the prominence of the second peak caused by asymptotes of some fitted lines (resulting in the peak occurring in the middle of the recovery period rather than the beginning), the linear point-slope was calculated at the inflexion point. Additional, commonly used metrics of heart rate (HR) variability were computed based on the IBI series data using CMetX.[27]
Figure 2: Inter-beat interval across rest, stationary bicycle effort, and recovery periods for a representative participant from Study 2 at preworkshop and 4-week follow-up time points. A least-squares polynomial of best fit was calculated for each recording. Within each effort to recovery transition window (dotted lines), the local minimum (a) and maximum (b) were determined, between which the inflexion point (c) was used to derive maximal linear point-slope of the curve as a measure of recovery rate. Across participants with available data at both time points (n = 11), mean point-slope increased from preworkshop to 4-week follow-up (P = 0.077)

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Statistical analysis

As with Study 1, internal reliability for each self-report scale was assessed using Cronbach alpha, and differences in self-report and IBI measures between the 2 times points (baseline and 4-week follow-up) were evaluated using paired t-test. Relationships among these measures were assessed with linear regression. Analyzes were conducted in SAS (SAS Institute Inc., Cary, NC) and MATLAB (MathWorks, Natick, MA).


   Study 2 Results Top


Three participants dropped out due to job-related relocations, one due to difficulties with childcare and one withdrew after baseline measurements before the intervention began.

Both self-report composite scales and subscales demonstrated moderate to high internal reliability (α = 0.78–0.96). From baseline to 4-week follow-up, the EDM instrument measuring the overall changes in emotional dysregulation decreased (P = 0.019), driven by changes in both the Emotional Sensitivity/Emotional Response subscale (P = 0.016) and the Return to Emotional Baseline subscale (P = 0.045). For the PANAS-X, composite positive affect increased (P = 0.021) [Table 3], along with seven associated sub-scales including joviality (P = 0.031), self-assurance (P = 0.008), attentiveness (P = 0.011), and serenity (P = 0.001). A significant difference was not observed for composite negative affect, although subscales for sadness (P = 0.005) and fatigue (P < 0.001) decreased significantly, and hostility (P = 0.057) evidenced a trend-level change.
Table 3: PANAS-X scale scores at baseline and 4 weeks following workshop in study 2 (n=29)

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Commonly used measures of cardiac chronotropy including HR, mean IBI, root mean square of successive differences, and logarithm of respiratory sinus arrhythmia corresponding to rest, effort, and recovery periods of the cycling challenge are presented in [Table 4]. Using a difference metric as done in prior research [28] to assess the change in average values from effort to recovery periods of the cycling challenge, no significant changes on these four metrics were observed between baseline and week 4 (0.143 < P < 0.481).
Table 4: Measures of cardiac chronotropy during cycling challenge in study 2 (n=11)

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However, the linear point-slope of the IBI recovery curve, a measure that more precisely reflects the rate to recovery process, demonstrated a trend-level effect indicating an increase in the recovery rate from baseline (mean change in IBI/s = 3.03 ± 1.15) to 4-week follow-up (4.06 ± 1.74), T (10) = 1.97, P = 0.077 [Figure 2]. This change corresponded to a 48% mean increase in the IBI recovery rate. No difference was observed for the goodness-of-fit of the polynomial functions fitted to the IBI data (R2 = 0.80 ± 0.12 vs. 0.82 ± 0.12), P = 0.540. The self-report composite scales and sub-scales did not significantly correlate with IBI point-slope at either time point or proportionally to the amount of change.


   Discussion Top


The results of these two open-trial pilot studies suggest that the YES+ workshop is associated with improvements in both subjective well-being and autonomic system functioning. These changes including reductions in depression, perceived stress, sadness, and fatigue, and improvements in social connectedness, satisfaction with life, gratitude, emotion regulation, and positive affect including joviality, serenity, self-assurance, and attentiveness from baseline to 1-month following completion of the workshop.

Strength of Study 2 was the inclusion of a physical exercise task to evaluate the changes in autonomic regulation reflected in the rate to recovery of HR. The increase in IBI slope of recovery from the cycling challenge may reflect enhanced parasympathetic activity and vagal tone afforded by SKY and other components of the YES+ workshop.[5] Mean values and variability in IBI across rest and effort periods observed here corroborate prior literature.[28],[29],[30] It is notable that the recovery slope of the cycling challenge increased from baseline to several weeks following YES+, as the workshop does not explicitly target physical fitness. This observation would benefit from replication and additional data to explore the extent of changes in vagal tone. While this analysis focused on IBI as a simple, intuitive measure with high reliability relative to other HR variability measures,[31] it is important for future studies to explore additional metrics controlling for respiratory rate in the context of both physical and psychological stress tasks.[32]

Limitations

Because of the uncontrolled nature of both study designs, placebo effects are not accounted for and may have influenced results. The self-report measures and voluntary completion of the questionnaires in Study 1 created the potential for self-attribution and self-selection biases. However, the follow-up analyses indicated that differential change across participants was unlikely, and the physiological measures of Study 2 corroborate the self-report data of changes hypothesized to reflect improvements in well-being. Randomized controlled trials combining self-report psychological and objective physiological measures with larger sample sizes would allow for enhanced evaluation of the relationships between these outcomes and the YES+ interventions.


   Conclusions Top


These two nonrandomized trials of YES+ suggest that this workshop holds potential as a self-empowering, nonpharmacological method for enhancing stress management and wellness in college students. Given the long-term impact of stress on physical and emotional health, providing such a workshop to young adults might help to prevent several consequences correlated with poor stress management, ranging from substance use and risky sexual behaviors to eating disorders, and cardiovascular disease. The known association between positive affect and healthy life choices further increase the potential benefits of YES+.

Acknowledgments

The authors are grateful for the voluntary commitment from participants in both studies; Spencer Dawson, Ezra Smith, Samantha Reznik, and other colleagues for the insightful discussions; Dr. John Allen for direct and indirect support with discussions and resources for data analysis; Diedre Jackson, Josette Agarwal, Annelies Richmond, and Daniel Moss of the Art of Living Foundation for providing the workshop instruction; and the Art of Living Center in Atlanta for providing the space for workshops and other resources in kind support.

Financial support and sponsorship

This research was funded in part by RTI International's Independent Research and Development funds (to SM) and National Science Foundation Graduate Research Fellowship (to MRG).

Conflicts of interest

M.R. Goldstein, G.F. Lewis, J.M. Brown, G. Bobashev, L. Kilpatrick, D.H. Fishbein, and S. Meleth declare no conflicts of interest. E.M. Seppälä was the workshop instructor for Study 1. R. Newman supervised YES+ instructors in Study 2 and is Director of Research and Health Promotion for the Art of Living Foundation, North America.

 
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Correspondence Address:
Sreelatha Meleth
BioStatistics and Epidemiology Unit, Environmental Health Sciences Division, RTI International 2951 Flowers Road South, Atlanta, GA 30341
USA
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/0973-6131.171718

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