Research-Proven Yoga

Yoga Research

Yoga is now recommended as a first step to managing low back pain. This social enterprise website’s associated research project contributed significantly to the body of evidence.  The distinct evidence-based 12-week ‘Yoga for Healthy Lower Backs’ specialised course used in this research is available throughout the UK.


1a. Effectiveness Paper – YHLB Trial

This trial and research paper is the reason for this website

‘Yoga for Chronic Low Back Pain: A Randomized Trial’  Helen E. Tilbrook, Helen Cox, Catherine Hewitt, Arthur Ricky Kang’ombe, Ling-Hsiang Chuang, Shalmini Jayakody, John Aplin, Anna Semlyen, Alison Trewhela, Ian Watt, David J. Torgerson Annals of Internal Medicine 2011 (Nov. 1st 2011, Vol. 155, No.9, 569-578).
View a 4-minute yoga video produced for Annals of Internal Medicine for use alongside the full results paper at  (and by following the link from our website’s Home Page to The University of York’s yoga trial website).
Design and Methods This is the largest trial to date into the effectiveness of yoga as a treatment for chronic and recurring low back pain.  This multi-centre, intention-to-treat, randomized controlled trial was carried out by York Trials Unit, The Department of Health Sciences, The University of York, UK.  313 adults aged 18-65 years old were recruited from 39 GP practices in Cornwall, London, Manchester and York and were allocated to either the yoga group (n=156) or usual care group (n=157).  Alison Trewhela and John Aplin represented Iyengar Yoga Association UK and Anna Semlyen represented the British Wheel of Yoga on the trial management team and 20 teachers (10 from each organisation) were trained in the yoga programme designed by Alison Trewhela.  Alison and Anna co-authored a comprehensive Students’ Manual and a Teachers’ Manual as well as recording a 4-track Relaxations CD to enable teachers to be trained in the yoga programme and to enable yoga participants to practice at home.  The 12-class ‘Yoga for Healthy Lower Backs’ course developed especially for the trial was delivered as 16 courses of weekly, 75-minute classes with an average allocation of 10 per class.  Home practice was encouraged, ideally 30 minutes daily or at least twice a week.  Students were given the Relaxations CD at the first class as well as pain-relieving poses.  They had 2 foundational CORE yoga sequences to alternately practice at home and then a further 2 PROGRESSIVE yoga sequences were added in the second half of the course.  Outcomes were measured at 3 months (the end of the yoga 12-week intervention), at 6 months, and at 12 months.  It was generously funded by the charity Arthritis Research UK.  For more details of the ‘Yoga for Healthy Lower Backs’ programme developed and used successfully  in this trial, please take a good look at the rest of this website.
Outcome Measures The primary outcome measure was the Roland Morris Disability Questionnaire (RMDQ) which measures back function and the ability of patients to have the confidence to return to everyday activities at home, at work and socially.  Secondary measures were the RMDQ at 6 months and 12 months and also at 3, 6 and 12 months the Aberdeen Back Pain Scale (ABPS), pain and self-efficacy (PSEQ), general health scores (SF12 Health Survey and the EuroQol-5D).  A separate paper will be published into the cost-effectiveness of yoga as a treatment.
Results The average duration of back pain was 10 years, 77% of those had current back pain, the majority of the trial participants were middle-aged and two thirds were female.  60% of those allocated to the ‘Yoga for Healthy Lower Backs’ programme attended 3 of the first 6 classes and at least 3 other classes; 21 allocated to the yoga group did not attend any classes nor had any contact with a yoga teacher.  The yoga group showed significantly better improvements than the usual care group according to the RMDQ at 3, 6 and 12 months.  The yoga group also had better Pain and Self-Efficacy scores at 3 and 6 months.  Frequency of home practice was 82% at 3 months, 65% at 6 months and 60% at 12 months amongst those in the yoga group and the average frequency was twice per week.  Home practice may account for why the effects of the yoga lasted 9 months after the yoga classes had finished.  According to a graph showing this yoga comparative to other forms of treatment researched as a treatment using similar outcome measures, yoga is shown to be more effective than exercise, manipulation, exercise and manipulation combined, cognitive behavioural therapy and some measures of the Alexander Technique (yoga was better than 6 sessions, but not as good as 24 individual sessions).
Conclusion It was found that offering ‘The Yoga for Healthy Backs’ programme to adults with chronic and recurrent low back pain led to greater improvements in back function than usual care for up to 12 months.  Yoga appears to be a safe and effective treatment that clinicians should consider recommending for patients with a history of low back pain.

Click here to visit the ‘Annals of Internal Medicine’ – American College of Physicians website for full research results paper.

1b. Cost-Effectiveness paper – YHLB Trial

‘A Pragmatic Multi-centred Randomized Controlled Trial of Yoga for Chronic Low Back Pain: Economic Evaluation’ Spine Journal 15th August 2012  Chuang LH, Soares MO, Tilbrook H, Cox H, Hewitt CE, Aplin J, Semlyen A, Trewhela A, Watt I, Torgerson DJ.

The University of York, Arthritis Research UK-funded randomised control trial found that the ‘Yoga for Healthy Lower Backs’ yoga intervention (12-class ‘Yoga for Healthy Lower Backs’ course taught by qualified yoga teachers trained in how to deliver the yoga programme, Relaxations CD, book, home practice sheets) was not only safe and effective for those with chronic low back pain, but it furthermore analysed health economics data and found it would be likely to be cost-effective both within the UK NHS, workplaces and within society.   This assumed the cost of the yoga intervention, including educational resources, to be £292 per person.  During the 12 months studied, those in the yoga group had an average of only 3.83 days off work compared to 12.29 in the non-yoga group (usual care).  Sensitivity analyses suggest the same results – that a yoga intervention is likely to be cost-effective in both perspectives.
‘Conclusion. On the basis of this trial 12 weekly group classes of specialised yoga is likely to be a cost-effective intervention for treating patients with chronic or recurrent low back pain.’
‘In summary, the results of the economic evaluation support the use of 12 weekly group classes of specialized yoga for treating patients with chronic and recurrent low back pain within an NHS and non-NHS setting.’

Link to University of York and Arthritis Research UK’s Press Statement (Aug 16th 2012):’

Cost-Effectiveness Press Release Link to The University of York and Arthritis Research UK’s Press Statement (Aug 16th 2012) here

Link to Backcare UK charity’s Talkback magazine featuring ‘Yoga for Healthy Lower Backs’ (Page 14)

Past research trials

concerned with yoga for low back pain are presented here for educative purposes, in order to show the research background to our yoga trial mentioned above.


2.  Williams K, Abildso C, Steinberg L, Doyle E, Epstein B, Smith D et al

‘Evaluation of the Effectiveness and Efficacy of Iyengar Yoga Therapy on Chronic Low Back Pain’.               Spine 2009; 34(19): 2066-2076

Design and Methods In this intention-to-treat randomised controlled trial carried out in the USA, 90 subjects were randomized to either the yoga group or the control group receiving standard medical care.  The yoga groups were taught in four cohorts of 9-16 and participated in twice-weekly 90 minute Iyengar Yoga classes taught by an experienced  Iyengar Yoga teacher along with two assistants.  They were encouraged to practice at home for 30 minutes a day on non-class days.  The yoga classes continued for 24 weeks (48 classes) and outcomes were measured at 12 weeks (halfway through the yoga intervention), 24 weeks (immediately after the intervention) and 48 weeks (6 months after completion of the intervention).

Outcome measures were the Oswestry Disability Questionnaire, a Visual Analog Scale, the Beck Depression Inventory and a pain medication-usage questionnaire.  The non-yoga group were telephoned monthly for their prompting of follow-up measurements.

Results Significantly greater reduction in functional disability and pain intensity were observed in the yoga group when compared to the control group at 24 weeks.  A significantly greater proportion of yoga subjects also reported clinical improvements at both 12 and 24 weeks.  Depression was significantly lower in yoga subjects.  Although slightly less than at 24 weeks, the yoga group showed statistically significant reductions in functional disability, pain intensity and depression compared to standard medical care at the 6-months post-yoga-intervention time-point.  The changes in functional disability from intention-to-treat analysis (11.9% at 12 weeks and 29.0% at 24 weeks) compared favourably with the results of a 6-week Hatha yoga intervention (Galantino M et al 2004 ) (15.3%).  The per-protocol functional disability results of study completers (n=31) (improvements of 20.8% at 12 weeks and 42.9% at 24 weeks) show even more promise in comparison with other studies using similar analyses and instruments.  For example, a 6-week Pilates intervention showed only an 8.1% improvement  (Gadwell V et al 2006); those in a 10-week exercise intervention showed a 48.3% improvement (O’Sullivan P et al 2006); those in a 10-week lumbar stabilisation intervention showed a 28.4% improvement (Shaughnessay M et al 2004).

Conclusion Yoga improves functional disability, pain intensity, and depression in adults with chronic low back pain.  There was also a clinically important trend for the yoga group to reduce their pain medication usage compared to the control group.’


3.  Williams K, Petronis J, Smith D, Goodrich D, Wu J, Ravi N, Doyle Jr E, Juckett G, Kolar M, Gross R, Steinberg L

‘Efffect of Iyengar Yoga Therapy for Chronic Low Back Pain’    2005   Pain 115 107-117

Design and Methods In this US study 60 participants were randomised equally between a yoga group receiving 16 weeks of weekly 90 minute classes of specialised Iyengar Yoga taught by an experienced teacher and an educational group receiving 16 weekly back care newletters.  Yoga participants (of which 24 were considered to have completed the yoga intervention and 22 reached the 3 months’ post-intervention point) were asked to practice at home for 30 minutes 5 times a week.

Outcome measures were the Tait Pain Disability Index (functional disability), Short Form McGill Pain Questionnaire (clinical pain), Tampa Scale of Kinesiophobia (Fear of Movement), Jensen Survey of Pain Attitudes (pain attitudes), Robinson Coping Strategies Questionnaire, Back Pain Self-Efficacy, Saunders Digital Inclinometer (spinal range of movement), pain medication usage.

Results Analyses showed significant reductions in pain intensity (64%), functional disability (77%), and pain medication usage (88%) in the yoga group at the post-intervention 16 week and 3 months’ post-intervention (approx. 29 weeks total) follow-up measurements.

Conclusion These preliminary data indicate that the majority of self-referred persons with mild chronic low back pain will comply to and report improvement on medical and functional pain-related outcomes from Iyengar yoga therapy.’


4.  Sherman K, Cherkin D, Erro J, Miglioretti D, Deyo R

‘Comparing Yoga, Exercise, and a Self-Care Book for Chronic Low Back Pain’    2005                                       Annals of Internal Medicine 143:849-856

Design and Method In this US intention-to-treat randomised controlled trial 101 participants were randomly allocated to 3 groups: 12 weekly 75-minute classes of specially devised viniyoga yoga group (36 participants), 12 weekly 75-minute exercise classes designed by a physical therapist group (35) and the Self-Care Book group (30).

Outcome measures were the Roland Disability scale, Bothersomeness scale, Short Form-36 Health Survey (general health status), degree of restricted activity, and medication usage.  Participants in the yoga practised on average 3 times a week up until the 26 week final follow-up point.

Results Most participants in the yoga group (and also in the exercise group) said that they would be ‘very likely’ to continue their yoga or exercise practice in the future, but twice as many yoga class participants said they would ‘definitely recommend yoga’ classes to others.  Disability decreased in both the yoga and the exercise group at all follow-up measured points (6 weeks, 12 weeks and 26 weeks) and the yoga group (although not clinically significant) had significantly greater improvements than the exercise group at 12 weeks.  Between weeks 12 and 26 bothersomeness symptoms continued to improve only in the yoga group (whereas symptoms worsened in the exercise and book group).  At 6 and 26 weeks, the yoga group experienced clinically and statistically significant reductions in symptoms compared with the book group.  Medication use decreased most sharply in the yoga group.  The study suggests that appropriate yoga taught by experienced yoga teachers is safe and effective as a treatment.

Conclusion Yoga was more effective than a self-care book for improving function and reducing chronic low back pain, and the benefits persisted for at least several months.’


5.  Saper R, Sherman K, Cullum-Dugan D, Davis R, Phillips R, Culpepper L

‘Yoga for Chronic Low Back Pain in a Predominantly Minority Population: A Pilot Randomized Controlled Trial’      2009    Alternative Therapies 15(6):18-27

Design and Methods This small US pilot randomized controlled trial studied 30 participants allocated to 12 once week yoga hatha yoga class group compared to a wait-list usual care control group.

Outcome measures were  pain scores, Roland-Morris Disability Questionnaire, analgesic use, global improvement and quality of life (SF-36).

Results Mean pain scores for yoga decreased from baseline to 12 weeks (6.7 to 4.4) compared to usual care which decreased from 7.5 to 7.1. Mean disability scores for yoga decreased from 14.5 to 8.2 compared to usual care which decreased from 16.1 to 12.5.  At 12 weeks, yoga compared to usual care participants reported less analgesic use (13% vs 73%), less opiate use (0% vs 33%) and greater overall improvement (73% vs 27%).

Conclusion A yoga study intervention in a predominantly minority population with chronic low back pain was moderately feasible and may be more effective than usual care for reducing pain and pain medication use.’


6. Groessl E, Weingart K, Aschbacher K, Pada L, Baxi S

‘Yoga for Veterans with Chronic Low Back Pain’     Journal of Alternative Complementary Medicine   (2008) 14(9): 1123-1129

Design and Methods This small US trial studied 32 veterans participating in 10 weeks of yoga.  Participants were mostly males with an average age of 55.

Outcome measures Pain, depression, energy/fatigue, health-related quality of life, and yoga programme satisfaction were measured via questionnaires.

Results Significant improvements were found in pain, depression, energy/fatigue, Short Form-12 Mental Health.  The amount of improvement correlated to the number of yoga sessions attended and the amount of yoga practised at home.

Conclusion Preliminary data suggest that a yoga intervention for VA (Veterans’ Administration) with chronic back pain may improve the health of veterans. However, the limitations of the pre-post study design make conclusions tentative.  A larger, randomized controlled trial of the yoga program is planned.’


7.  Tekur P, Singphow C, Nagendra H, Raghuram N

‘Effect of Short-Term Intensive Yoga Program on Pain, Functional Disability and Spinal Flexibility in Chronic Low Back Pain: A Randomized Control Study.’     The Journal of Alternative and Complementary Medicine (2008)  14(6): 637-644

Design and Method This Indian wait-list randomized controlled trial compared a 1-week intensive yoga programme residential at an integrated health centre compared to physical exercise (the control group) on pain and spinal flexibility of 80 (mostly male) chronic low back pain subjects.  The yoga consisted of postures designed for lessening back pain, breathing, didactic and interactive sessions on philosophical concepts of yoga.  Both groups were matched for time and attention and the control exercise group also had didactic and interactive sessions on lifestyle changes.

Outcome Measures Pain-related outcomes were measured using  the Oswestry Disability Index and spinal flexibility by using a goniometer pre and post intervention.

Results There were significant improvements in the Oswestry Disability Index scores for the yoga group compared with the exercise group.  Spinal flexibility improved in both groups, but the scores for the yoga group had greater improvement compared to the exercise group in spinal flexion, extension, and lateral extension.

Conclusion Seven days of a residential, intensive yoga-based lifestyle program reduced pain-related disability  and improved spinal flexibility in patients with chronic low back pain better than a physical exercise regimen.’


8.  Galantino M, Bzdewka T, Eissler-Russo J, Holbrook M, Mogck E, Geigle P, Farrar J

‘The impact of modified Hatha yoga on chronic low back pain: a pilot study’      Alternative Therapies in Health and Medicine (2004)   10(2): 56-9

Design and Method In this randomized study, carried out as a pilot to evaluate the possible design of a 6-week yoga programme of modified Hatha yoga for chronic low back pain subjects, 22 subjects (the majority of them females) were randomized to either yoga or the control group.  The yoga group received 1 hour of yoga tuition twice a week for the 6 weeks.

Outcome measures were functional measures such as forward reach and sit and reach measurements, and the Oswestry Disability Index and the Beck Depression Inventory questionnaires plus guiding questions for qualitative data analysis on questions such as the impact of yoga on life.

Results Potentially important trends in the functional measurement scores showed improvements in flexibility and balance as well as decreased disability and depression in the yoga group, but the pilot study was not powered to reach statistical significance.  Analysis of qualitative data showed that ‘group intervention as motivation’ and the fact that ‘yoga fostered relaxation and new awareness/learning’ were frequent responses from the yoga group participants.

Conclusion A modified yoga-based intervention may benefit individuals with chronic low back pain, but a larger study is necessary to provide definitive evidence.  Also, the impact on depression and disability could be considered as important outcomes for futher study.  Additional functional outcome measures should be  explored.  This pilot study supports the need for more research investigating the effect of yoga for this population.’


9. Williams K, Steinberg L, Petronis J

‘Therapeutic Application of Iyengar Yoga for Healing Chronic Low Back Pain’     International Journal of Yoga Therapy   (2003)  No. 13

Design and Method This article described the rationale and method for the therapeutic application of Iyengar Yoga for chronic low back pain and described a randomized controlled pilot trial evaluating the efficacy of a 16-week program of Iyengar Yoga therapy in 57 (mostly female) subjects with non-specific chronic low back pain compared to a control back pain educational group.

Results Subjects in the yoga group reported significant improvements at the end of the 16-week yoga program compared to the control group.  These results included 77% reduction in functional disability, 64% decrease in present pain, 10% increase in perceived control over pain and a trend toward greater pain tolerance to pressure compared to controls at specific locations in the low back and pelvis (including standard trigger point locations for r. and l. iliocostalis and r. gluteus medius).  Pain medication usage was significantly reduced in the yoga group compared to the control group – 88% of the subjects taking pain medication for low back pain at the start of the study either stopped or used less compared to 35% in the educational control group immediately after the 16 weeks.

Conclusions These preliminary data are important for a number of reasons.  They determined that the majority of self-referred persons with non-specific chronic low back pain would comply with Iyengar Yoga therapy.  Furthermore, a significant number of subjects reported improvement in pain-related outcomes from a 16-week program. From the variety of outcomes tested, present pain intensity, functional disability, perceived control over pain, and hip flexion were significantly improved and pain medication usage was decreased by Iyengar Yoga therapy.’


Alison Trewhela writes Chapter in 2013 book entitled ‘Methodologies for effectively assessing Complementary and Alternative Medicine (CAM) – Research Tools and Techniques’ edited by Mark Langweiler and Peter W McCarthy.

Alison Trewhela contributes to Delphi Study to inform future yoga research protocols and methodologies – Article: Establishing key components of yoga interventions for musculoskeletal conditions: a Delphi survey

Lesley Ward, Simon Stebbings, Karen J Sherman, Daniel Cherkin, G David Baxter
ABSTRACT: Evidence suggests yoga is a safe and effective intervention for the management of physical and psychosocial symptoms associated with musculoskeletal conditions. However, heterogeneity in the components and reporting of clinical yoga trials impedes both the generalization of study results and the replication of study protocols. The aim of this Delphi survey was to address these issues of heterogeneity, by developing a list of recommendations of key components for the design and reporting of yoga interventions for musculoskeletal conditions.
BMC Complementary and Alternative Medicine 06/2014; 14(1):196
‘Effectiveness of Iyengar yoga in treating spinal (back and neck)
pain: A systematic review’
Edith Meszaros Crow, Emilien Jeannot, Alison Trewhela
University of Geneva, Institute of Social and Preventive Medicine, Geneva, Switzerland, Master of Public Health


Yoga Trials into Conditions other than Low Back Pain

There has been research showing that yoga can be a useful and effective treatment for many other conditions, although much of this research has yet to be replicated with enough statistical power to prove that it is clinically significant.  They are often small studies, partly because in the past it has not been easy to get funding for larger studies, but these studies’ positive results nevertheless give us more than promising anecdotal evidence.

Yoga research trials and studies have shown yoga to be effective for the following conditions: Depression in Young Adults; Anxiety; Osteoarthritis of the Knees; asthma; stress-reduction; high blood pressure; carpal tunnel syndrome; sleeping improvements; and more.