Complementary Therapies in Medicine 30 (2017) 61–66

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Complementary Therapies in Medicine

journal homepage: www.elsevierhealth.com/journals/ctim

Medical yoga in the workplace setting−perceived stress and work

ability−a feasibility study
Iben Axén ∗ , Gabriella Follin
Unit of Intervention and Implementation Research for Worker Health, Institute of Environmental Medicine, Karolinska Institutet, Sweden

a r t i c l e i n f o a b s t r a c t

Article history: Objective: This study examined the feasibility of using an intervention of Medical Yoga in the workplace
Received 28 June 2016 and investigated its effects on perceived stress and work ability.
Received in revised form 28 October 2016 Design and setting: This was a quasi-experimental pilot study comparing a group who received Medical
Accepted 1 December 2016
Yoga (intervention group, N = 17), with a group waiting to receive Medical Yoga (control group, N = 15).
Available online 7 December 2016
Intervention: Medical Yoga in nine weekly sessions led by a certified instructor, as well as an instruction
film to be followed at home twice weekly.
Keywords:
Main outcome measures: Feasibility was assessed through recruitment, eligibility, willingness to par-
Yoga
Workplace ticipate, response to questionnaires and adherence to the intervention plan. Stress was measured with
Stress the Perceived Stress Scale, work ability with the Work Ability Index.
Work ability Results: Convincing unit managers to let their employees participate in this intervention was difficult.
Eligibility was perfect, but only 40% of workers were willing to participate. The subjects adhered to a great
extent to the intervention and answered the questionnaires satisfactorily. Reaching target individuals
requires careful attention to informing participants.
The intervention showed no significant effects on stress and work ability, though the two measures
correlated significantly over time.
Conclusion: Factors limiting feasibility of this workplace intervention were identified. Work place inter-
ventions may need to be sanctioned at a higher managerial level. The optimal time, length and availability
of the workplace intervention should be explored further. Knowledge from this study could be used as a
foundation when planning a larger scale study.
© 2016 Elsevier Ltd. All rights reserved.

1. Introduction concerns for patient safety,5 which leads to stress and ill-health
amongst staff.3 − more so in the public than the private domain6
In Sweden, as in the rest of the world, health care is a growing Work stress has been found to be associated with reduced work
sector in both the public and private arenas.1 Health care employs ability,7,8 i.e. reduced capacity to perform the tasks a function
a considerable number of people − half a million individuals in demands, and worker’s health and competence.9 Therefore, the
Sweden alone. This represents 13% of the workforce − the largest current situation in the health care sector is costly and could poten-
work contingent in the country − and the majority are women.2 In tially be a threat to safe medical management.
addition, the nursing and care professions have the highest num- Yoga is an ancient Tibetan form of health-promoting activity
bers of workers on sick leave.2 of all professional categories. that encompasses both the physical and the mental aspects of
There are reports from the health care sector of increased work- relaxation. It is a series of bodily movements combined with spe-
load, complex work processes, inability to perform the required cific breathing techniques and meditation, in which the focus of
work tasks within the allotted time, and a growing concern about attention is inwards, using the body as a tool to reach a medi-
achieving standards of quality3,4 Ultimately, this boils down to tative state. Its goals are health and well-being. The method has
been evaluated scientifically and has been shown to have pos-
itive effects on pain,10,11 stress.12,13 and quality of life12,14 In a
∗ Corresponding author at: Unit of Intervention and Implementation Research for study among nurses, yoga was found to improve sleep and decrease
Worker Health, Institute of Environmental Medicine, Karolinska Institutet. Nobels work stress.15 The measurable objective effects include lower blood
väg 13, 171 77 Stockholm, Sweden. pressure,14 reduced levels of stress hormones.16 and lower blood
E-mail addresses: Iben.axen@ki.se (I. Axén), gabriella.follin@stud.ki.se
(G. Follin).

http://dx.doi.org/10.1016/j.ctim.2016.12.001
0965-2299/© 2016 Elsevier Ltd. All rights reserved.

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 62 I. Axén, G. Follin / Complementary Therapies in Medicine 30 (2017) 61–66

glucose levels17,18 The type of yoga chosen seems indifferent for the local unit manager, one morning and one afternoon session −
the positive effects.19 each lasting 75 min − were scheduled every week in order to allow
Medical Yoga (MY) is a Swedish form of yoga adapted from the all staff to attend once a week. The sessions were timed so that
classic Kundalini yoga that allows people with neck and back pain to participants could attend after finishing a shift or on a day off. In
benefit from the exercises. Like traditional yoga, the movements in addition, the participants were instructed to practice MY at home at
MY are very slow, but they are always guided by an instructor who is least twice a week using a downloadable 25-min instruction video.
a trained health care practitioner. Studies of MY have demonstrated Due to a lack of suitable facilities at the workplace, the MY
positive effects on stress,12 and chronic low back pain20 and the training sessions were held at a nearby training facility. The lead
method is used in the Nordic countries, Australia, the UK and the investigator (GF), a certified MY instructor, was in charge of all the
US21 . sessions. The sessions − whose content is based on the MY protocol
The aim of this study, which is part of a master’s (MSc) study developed by the Institute of Medical Yoga25 − started with breath-
in occupational health, was to test the feasibility of a work-based ing exercises while lying down followed by seated exercises for the
intervention with MY among medical public nursing home and whole body, and finished with seated meditation. The frequency of
home care service staff. MY could, considering its stress-reducing the training was based on previous research26
effects be excellently suited for these types of health care work- The control group was offered MY after completion of the study
ers. The intervention was offered to the staff of one unit; the other period and was thus designated a waiting-list control group.
unit served as a control. The feasibility of this type of intervention
was determined through assessing recruitment, eligibility, willing- 2.4. Measurements and outcomes
ness to participate, response to questionnaires and adherence to
the intervention plan. Further, subjects’ stress levels and perceived Some demographic variables were collected for all participants:
work ability were assessed before and after the intervention and age, sex, profession, degree of employment (i.e. part or full time),
compared between the two groups. type of employment (i.e. permanent or temporary) and number of
years at the current work place.
The Perceived Stress Scale (PSS) was chosen because it is a
2. Materials and method
generic instrument that measures the perceived level of stress
in one’s life.27 It examines both work-related and private stress
2.1. Study design
through 14 questions that are summed up on a scale from 0 to 56;
the higher the value, the higher the levels of stress. A previous lon-
This was a quasi-experimental study, as the assignment to inter-
gitudinal study suggests that mean values for PSS range from 12.0
vention/control was not randomized.
to 17.5 among an adult population.28
The Work Ability Index (WAI) was used to measure perceived
2.2. Recruitment and sample work ability.29 It contains 7 items on work ability in relation to
the best perceived ability and in relation to work demands. It also
The unit managers of five work groups of medical staff in pub- involves parameters for illness and sick-listing. Guideline values
lic nursing homes and home care services in the target county in exist for excellent (44–49), good (37–43), moderate (28–36)and
southern Sweden were contacted to gauge their interest in the poor (7–27) work ability.30
study; three managers responded positively as regards their staff PSS and WAI were measured before the first training session
participating. Subsidiarity was the deciding factor for selecting and one week after ending the MY training for the intervention
participant workgroups; they had to be located close to the lead group, and at the corresponding times (i.e. nine weeks apart) for
investigator (GF), and the sample was therefore described as a con- the control group.
venience sample. The medical staff categories included registered To check compliance with the home training program, an auto-
nurses, auxiliary nurses and nurses’ assistants; the only inclusion mated text message was sent to the participants in the intervention
criterion was that the subjects belonged to any of these three pro- group every Sunday afternoon asking about the number of home
fessional categories. It was decided to exclude subjects who were training sessions during the past week. This task was managed
pregnant, as the pregnancy may lead to stress in itself,22,23 as well ®
using a program called SMS Track .31
as a decreased ability to deal with stress or reduced work ability.
Though these subjects were not prohibited from taking part in the 2.5. Data analysis
MY intervention, their data would be omitted from the analysis.
In the same vein, subjects who were currently undergoing other To assess the feasibility of the study, a number of parameters
forms of stress-reducing therapy would not be prohibited from the were examined. Recruitment rate was calculated through divid-
MY training, but their data would be excluded in the analysis. ing the number of units participating by the number of units
In the first step, the participating unit managers informed their approached. Eligibility was the number of participants excluded
staff about the study using a leaflet supplied by the investigators, by the initial stress question plus any of the exclusion criteria.
and invited staff to a meeting with the lead investigator. At the Willingness to participate was calculated through dividing the
meeting, information concerning MY, the purpose of the study number of subjects in the study by the number of subjects in the
and the logistics involved was provided, and questions from the source population. Response rate to questionnaires was the num-
potential participants were answered. Care was taken to keep the ber of those successfully completed divided by the total number
information regarding the potential effects of MY as neutral as pos- administered. Finally, adherence to the intervention was the num-
sible, only stating the outcome measures in the study and how they ber of exercise sessions performed (in class and at home) divided
would be measured. A screening question regarding stress.24 was by the “desired” number (9 supervised classes + 18 at-home exer-
answered by each of the staff members interested in participating. cises = 27). For those participants who trained more than 27 times,
adherence was noted as 27.
2.3. Intervention and setting Descriptive analysis compared the intervention and the control
group with regards to the available demographic variables using
The MY training was offered to the intervention group over a t-tests for parametric data and Mann-Whitney for non-parametric
period of nine weeks in the autumn of 2014. In agreement with data. Additionally, baseline values for PSS and WAI scores were

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 I. Axén, G. Follin / Complementary Therapies in Medicine 30 (2017) 61–66 63

compared between the intervention and control groups using t- actually more than requested). Mean adherence to the intervention
tests. was 21 sessions in total, giving 21/27 = 78%.
The change in PSS and WAI scores (from baseline to follow-
up) were then calculated and compared with t-tests between the 3.6. Sample characteristics
intervention and control groups. The association between the two
measurements was calculated both as a correlation coefficient The sample had a mean age of 51 years (SD 8.9) and included
(Spearman’s rank coefficient) and in a regression analysis. The only one man; the intervention group consisted of some registered
change in perceived work ability was the dependent variable, and nurses (26.7%) but no assistant nurses, whereas the control group
the change in perceived stress was the independent variable. The had no registered nurses and a relatively high proportion (38.5%) of
total number of exercise sessions was added as a covariate in the assistant nurses. There were no statistically significant differences
regression analysis. Data were analysed using SPSS, version 2232 . between the intervention and control groups regarding age, degree
or type of employment and number of years at the current work
2.6. Compliance with ethical standards place (results not shown); see Table 1 for details.

All participants were informed about the study verbally and 3.7. Stress and workability
in writing, and signed informed consent forms prior to participa-
tion. Ethical permission was granted by the ethics committee at Perceived stress was found to be equal between the two groups
Karolinska Institutet: 2014/1452-31/1. at baseline, and an improvement was noted in both groups over
the nine weeks to follow-up; no significant difference (p = 0.850) in
3. Results improvement between the groups was noted, however. Perceived
work ability was slightly different between the two groups at base-
A flow-chart can be found in Fig. 1 to explain the flow of partic- line. The intervention group scored 38.60, which is classified as
ipants through the study. good work ability, whereas the control group scored 36.42, which
is classified as moderate work ability. However, this difference was
not statistically significant (p = 0.766). During the nine weeks of
3.1. Recruitment
the study, both groups showed improvement in work ability. The
change score was not statistically significant between the groups
One of the three unit managers who had initially expressed an
(p = 0.404). The results are found in Table 2.
interest in the study declined to participate due to high workload,
A change in perceived stress was found to correlate significantly
suggesting that “the study result therefore would be biased”. Thus,
(p = 0.03) with a change in work ability (r = −0.582), normally con-
2 workgroups made up the final study sample, leaving the recruit-
sidered a moderate correlation.33 In the regression analysis, the
ment rate at 2/5, or 40%. The work group nearest to both the lead
association was found to be significant (B = −0.43, p = 0.003, CI:
investigator’s office and a training facility was chosen to be the
−0.69- −0.16). The total number of MY sessions was introduced as a
intervention group (60 employees) and the remaining group (21
covariate in the regression analysis, but did not generate significant
employees) thus became the control group.
effects (p = 0.141).

3.2. Eligibility
4. Discussion

According to the initial question regarding stress,24 there was

In this study, a workplace intervention with MY was tested
no risk of floor effect at baseline for either group. No subjects were
among health care professionals to determine the feasibility of the
excluded due to pregnancy or participation in other types of stress-
intervention, as well as the perceived stress and work ability of the
reducing treatment or activity; eligibility was thus perfect.
subjects. The major strength of this study was that it was prag-
matic; it was delivered in two public health care units in the same
3.3. Willingness to participate county in Sweden. The data collection took place in parallel for both
groups, rendering the effect of seasonal and organisational changes
In total, 32 participants registered for the study: 17 (28% of negligible. Restraints as regards research personnel, logistics and
target sample) in the intervention group and 15 (71% of target sam- time made it difficult to conduct a full-scale randomized study. The
ple) in the control group, which put willingness to participate at identified difficulties are nevertheless those experienced in real-life
32/81 = 40%. situations.

3.4. Response rates 4.1. Recruitment and sample

Two subjects were removed from each of the groups due to Recruiting participating work units and organizing the logistics
incomplete baseline questionnaires, producing a response rate to of the intervention proved to be challenging. It was noted, pri-
the initial questionnaires of 87.5%, and a total of 15/13 subjects in marily, that the unit managers approached were rather reluctant
the intervention/control groups respectively − 88% of the original to donate their employees’ time, which resulted in a convenience
sample. Furthermore, an additional two people in each group failed sample. Convenience samples are prone to selection bias, i.e. only
to complete the follow up-questionnaire, putting the response rate managers with an interest in their employees’ well-being or suf-
to the second questionnaires at 86%. ficient time to spare may have agreed to participate. The health
care unit with the supposed strongest need for stress reduction
3.5. Adherence to the intervention plan was too busy to participate. The intervention and control groups
differed in the composition of personnel, with many registered
Compliance with the MY training was quite varied, and ranged nurses and no assistant nurses in the intervention group, and no
from 2 sessions with the instructor plus 4 sessions at home (the registered nurses and many assistant nurses in the control group.
individual who trained the least) to 9 sessions with the instructor It is possible that due to the higher level of education in the inter-
plus 27 sessions at home (the individual who trained the most − vention group, these individuals may have had a lighter physical

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 64 I. Axén, G. Follin / Complementary Therapies in Medicine 30 (2017) 61–66

Fig. 1. The flow of participants in the study.

Table 1
Descriptive statistics of the sample at baseline.

Variable Total (n = 28) Intervention (n = 15) Control (n = 13)

Age, mean (SD) 51 (8.9) 54 (8.1) 47.5 (8.8)

Profession,
Registered nurse, proportion 14.3% 26.7% 0%
Auxiliary nurse, proportion 67.9% 73.3% 61.5%
Assistant nurse, proportion 17.9% 0% 38.5%
Years at the workplace, mean (SD) 14.6 (8.8) 14.2 (9.6) 15.0 (8.1)
Degree of full-time employment, mean (SD) 74.1% (12.8) 74.2% (16.6) 74.0% (7.6)
Type of employment
Permanent, proportion 100% (n = 15) 100% (n = 11)

Table 2
PSS and WAI mean scores and standard deviations (SD) in the intervention and control groups at baseline and follow-up, the changes between the measures, test of difference
between the groups and the confidence interval (CI) of the estimates.

Scores Group n Mean (SD) Test for differencesa

PSS Baseline Intervention 15 25.08 (7.207) p = 0.714 CI: −6.06 to 6.07

Control 13 25.08 (8.411)
WAI Baseline Intervention 15 38.60 (5.902) p = 0.766 CI: −2.65 to 7.01
Control 12 36.42 (6.244)
PSS Follow Up Intervention 13 17.62 (9.614) p = 0.374 CI: −7.51 to 6.24
Control 12 18.25 (6.566)
WAI Follow Up Intervention 13 39.17 (7.399) p = 0.262 CI: −5.22 to 5.55
Control 12 39.00 (5.360)
PSS change Intervention 13 −6.63 (6.413) p = 0.850 CI: −2.48 to 7.02
Control 12 −5.33 (5.614)
WAI change Intervention 13 −0.37 (5.093) p = 0.404 CI: −2. 32–5.34
Control 11 −1.18 (3.545)
a
= T-test of difference in means between groups before and after the intervention.

work load and could better manage their stress. It could be argued, 4.2. Eligibility and willingness to participate
however, that the nurses have higher stress than other personnel
due to greater responsibilities. As the groups were small, further The participation rate was rather low, despite obvious eligibility
subgroup analysis was deemed inappropriate. and room for stress reduction among the staff. It is a matter of con-
The use of a waiting-list control group may also be cern for future interventions that less than 40% of the work group
problematic.34 These participants had no interaction with the wanted to participate in an activity that was free and adapted to
instructor and did not invest any time or effort into reducing their their work schedule. The initial information about the intervention
stress levels. However, as there were no significant differences in was delivered by the unit managers, a method that may not be opti-
outcomes between the groups, the use of a waiting-list control mal and indeed could be perceived as a “top-down” approach. The
group seemed to serve its purpose in this study. intervention and control workgroups had different unit managers,

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 I. Axén, G. Follin / Complementary Therapies in Medicine 30 (2017) 61–66 65

which could affect the subjects’ willingness to participate, as well which may have prompted self-care strategies outside the control
as their stress levels and work ability. of the study. Further, many factors − both at the worksite and
Information from the rest of the staff concerning stress and work privately − may influence stress and work ability. No data were
ability was not collected, thus the general stress levels of the staff collected regarding work load, leadership, concomitant depression
are not known. It is possible that the intervention reached those or other medical conditions that may have confounded the results.
subjects in need of stress reduction, but it is also possible that the The significant correlation of perceived stress and work ability
staff that needed it the most were too busy to participate. is similar to that found in other studies.37,38 Thus, the association
found in previous cross-sectional studies was confirmed in this
4.3. Response rates prospective study.
In conclusion, knowledge from this study could be used as a
The response rate to questionnaires and adherence to the MY foundation when planning a larger scale study. The concerns raised
training among the people who participated was satisfactory. about unit managers not prioritizing stress management should
be explored further. A potential way forward could be qualitative
4.4. Adherence to the intervention plan interviews with the managers as well as the staff to investigate
the reasons for the low penetration. The intervention may pos-
Scrutinizing the intervention itself, scheduling the sessions at sibly need to be sanctioned from a higher organisational level.
the end of a working shift may have been perceived as stressful, Care should be taken when planning the intervention in terms
as the participants quickly had to get to the exercise facility. The of information, availability, site and time of MY sessions as well
intervention could possibly have been more successful if it took as the length of the intervention and an independent instructor.
place at the workplace itself. Adherence to the intervention varied When including subjects, information about health (like depres-
a great deal but the small sample makes further subgroup analysis sion, chronic pain conditions etc.) should be collected to facilitate
impossible. The instructor noted which participants attended each subgroup analysis. Additionally, the dilemma of measuring per-
supervised session. The number of home-exercises was measured ceived work ability in conjunction with an intervention that may
weekly with an SMS tool to avoid memory bias, but participants affect self-consciousness should be explored. To account for dif-
may still have over-reported their compliance. The number of opti- ferences between workgroups in workload, professions etc., a
mal weekly sessions was based on previous research,26 but it may randomized trial would be desirable.
be speculated that the length of the intervention was too short for
the full effects of MY to take place.35 The fact that the MY instruc- Conflicts of interest
tor and the research assistant were the same person may have
led to acquiescence bias, thus rendering self-rated measures con- None.
cerning perceived stress, workability and compliance with exercise
uncertain.
Author’s contributions

4.5. Stress and workability

Both authors were involved in the design and analysis, and the
presentation of data.
A strength of the study was the use of validated instruments to
measure stress and perceived work ability. The PSS was chosen as
Acknowledgements
both work-related and private stress was thought to be relevant,
and the baseline values suggest that a stress-reducing interven-
We would like to thank the workers who participated in the
tion was indeed warranted. During the nine weeks of the study,
study, as well as their managers who agreed to be part of this study.
perceived stress diminished and perceived work ability increased
both in the intervention and the control groups. There were no sta-
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