Abstract
Objective
The primary aim of this study was to examine differences in yoga practice between persons with and without chronic pain. Secondarily, we describe use of the Essential Properties of Yoga Questionnaire, Short Form (EPYQ-SF) for self-report.
Design
Participants were members of an existing cohort of veterans who completed a 2015-2016 survey focused on pain and nonpharmacological health practices. Cohort members who reported yoga in the past year (n=174 [9.4%] of 1850) were eligible for the present study, which used multiple-contact mixed-mode survey methodology to collect data on yoga practices. The EPYQ-SF was used to assess properties and context of yoga practice. Practice patterns were compared for participants with and without chronic pain. To explore potential reasons for reported yoga practice patterns, focused semi-structured interviews were conducted with a subset of participants.
Results
Of 174 participants contacted, 141 (82%) returned the yoga questionnaire and 110 (78% of respondents) were still practicing yoga. Among yoga practitioners, 41 (37%) had chronic pain. Practitioners with chronic pain reported gentler (2.8 vs 3.1, 5-point scale) and less active (2.9 versus 3.3) yoga practice than those without. Those with chronic pain attended yoga studios less frequently and reported shorter yoga practices than those without. Most yoga practice was self-directed and at home.
Conclusions
Differences in yoga practice of persons with and without chronic pain have implications for implementation of yoga interventions for chronic pain. Future interventions should focus on alternative individual delivery formats or addressing barriers to group practice among people with chronic pain.
Keywords: Yoga, Chronic Pain, Veterans, Mixed Methods, Qualitative Interview
Introduction
Although yoga is rooted in the Vedic traditions of India,1 contemporary practices are multi-modal, integrating distinct techniques including relaxation, meditation, stretching, and aerobic exercise.2 The many yoga styles and lineages3 make it challenging for researchers to capture the experiences and motivations of the estimated 14% of U.S. adults4 who practice yoga (i.e., yoga practitioners).
Yoga is increasingly studied as a treatment for musculoskeletal pain and recommended as a treatment for common conditions such as chronic low back pain.5-8 Yoga practitioners have worse pain and more medical problems than the general US population, suggesting that pain management may be a motivation for yoga practice.9,10 However, more people report using yoga for maintaining general health and improving well-being rather than for managing pain specifically.10-12 Given the increasing focus on yoga as a pain management intervention, additional evidence is needed about how people with and without chronic pain practice yoga.
The main objective of this study was to compare characteristics of yoga practice of persons with and without chronic pain. We used surveys to collect data on yoga practice in an existing cohort of US National Guard veterans and in-depth interviews with a subset of participants to gain insight into the findings.13 Secondarily, we aimed to describe implementation of a new short-form self-report tool for describing characteristics of yoga practice, the Essential Properties of Yoga Questionnaire (EPYQ).14
Methods
Participants and procedures
Participants were recruited from an existing cohort study, Readiness and Resilience in National Guard Soldiers (RINGS),15 which has been ongoing since 2006. RINGS cohort members are veterans of or still connected with the Minnesota Army National Guard and deployed to Iraq, Afghanistan or Kuwait during 2006 to 2011. Follow up surveys have been conducted in several waves since their return from deployment. Studies that use the RINGS data have been published that study predictors of post-traumatic stress disorder (PTSD) symptom severity, depression and alcohol abuse, personality factors associated with health outcomes and others. The most recent RINGS mailed survey (fielded October 2015–September 2016), focused on chronic pain and use of complementary and nonpharmacological health practices.16 Of 3,890 cohort members initially eligible, 1,850 participated in the 2015/2016 survey (response rate 48.2%). The responders were similar to the overall demographics of the cohort, which has been previously reported.16 Eligibility for the present yoga study was based on response to a single-item dichotomous question about use of yoga in the past year on the 2015/2016 survey. Respondents who reported practicing yoga in the past year (n=174 [9.4%] of 1850) were eligible. Study procedures were approved by Minneapolis Veterans Affairs (VA) Healthcare System and University of Minnesota institutional review boards.
Data collection
Multiple-contact mixed-mode survey methodology was used to collect follow-up information about yoga practice from October to December 2016.17 Packages including a questionnaire, cover letter, and $20 gift card incentive were mailed to 174 eligible RINGS participants. At 2-week intervals, one postcard reminder and one additional survey mailing were sent to non-responders. Non-responders to the three mailings were contacted by phone up to three times and given the option of completing the full questionnaire by phone or receiving a third copy in the mail.
Measures
Demographics.
Participants were asked to report updated information on educational attainment, relationship status and National Guard status.
Pain.
Pain over the prior 7 days was measured using the 3-item Pain severity, interference with Enjoyment of life, and interference with General activity (PEG) scale.18 A difference of about 2 points on the PEG scale is considered meaningful.19 The National Pain Strategy population health pain persistence item (5-response version) was used to define chronic pain as pain on at least half the days in the previous 6 months.20 This single item measure of pain chronicity has been demonstrated to be valid for use in surveys and as a global measure across multiple anatomical sites.20
Self-reported health.
Overall health was assessed using the single-item global heath and 1-year prior health questions from the Veterans RAND 12 Item Health Survey.21,22 Overall health was dichotomized as excellent/very good or good/fair/poor.
Yoga.
To assess regularity of practice, participants were asked how many years in their entire life they had practiced yoga and how often they practiced in the past month (never, once, a few times, a few times a week, daily or almost daily). Participants were also asked how many months out of the past 12 they practiced yoga even once and, during those months, how often they practiced on average. Participants who did not practice yoga in the previous year were told to skip the remainder of the questions.
To characterize participants’ yoga practice, we used a new self-report version of the Essential Properties of Yoga Questionnaire, Short Form (EPYQ-SF) (see Figure, Supplemental Digital Content 2, a reproduction of the yoga survey form). The EPYQ was developed to quantify components of yoga interventions along multiple dimensions, for use with research studies.23 The EPYQ has 2 parts, which describe properties and context of yoga practice. The section on properties of yoga has 62 items which assess various features of yoga practice (e.g., , holding poses or meditation). These 62 properties were found to form 14 subscales through factor analysis.
The EPYQ-SF was created by eliminating factors that were the least statistically robust. In addition, expert opinion of the EPYQ authors and other yoga researchers influenced elimination or retention of some factors that were near recommended cutoffs. The investigators evaluated intraclass correlation coefficients, test-retest correlations, mean ratings across 15 different styles of yoga, and standard deviations of the mean. Of the 14 original EPYQ dimensions, 7 dimensions were eliminated through this process (Acceptance/Compassion, Restorative Postures, Bandhas, Body Awareness, Health Benefits, Social Aspects and Yoga Philosophy). The 7 dimensions that were retained are Breathwork, Physicality, Active Postures, Meditation/mindfulness, Mental and Emotional Awareness, Spirituality, and Individual Attention.
Further, the language of the original instrument was adapted to be administered directly to the yoga participants, instead of to researchers. For example, in the short form participants were asked, “how much did your yoga practice or instruction include…” whereas the original language asked, “how much did the instructor mention or include…” For each properties item, respondents are asked, “Over the past 6 months, how much did your yoga practice or instruction include…” with response options of not at all, a little bit, moderate amount, quite a lot, very large amount, and don’t know. The items were treated as ordinal and scored 1 to 5, with 5 being very large amount. Context is assessed with 20 items assessing past-year location, instruction, duration, and individual or group practice. For each context item, respondents are asked about frequency with options of never, rarely, sometimes, often, or very often. For this analysis, responses were dichotomized as regular use (sometimes/often/very often) or not regular use (never/rarely).
Data analysis
Cronbach’s alpha (α) for internal consistency of the EPYQ properties of yoga practice section was 0.90, which is typically considered to be excellent. The internal consistency of the seven subscales ranged from 0.63 for the individual attention subscale to 0.90 for the mental & emotional awareness subscale. The standard error of measurement was calculated with the subscale standard deviation and Cronbach’s α, SD×(1−α)½.
Characteristics of respondents with and without chronic pain were compared by calculating differences and 95% confidence intervals. Mean scores were calculated for each of the 7 EPYQ yoga practice properties subscales. Subscale means were compared by T-test with unequal variances, with 20% power and a 5% type I error rate. Data were analyzed using Stata version 15.24
Qualitative interviews
Concurrent with yoga survey administration, a subset of participants was invited to participate in-depth semi-structured qualitative interviews. Respondents were eligible for qualitative interviews if they reported clinically significant pain (defined as grade II-IV on the Graded Chronic Pain Scale version 2.0) on the most recent RINGS survey25 and reported having, “attended a yoga class or did yoga on your own or with others” in the previous month on the yoga follow-up survey.
A purposive, heterogeneous sampling approach was used to obtain diverse interview participants with respect to gender and level of pain interference. Participants were recruited until about 12 interviews were scheduled, with a plan to continue recruitment if saturation had not been reached by that point in qualitative analysis. Four experienced qualitative interviewers (MD, SKF, CE, EA) conducted interviews in a private room or by telephone using a semi-structured guide that started with general questions about pain and pain management, then shifted to focused questions about yoga (see Table, Supplemental Digital Content 1, which shows the interview guide). Interviews were recorded and transcribed verbatim by a professional transcription agency. Qualitative interview participants were compensated $130. Of the 12 scheduled interviews, 11 were completed and 1 cancelled. We determined thematic saturation had been reached, so we did not recruit any additional interviewees.
Qualitative analysis
Transcripts were reviewed for errors and de-identified. The qualitative analysis followed completion of the quantitative analysis to allow exploration of major findings of the quantitative phase.13 Analysis was guided by a semi-inductive approach. We analyzed participants’ responses to the interview questions while considering unanticipated themes and topics that emerged during analysis. The analysis of the yoga transcripts proceeded in two cycles.26 First, all transcripts were read by the first author [MTD] in their entirety. The first author developed an initial code list by re-reading the transcripts and assigning descriptive conceptual phrases to salient elements. The list of conceptual phrases was then condensed and categorized into simple descriptive codes that highlight the similarities and differences between transcript elements. The first author then analyzed the list of descriptive codes to identify initial thematic elements that were developed through the interviews. The full analysis team, including the 4 interviewers (MTD, SKF, CE, EA) and principal investigators of the parent study (EEK & MAP), discussed the thematic findings identified in the initial coding during analysis meetings. In the second cycle, the first author refined the initial list of thematic findings into major themes relevant to the questions raised in the quantitative phase27 by grouping similar codes from the first cycle into a smaller number of categories. A content-analytic summary table was then constructed from the code categories to make between-case comparisons.27 Co-authors (MTD & EEK) reviewed the summary table and agreed on the most illustrative examples of each theme for the manuscript. NVivo 10 was used to facilitate the coding process.28
Results
Of 174 participants contacted, 141 (82%) completed the yoga follow-up survey. Compared with non-respondents, yoga survey respondents were older (37 versus 33 years), more often male (72% versus 55%), more likely to have a 4-year college degree (59% versus 45%), and less likely to have chronic pain (36% versus 44%). Table 1 presents characteristics of study participants according to whether they reported yoga practice in the past year. Most reported past-year yoga practice (110, 78%) and were instructed to complete the full questionnaire.
Table 1:
Characteristics of survey participants
| Characteristic | Used yoga in past year N = 110 (78%) |
Did not use yoga past year N = 31 (22%) |
|---|---|---|
| Age, Mean (SE) | 37 (0.8) | 37 (1.3) |
| Male, % (N) | 69% (76) | 84% (26) |
| Survey conducted by phone, % (N) | 7% (8) | 13% (4) |
| Currently under orders from National Guard, % (N) | 37% (39) | 37% (11) |
| Currently in school, % (N) | 22% (23) | 17% (5) |
| Obtained 4 year degree, % (N) | 68% (71) | 50% (15) |
| Relationship Status, % (N) | ||
| Single, never married | 15% (16) | 10% (3) |
| Married | 76% (80) | 87% (26) |
| Living with partner, not married | 6% (6) | 3% (1) |
| In relationship, not living together | 3% (3) | 0% (0) |
| Chronic Pain, % (N) | 37% (41) | 58% (18) |
| PEG, Mean (SE) | 2.5 (0.2) | 2.7 (0.4) |
| Overall health Excellent/Very good, % (N) | 60% (63) | 33% (10) |
| Years of yoga, % (N) | ||
| Less than 2 years | 25% (27) | -- |
| Less than 5 years but longer than 2 years | 43% (47) | -- |
| Less than 10 years but longer than 5 years | 22% (24) | -- |
| Longer than 10 years | 11% (12) | -- |
| Months of yoga last year, Mean (SE) | 7.7 (0.4) | -- |
| Yoga frequency last month, % (N) | ||
| Not at all | 33% (36) | -- |
| About once last month | 23% (25) | -- |
| A few times last month | 25% (28) | -- |
| A few times a week | 15% (17) | -- |
| Daily or almost daily | 4% (4) | -- |
Of yoga practitioners, 98 (89%) completed all 22 items of the EPYQ properties of yoga practice section, 3 (3%) skipped all 22 questions, and the remaining 9 (8%) skipped one or two items. For the context of yoga practice section, 94 participants (85%) completed all 20 items and the remaining 16 participants skipped 3 to 6 items. Data were assumed to be missing at random and single variable analysis was performed with pairwise deletion.
Characteristics of yoga practitioners with and without chronic pain.
Table 2 presents characteristics and frequency of yoga practice according to presence or absence of chronic pain. Yoga practitioners with chronic pain were slightly older (mean age 39 versus 35 years, difference=3.9 years [95% CI: 0.7 to 7.1]) and less likely to be active in the National Guard (26% versus 44%, difference=20% [95%CI: 20% to 0.6%]) as compared to yoga practitioners without chronic pain. The yoga practitioners with chronic pain were less likely to report excellent or very good health compared to those without chronic pain (41% versus 71%, difference=−30% [95% CI: −49% to −11%]). Practice at least a few times in the last month was reported by 54% (n=22/41) of practitioners with chronic pain and 41% (n=28/69) of those without chronic pain; this difference was not statistically significant.
Table 2:
Characteristics of yoga practitioners with chronic pain compared to yoga practitioners without chronic pain
| Characteristic | Chronic Pain N = 41 (37%) |
No Chronic Pain N = 69 (63%) |
Difference [95% CI] |
|---|---|---|---|
| Age, Mean (SD) | 39.1 (10.2) | 35.3 (6.7) | 3.9 [0.7 to 7.1] |
| Male, % (N) | 71% (29) | 68% (47) | 2.6% [−15% to 20%] |
| Currently under orders from National Guard, % (N) | 26% (10) | 44% (29) | −20% [−20% to −0.6%] |
| Currently in school, % (N) | 18% (7) | 16% (10) | 2.3% [−13% to 17%] |
| Obtained 4 year degree, % (N) | 64% (25) | 70% (46) | −5.6% [−24% to 13%] |
| Relationship Status, % (N) | |||
| Single, never married | 13% (5) | 17% (11) | 0.31† |
| Married | 85% (33) | 71% (47) | |
| Living with partner, not married | 3% (1) | 8% (5) | |
| In relationship, not living together | 0 | 5% (3) | |
| PEG, Mean (SD) | 4.1 (2.0) | 1.5 (1.6) | 2.7 [2.0 to 3.3] |
| Overall health Excellent/Very good,* % (N) | 41% (16) | 71% (47) | −30% [−49% to −11%] |
| Years of yoga, % (N) | |||
| Less than 2 years | 27% (11) | 23% (16) | 0.63† |
| Less than 5 years but longer than 2 years | 41% (17) | 43% (30) | |
| Less than 10 years but longer than 5 years | 17% (7) | 25% (17) | |
| Longer than 10 years | 15% (6) | 9% (6) | |
| Months of yoga last year, Mean (SD) | 7.8 (4.3) | 7.6 (4.0) | 0.3 [ −1.3 to 1.9] |
| Yoga frequency last month, % (N) | |||
| Not at all | 29% (12) | 35% (24) | 0.50† |
| About once last month | 17% (7) | 26% (18) | |
| A few times last month | 27% (11) | 25% (17) | |
| A few times a week | 22% (9) | 12% (8) | |
| Daily or almost daily | 5% (2) | 3% (3) | |
Excellent or Very good health versus Good/Fair/Poor health
Fisher’s exact test for trend
Table 3 and Table 4 present the results of EPYQ properties and characteristics of practice respectively, stratified by chronic pain status. Practitioners with and without chronic pain were similar in their high endorsements of breathwork (3.7 with chronic pain versus 3.6 without, scale of 1 [“not at all”] to 5 [“very large amount”]) and weak endorsement of spirituality (1.5 versus 1.5). These findings indicate that breath practices are more universally practiced in this sample than spirituality practices, with no differences across levels of chronic pain. Practitioners with chronic pain received less individual attention from an instructor (1.5 versus 1.9) and used less-active postures (2.9 versus 3.3) with lower physicality (2.8 versus 3.1). As for the context of practice, practitioners with and without chronic pain more frequently practiced at home than in gyms or yoga studios, but those with chronic pain practiced at yoga studios far less frequently (18% practiced often or very often at yoga studios) than those without chronic pain (41%). Similarly, practitioners with chronic pain less frequently practiced with a yoga instructor than those without chronic pain (38% versus 61%) and tended to practice with smaller groups (28% versus 42% practice with 8 to 20 other people; 24% versus 41% with 2 to 8 other people). Similar frequency was observed for practice led by videos, books and apps. Practitioners with chronic pain more frequently practiced by themselves (77% versus 67%) and were self-directed (47% versus 36%). Compared with practitioners without chronic pain, those with chronic pain less often practiced for longer than an hour (26% versus 52%).
Table 3:
Responses to the Essential Properties of Yoga Questionnaire Short Form Part 1
| Chronic pain status | Difference [95% CI] | ||||
|---|---|---|---|---|---|
| EPYQ Short Form Part 1: Context Item |
Total sample |
Chronic Pain |
No Chronic Pain | ||
| N = 110 (100%) |
N = 41 (37%) |
N = 69 (63%) | |||
| How often at: % (N) | |||||
| A yoga studio or other yoga center | 33% (33) | 18% (7) | 41% (26) | −23% [−40% to −5.5%] | |
| Gym, exercise facility or recreation center | 47% (47) | 42% (16) | 49% (31) | −7.1% [−27% to 13%] | |
| Residence or home | 70% (76) | 74% (29) | 68% (47) | 2.2% [−6.3% to 11%] | |
| Outside, in nature or at a park | 19% (19) | 16% (6) | 21% (13) | 6.2% [−11% to 24%] | |
| How often led by: % (N) | |||||
| A yoga instructor, in person | 52% (53) | 38% (15) | 61% (39) | −22% [−42% to 3.1%] | |
| Someone other than a yoga instructor, in person | 11% (11) | 16% (6) | 8% (5) | 8.0% [−5.4% to 21%] | |
| A video or audio recording | 50% (53) | 47% (18) | 52% (35) | −4.9% [−25% to 15%] | |
| A book / booklet / pamphlet | 9% (9) | 11% (4) | 8% (5) | 2.6% [−9.2% to 14%] | |
| An app | 17% (18) | 21% (8) | 15% (10) | 5.7% [−10% to 21%] | |
| Self-directed (from memory or other) | 40% (41) | 47% (18) | 36% (23) | 11% [−8.3% to 31%] | |
| How often with: % (N) | |||||
| Many other people (20+) | 13% (13) | 5% (2) | 17% (11) | −12% [−34% to −0.0%] | |
| More than a few other people (8-20 other people) | 37% (38) | 28% (11) | 42% (27) | −14% [−33% to 4.6%] | |
| A few other people (2-8) | 34% (35) | 24% (9) | 41% (26) | −17% [−35% to 1.2%] | |
| One other person | 29% (30) | 21% (8) | 34% (22) | −13% [−31% to 4.1%] | |
| Alone / by yourself | 71% (75) | 77% (30) | 67% (45) | 9.8% [−7.6% to 27%] | |
| How often: % (N) | |||||
| One hour or longer | 43% (43) | 26% (10) | 52% (33) | −26% [−45% to −7.4%] | |
| At least 30 minutes, but less than 1 hour | 66% (69) | 65% (26) | 66% (43) | −1.2% [−20% to 18%] | |
| At least 10 minutes, but less than 30 minutes | 49% (51) | 53% (20) | 47% (31) | 5.7% [−14% to 26%] | |
| Less than 10 minutes | 22% (22) | 24% (9) | 21% (13) | 3.0% [−14% to 20%] | |
Study participants were asked to recall their yoga practice over the past 6 months when answering these questions. Percentages are the proportion of respondents endorsing Very Often/Often versus Sometimes/Rarely/Never. The first column is the results of the total sample, then results are stratified by chronic pain status. The final column presents the absolute differences (additive scale) between the chronic pain and non-chronic pain strata.
Table 4:
Responses to the Essential Properties of Yoga Questionnaire Short Form Part 2.
| EPYQ Short Form Part 2: Properties (α = 0.90) Mean (SD) |
Total sample |
Chronic Pain |
No Chronic Pain |
P * | SEM† | ||||
|---|---|---|---|---|---|---|---|---|---|
| N = 110 (100%) |
N = 41 (37%) |
N = 69 (63%) |
|||||||
| Breathwork (α = 0.83) | 3.7 (1.1) | 3.7 (0.9) | 3.6 (1.0) | 0.69 | 0.5 | ||||
| Placing one’s focus on the breath | 3.8 (1.1) | 3.8 (1.0) | 3.7 (1.2) | ||||||
| Deep breathing (full inhalation and exhalation) | 3.7 (1.1) | 3.8 (1.0) | 3.6 (1.2) | ||||||
| Linking breathing with movement | 3.6 (1.0) | 3.6 (1.0) | 3.6 (1.2) | ||||||
| Physicality (α = 0.83) | 3.0 (0.9) | 2.8 (0.8) | 3.1 (0.9) | 0.08 | 0.4 | ||||
| Vigorous activity or physical exertion | 2.6 (1.1) | 2.4 (1.0) | 2.6 (1.2) | ||||||
| Challenging one’s physical balance | 3.1 (1.1) | 2.9 (1.0) | 3.3 (1.1) | ||||||
| Challenging one’s physical flexibility | 3.4 (1.0) | 3.3 (1.1) | 3.6 (1.0) | ||||||
| Challenging one’s physical strength | 2.9 (1.1) | 2.7 (1.0) | 2.9 (1.2) | ||||||
| Active Postures (Asana) (α = 0.60) | 3.1 (0.8) | 2.9 (0.9) | 3.3 (0.7) | 0.01 | 0.5 | ||||
| Modifications to increase the difficulty of a pose | 2.9 (1.1) | 2.6 (1.1) | 3.1 (1.1) | ||||||
| Holding poses (longer than a few seconds) | 3.8 (1.0) | 3.5 (1.1) | 4.0 (0.8) | ||||||
| Inverted poses (poses where the head is below the heart or hips) | 2.7 (1.1) | 2.5 (1.0) | 2.9 (1.1) | ||||||
| Mental & Emotional Awareness / Release (α = 0.90) | 2.8 (1.2) | 2.8 (1.3) | 2.8 (1.1) | 0.82 | 0.4 | ||||
| Allowing or being present to emotions or feelings that come up while doing yoga | 2.4 (1.3) | 2.4 (1.5) | 2.4 (1.2) | ||||||
| Mental relaxation | 3.3 (1.3) | 3.3 (1.3) | 3.3 (1.3) | ||||||
| Emotional release | 2.6 (1.5) | 2.6 (1.5) | 2.7 (1.3) | ||||||
| Individual Attention (α = 0.63) | 1.7 (0.9) | 1.5 (0.6) | 1.9 (1.1) | 0.03 | 0.5 | ||||
| Giving individual attention or feedback (instructor or assistants) | 1.9 (1.2) | 1.7 (1.1) | 2.0 (1.3) | ||||||
| Physically assisting students with poses | 1.6 (1.0) | 1.3 (0.5) | 1.8 (1.1) | ||||||
| Spirituality (α = 0.78) | 1.5 (0.7) | 1.5 (0.8) | 1.5 (0.7) | 0.85 | 0.3 | ||||
| Chanting and/or reciting mantras or saying “OM” | 1.3 (0.7) | 1.2 (0.6) | 1.4 (0.8) | ||||||
| Spiritual readings, quotes, sayings, teachings, or ideas | 1.5 (0.8) | 1.5 (0.9) | 1.5 (0.8) | ||||||
| Reference to a connection to a higher power or something greater than oneself (Spirit, God, Universe) | 1.7 (1.0) | 1.8 (1.2) | 1.6 (0.9) | ||||||
| Meditation & Mindfulness (α = 0.87) | 2.4 (1.1) | 2.3 (0.9) | 2.4 (1.1) | 0.52 | 0.4 | ||||
| Quieting the mind | 3.0 (1.2) | 3.0 (1.2) | 3.0 (1.2) | ||||||
| Meditation (Dhyana: deep absorptive meditation) | 2.1 (1.3) | 2.1 (1.3) | 2.2 (1.3) | ||||||
| Withdrawal of the senses (Pratyhara: directing the attention from the external toward an internal awareness) | 2.0 (1.3) | 2.0 (1.3) | 2.1 (1.4) | ||||||
| Concentration (Dharana: a state of complete absorption or concentration/focus of the mind) | 2.4 (1.3) | 2.4 (1.3) | 2.3 (1.2) | ||||||
P-value of T-test of equality of means with degrees of freedom corrected for unequal variances
Standard error of measurement (SD × α1/2)
Together, these results indicate that the distinguishing features of yoga practice for persons with chronic pain were gentler and independent practice, whereas for those without chronic pain the distinguishing features were more active practice at yoga studios. Other properties of yoga practice did not differ between the two groups.
Qualitative results
The 11 participants who completed in-depth interviews included 6 men and 5 women, aged 28 to 54 years (mean=39, SD=8). Seven had chronic pain. Four participants primarily practiced yoga with an instructor, five primarily practiced on their own, and two regularly practiced both with an instructor and on their own.
Qualitative data analysis focused on exploring comments related to two key differences identified in the quantitative phase between yoga practitioners with and without chronic pain: the physicality of practice and practicing independently. We identified five themes related to these findings, described below.
Independent versus group practice
One theme—self-consciousness in group practice—supported independent practice for those with chronic pain. A second theme—convenience—favored independent practice for those with and without chronic pain. A third theme—positive group dynamics—favored practice in a group or yoga studio for participants without chronic pain.
Convenience
Participants with and without chronic pain spoke about the convenience of being able to practice yoga on their own and when they needed it. For some participants, practicing independently was a valuable self-management strategy to address pain or other symptoms. For example, one participant with chronic pain described how he used yoga:
I can kind of use it now if I feel my back hurting; I know more poses to do to loosen it up again. […] I got to know my body well enough that I can just perform maintenance kind of on the spot. [Participant 1]
A participant without chronic pain described using independent yoga practice when needed to promote personal wellbeing:
I have a mat and I bought some blocks and things like that. And the more I did it, the better I felt. So, I’m like, okay, now I’m just going to have to take the time to do that. So, even if it’s like 10 minutes. Because I said, gosh, I can’t really squeeze in like 45 minutes when I work 12 hours. I just don’t want to take another freaking hour, you know, I want to sleep. So, [my instructor] would show me quick 10 minute little ones to help me relax or get me to fall asleep or something like that. [Participant 3]
Several participants commented that alternative formats of delivery were also convenient. One participant with chronic pain described her use of different formats:
So I do at least one class and then I’ve got an app thing that’s got like a bunch of different classes from beginner to more advanced and they have one that’s post-running that I’ll do after I use like the elliptical or just a basic stretching or even a little back pain. […] So I can use something like that or a DVD when I can’t get to the gym or they don’t have a class. [Participant 4]
Self-consciousness in group practice
Only participants with chronic pain commented on feeling self-conscious in group yoga settings. Participants expressed a variety of concerns about joining groups of people with more yoga experience or fewer physical health challenges. One participant with chronic pain described how comparison with more agile yoga practitioners affected him:
I’ve found that it’s just better to be by myself, be self-aware and do it on my own, rather than in a group setting. Because it almost makes it worse when you’re looking over and you see somebody your same age and they can do all this stuff and you’re struggling to even put your sock on. [Participant 9]
Some participants reported their concerns were eased after becoming more experienced with yoga practice.
I would like to do yoga in a group. And I feel like now that I’ve done a little bit at home, I’d be a little bit better. Like, if there was a beginners’ kind of class. Because some people are so good and I would just feel silly, you know, go in the back of the room or something. So, yeah, if it was people on more my level, I would feel comfortable. [Participant 2]
I look a little more like I belong there. You know there are the yogi people that… I’m just not one of those people, but I try to fit in a little bit. I kind of like to go in the corner instead, but I do feel like I know their moves a little bit more. [Participant 5]
Other participants dismissed concerns about self-consciousness in group yoga. One participant without chronic pain commented:
I’ve done it in groups and it’s been fun. We always think that people are staring at you or looking at you. They don’t care what you wear or what you look like or whatever. So, the groups I’ve gone into have been positive. [Participant 3]
Positive group dynamics
All participants who attended group yoga classes reported that group dynamics were important aspects of the experience. For example:
It’s always been a very positive thing for me to go do. I could be having a bad day and I’ll feel like, you know what, I might go to a yoga class and just the environment because […] when I go I feel the support from the other people. […] So it’s kind of the social aspect of it, too, and just talking to people. That’s very helpful. [Participant 10]
Some participants described the group dynamic as contributing to accountability and persistence with practice. For example:
I couldn’t do [yoga] on my own. I mean if [your friends] don’t see you, they’ll ask where you’re at or the instructor will say everybody’s in their right spot—because everybody knows that my spot is back there; don’t get in my spot. [Participant 6]
[Yoga] is the one group exercise I like—minus sports—being with a group because, again, I’m very competitive, so it helps me get through it. I don’t like to do it by myself […] because I know I’m just too distracted and I don’t get in the moment when I know I have dirty dishes or something I’m looking at. [Participant 5]
On the other hand, some group yoga participants reported challenges associated with practice in a group setting. For example:
Yoga by myself is difficult. […] But I find the group to be distracting for the mental part… when you’re in a group, it seems like it’s harder to focus on your own—there are outside distracters, like other people. [Participant 7]
Physicality of yoga practice
The second key finding explored in qualitative analysis was the relationship between chronic pain and physical intensity of yoga practice. We identified the following two emergent themes related to this topic: modifying yoga practice to accommodate pain-related limitations and using yoga to cope with pain.
Modifying yoga practice
Participants reported they avoided aspects of yoga practice that aggravated their pain. One participant with chronic pain described how she worked within her personal limits:
[W]hen I first started, obviously, some of the poses and stretches are hard. If you’ve never done them, they’re going to be difficult. So, that was something definitely when I first started and had the back pain, learning to do some of those new poses and stretches. At first, they would kind of hurt, but with anything, you take it at your own pace and moderation. [Participant 11]
Many participants felt it was important to have an instructor who was knowledgeable about pain and physical limitations. For example, one commented:
The class that I did at the VA, because they were directing at, “okay, you have back pain, this is how we’re going to manage it.” But the classes that are offered in the community, they don’t have ones that are like that. It’s more like yoga for beginners, yoga for advanced people, you know what I mean? They usually give you alternate things to do but it’s really, really difficult to be in a class when you don’t know if you’re going to be able to do it for two minutes or 30 minutes. [Participant 9]
Others felt able to modify on their own. One such participant said:
I have to put maybe extra padding like an extra towel or something under that knee if I have to go into a pose where you’re on your hands and knees. […] But it really hasn’t been very hard. I watch the video and I do it how I can do it. [Participant 2]
Yoga for coping with pain
Participants with chronic pain expressed that practicing yoga helped them cope.
It empowered me, whereas before I felt like some kind of crippled victim that maybe needed surgery or going to the VA for physical therapy or whatever. Now I really do feel like I have the tools to prepare my body. [Participant 1]
I think [yoga] helps to gather your mindset and kind of put yourself in a calm, relaxed place. […] [Pain]’s kind of like a two-year-old. It’s easier to manage them if they’re in a relaxed, calmed mindset rather than completely worked up and…you know what I mean? […] I think [yoga] kind of forces you into it. It makes you concentrate on your breathing and your overall mindset. I think it makes you more bodily aware. [Participant 9]
Discussion
We found that yoga practitioners with chronic pain more often practiced independently at home and used gentler practices. In-depth interviews suggested potential explanations for these findings, including self-consciousness in group settings and need for yoga modifications among practitioners with chronic pain.
On several dimensions, the yoga practices of study participants with and without chronic pain were similar, including a large focus on breathwork, a moderate focus on mental & emotional awareness and mindfulness, and little focus on spirituality. Most practice in both groups was alone, at home, with duration between 10 minutes and 1 hour. Yoga practitioners with chronic pain had more severe pain and worse self-rated overall health, which may help explain the findings of lower physicality and more less group class participation.
We identified potential pain-related barriers to participation in group yoga practice. These barriers may be important because practicing in a group is an enjoyable part of yoga practice for many people and may contribute to effectiveness of yoga interventions. For example, a randomized yoga trial29 found relationships with teachers and classmates as a facilitating factor in yoga class attendance. Most participants were practicing yoga at home by themselves, especially those with chronic pain. Previous population studies have similarly found higher rates of home practice than studio practice,30 but have not reported how chronic pain may affect practice location. Research on yoga has focused on instructor-delivered group practice and most published yoga trials did not included any home practice.31 To increase relevance for patients with pain, future research should evaluate effectiveness of yoga interventions delivered using formats such as telehealth32 or apps.
A secondary goal of this project was to describe implementation of the EPYQ-SF self-report measure. The original EPYQ was developed for characterization of yoga in clinical research. The version used in this study fills a need for an instrument that can efficiently capture yoga practice characteristics in community and clinical populations. Prior research found high correlations between reports of students and of expert raters on the seven domains of the EPYQ-SF.14 In this study, the questionnaire was easily understood by participants, all items had high rates of completion, and subscales had good internal consistency. As a practical self-report measure, EPYQ-SF may help facilitate needed research on effectiveness of real-world yoga practices.
This study contributes needed data on use of yoga among veterans. Veterans experience elevated rates of chronic pain and high rates of pain comorbidities.33-36 Prior studies of yoga for chronic pain have often been conducted with samples that have different demographics and comorbidities and that may not generalize well to veteran populations.37 Consequently, researchers have called for more studies on yoga in military service member and veteran populations.31,38-40
This study has several limitations. First, results are based on recall of past yoga practice. Participants might not accurately recall their practice over the course of 6 months or a year and more recent experiences may bias recall. The relatively small sample size limited hypothesis testing as only large effect sizes would be detectable. The standard error of measurement of the individual subscales ranged between 0.3 and 0.5, which is an estimate of the minimum difference that could be considered important or meaningful.41 It is difficult to make further assertions about the importance of small differences in scale means without further investigation. Also, findings of these study may not generalize to other populations. As mentioned previously, participants were homogeneous with respect to military service and of origin in the midwestern United States. With respect to yoga practice, it is possible that this sample is less representative of those for whom yoga was not beneficial, since participants may have tried yoga longer than a year ago and discontinued when it did not help, and consequently would not have been captured in this study. The mixed design sheds light on these issues and strengthens the external validity.
In summary, study findings suggest persons with chronic pain have potentially unique needs and preferences that may be important to consider when designing or implementing yoga interventions for pain. Specifically, researchers and clinicians may want to consider providing alternative delivery formats, addressing self-consciousness and facilitating beneficial group dynamics. Furthermore, our results support efforts connect skilled instructors with potential participants with chronic pain as they may particularly benefit from instruction on modifications, encouragement and de-stigmatization of their limitations. A cohort of participants with pain may also facilitate this. This study also supports use of the EPYQ-SF as a self-report measure in future yoga research. With the growing popularity of yoga,4 research that captures the experience of yoga practitioners with a variety of medical concerns and reasons for practice is increasingly important.
Supplementary Material
Acknowledgments:
The authors would like to acknowledge Chris Erbes and Erin Amundson for their assistance with conducting qualitative interviews, Andrea Cutting for technical assistance with the survey form and Emily Hagel-Campbell for her assistance with database management.
This research was supported by the NIH grant R01AT008387 (Polusny & Krebs, Co-PIs). M. Donaldson was supported by NIH grant F30AT009162 (Donaldson, PI), and NIH MSTP grant T32GM008244. This material is the result of work supported with resources and the use of facilities at the Minneapolis VA Healthcare System, Minneapolis, MN.
Footnotes
The authors disclose no conflicts of interest.
Contributor Information
Melvin T Donaldson, Medical Scientist Training Program, University of Minnesota Medical School, Minneapolis, MN.
Dianne Neumark-Sztainer, Division of Epidemiology and Community Health, University of Minnesota School of Public Health, Minneapolis, MN.
Joseph E Gaugler, Division of Health Policy & Management, School of Public Health, University of Minnesota, Minneapolis, MN.
Erik J Groessl, VA San Diego Healthcare System; and Department of Family Medicine and Public Health, University of California San Diego, San Diego, CA.
Shannon M Kehle-Forbes, Minneapolis VA Healthcare System and University of Minnesota Medical School, Minneapolis, MN.
Melissa A Polusny, Minneapolis VA Healthcare System and University of Minnesota Medical School, Minneapolis, MN.
Erin E Krebs, Minneapolis VA Healthcare System and University of Minnesota Medical School, Minneapolis, MN.
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