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The authors wish to thank the all the staff from the AAMI Insurance Company who participated
in and assisted with the study. We also thank Ian Gale, Julie Gale-Ball, Adam Elkman, Rosa Galante,
and Emra Oguzkaya for their valuable assistance during the project.
Requests for reprints should be sent to Gerard A. Kennedy at Gerard.Kennedy@vu.edu.au.
Australian Journal of Clinical and Experimental Hypnosis
Vol. 35, No. 2, 2007, 169–193
POWER BREAK: A BRIEF HYPNORELAXATION
PROGRAM TO REDUCE WORK-RELATED FATIGUE AND
IMPROVE WORK SATISFACTION, PRODUCTIVITY,
AND WELL-BEING
Gerard A. Kennedy
Victoria University
Harry Ball
Medident Sleep Clinic
The aim of this study was to examine the effect of hypnorelaxation “power breaks”
taken each day over a four-week period on fatigue, mood, physical health symptoms and
satisfaction with work. The participants were 75 men and women who were employees
at AAMI Insurance Company telephone call centres in Melbourne, Australia. It was
hypothesised that four weeks of practising the Power Break Program (hypnosis) for two
10-minute sessions each day would significantly reduce fatigue symptoms and improve
mood, physical health and satisfaction with work. The results showed that the Power
Break Program significantly reduced fatigue, negative mood and physical symptoms, and
improved satisfaction with work. The Power Break Program consisted of an effective, but
minimal intervention that could easily be adapted to any workplace. The Power Break
Program appeared to meet the psychological needs of many of the participants and it
was effective in delivering a positive outcome to participants.
The terms sleepiness and fatigue are often used interchangeably, but a
distinction should be made between the two states. It is possible to be
sleepy without being fatigued, fatigued without being sleepy, both sleepy
and fatigued, or neither. When people go to bed they may be sleepy and/or
fatigued. However, on many nights when people go to bed at their scheduled
bedtime they are neither sleepy nor fatigued, yet they fall asleep quickly. The
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170 Kennedy and Ball
reason they fall asleep is that their scheduled bedtime falls during a time of
day when there is a natural maximum propensity to sleep and they have
also become conditioned to sleep at that time of day. Humans have two
periods each day during which the propensity to sleep is high (Aschoff, 1994;
Campbell, Dawson, & Zulley, 1993). The longest sleep episode (6–9 hours)
usually occurs at night, while the second shorter period occurs during the day
(post-lunch dip) (Campbell et al., 1993).
Taking brief “power naps” has been widely advocated as a way
of decreasing fatigue and sleepiness, particularly in situations where
performance and vigilance must be sustained for long periods of time
and when sleep deprivation may also be present (Bonnet & Arand, 1995;
Gillberg, Kecklund, Axelsson, & Akerstedt, 1996; Haslam, 1985; Lumley,
Roehrs, Zorick, Lamphere, & Roth, 1986; Naitoh, Kelly, & Babkoff, 1992;
Reyner & Horne, 1997; Takahashi & Arito, 2000). Following a night of
restricted sleep, a daytime nap of between 15 and 120 minutes has been
shown to reduce subjectively and objectively measured sleepiness in day
workers (Gillberg et al,, 1996) and narcoleptic, and alert and sleep-deprived
day workers (Helmus et al., 1997). Brief naps have also been shown to
decrease fatigue and improve performance and vigilance (Dinges, Orne, &
Orne, 1985). Horne and Reyner (1996) demonstrated that sleepiness and
“accidents” on a driving simulator were reduced following a 15-minute nap.
A number of studies (Gillberg, 1984; Matsumoto, & Harada, 1994; Sallinen,
Harma, Akerstedt, Rosa, & Lillqvist, 1998) have shown that a nap during the
night reduces the effects of fatigue. However, conflicting results have been
reported in studies assessing the benefits of naps taken prior to a night shift
(Bonnet, 1991; Bonnet & Arand, 1995; Harma, Knauth, & Ilmarinen, 1989;
Naitoh, Englund, & Ryman, 1982; Rosa, 1993). Therefore, the timing of
naps within the circadian day may be of particular importance.
Short power naps (e.g., 15–20 minutes) have been shown to be more
efficacious than longer naps because the sleeper does not usually enter
slow-wave sleep and therefore experiences minimal sleep inertia upon
awakening (Dinges et al., 1985). The symptoms of sleep inertia, although
usually only present briefly, include disorientation and grogginess (Jewett
et al., 1999). Power naps should not the thought of as a replacement
for normal sleep and should only be used within a day as a means of
temporarily attenuating fatigue and/or sleepiness.
Taking a nap at times other than when sleep propensity is high (night-
time and mid-afternoon), can be difficult even if fatigue and/or sleepiness
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Power Break 171
are present. This is because it is much more difficult to fall asleep at times
outside the natural circadian rhythm of sleep propensity (Campbell et
al., 1993). There are a number of occupations where power naps may be
useful and may even need to be mandated. These occupations include
those where rotational shift work is involved or there is no real schedule
(e.g., long-distance truck driving). There are a number of aspects associated
with napping that make it difficult or undesirable to promote during day
shifts. These include the following: (a) people find it difficult to fall asleep
during napping opportunities (Campbell et al., 1993); (b) special napping
facilities may be required; (c) people may sleep for too long; (d) long naps
and even short naps may be associated with significant sleep inertia (Jewett
et al., 1999); and (e) many employers and employees have a negative view
of sleeping in the workplace during the day.
Fatigue is a more common problem at work during the day than sleepiness.
Therefore, the scheduling of appropriate breaks during day shift work may
be more useful than advocating power naps. Most office-based work requires
the prolonged use of computers and/or other communication technologies
such as telephones. Many workers become fatigued after continuous periods
of using a computer or telephone. The normal work breaks (morning and
afternoon tea and lunch time) are useful, but may not necessarily allow
workers to reduce mental and/or physical fatigue. During the typical work
break, workers often perform other personal tasks such as making telephone
calls, banking and paying bills, re-parking cars and topping-up parking meters,
or discussing work with colleagues. It is also common for people to work
through scheduled breaks due to the pressures of modern business. The
practice of working through breaks and doing personal tasks during breaks
may further contribute to work-related fatigue. When this is coupled with the
normal stresses related to home-life and other health factors such as inactivity,
poor diet and poor sleep habits, it becomes evident that fatigue may become
one of the major health issues in the next several decades.
It is clear that workers need to take breaks to be revitalised during the day
in order to continue performing well. However, it is not likely that power
naps will become widely used in the business world in Australia or in other
countries where the work ethic is perceived to be in conflict with resting in
the workplace. This is largely due to negative attitudes that both employees
and employers have about sleeping during the day in the workplace and
also the difficulty of accommodating sleeping workers in the workplace. In
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172 Kennedy and Ball
addition, research has shown that sleeping during the day for a brief period of
time is difficult due to both biological (circadian rhythm of sleep propensity)
and environmental (e.g., noise and light levels) factors (Akerstedt, 1988).
A growing number of studies have shown that many people report feeling
refreshed and revitalised following short sessions of various types of relaxation,
hypnosis, or meditation. Many studies show that hypnosis, relaxation, and
guided imagery have significant positive effects on psychological and physical
wellness (for review, see Gruzelier, 2002). Gruzelier (2002) provides evidence
from studies reviewed that interventions based around short daily sessions
of hypnosis, relaxation, or guided imagery improve the immune response
and enhance mood and well-being in subjects with a variety of conditions.
Similarly, there have been many studies of various types of meditation,
particularly transcendental meditation, which suggest that it has a powerful
effect on physical and mental well-being (for reviews see Bogart, 1991; Canter
& Ernst, 2003; Smith, Richardson, Hoffman, & Pilkington, 2005).
More recently, studies have reported that the practice of mindfulness (a
meditational technique “loosely” derived from Buddhism) has some benefits in
assisting people with a number of psychological and physical conditions ranging
from anger to various cancers (for a conceptual and empirical review, see
Baer, 2003). A meta-analysis of mindfulness-based interventions by Grossman,
Niemann, Schmidt, and Walach (2004) showed that only 20 of 64 studies
retrieved met the statistical criteria for inclusion. Mindfulness studies were
excluded because they did not meet the following criteria: (a) insufficient detail
about the interventions; (b) poor quality of health intervention; (c) inadequate
statistical analysis; (d) mindfulness was not the central component of intervention;
or (e) setting of the intervention or sample deviated too widely from the health-
related mindfulness program. Nevertheless, Grossman et al. (2004) concluded
that mindfulness-based interventions were useful in helping a broad range of
individuals cope with both clinical and non-clinical problems.
The reviews cited above highlight problems facing many clinicians in
reporting information about relaxation-, hypnosis- and meditation-based
interventions. For clinicians, the main goal is to assist patients towards better
wellness and thoughts about statistical research design, for practical reasons, are
usually given a lower priority. However, clinicians’ reports of single cases or
small studies, with less than optimal statistical control, may provide useful and
heuristically valuable information.
Studies have shown that following brief sessions of relaxation, hypnosis,
or meditation, many subjects report increased feelings of mental and physical
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Power Break 173
well-being (Baer, 2003; Grossman et al., 2004). Given the problems outlined
above with taking power naps during the day in the workplace, it may be more
realistic to promote “power breaks” (brief periods of relaxation, hypnosis, or
meditation) during the working day. The aim of the study reported here was
to determine the effect of two 10-minute Power Breaks taken each day over a
four-week period on fatigue, mood, physical health symptoms, and satisfaction
with work. It was hypothesised that practising the Power Break Program, for
two 10-minute sessions each day over four weeks, would significantly reduce
fatigue and improve mood, physical health, and satisfaction with work.
METHOD
Participants
The participants were 75 men and women who were employees at AAMI
Insurance Company telephone call centres in Melbourne, Australia. One
hundred and twenty employees were approached and 75 (62.5%) volunteered
for either the experimental group (Power Break™ group) or the control group
(there was no participant attrition during the study). Thus, assignment to the two
groups was not random and this issue is addressed in the next section. The Power
Break™ group consisted of 18 men and 25 women (n = 43). The mean age for
men in the Power Break™ group was 27.88 years (SD = 6.59) and for women
it was 29.64 years (SD = 10.47). The control group consisted of 14 men and 18
women (n = 32). The mean age for men in this group was 33.64 years (SD =
8.60) and for women it was 28.44 years (SD = 9.43).
The assignment of participants to the groups in the study was not ideal.
The employer requested that workers be allowed to select which group they
wanted to participate in. The rationale of the employer was that this would
reflect a more realistic situation if power breaks were to be instituted in the
workplace at some later date. The split-plot analysis of variance overcomes
the participant selection issue, because it compares the groups before the
study period and after the study period, and most importantly it compares
whether change over the study period (pre to post) is the same or different
within each group. The issue of expectation effects that may have arisen due to
self-selection into the Power Break™ group could not be avoided. However,
this problem is usually encountered in most studies of non-drug therapeutic
intervention, because it is difficult to “blind” subjects to the treatment. Given
the minimal nature of the Power Break™ intervention, it would be surprising
if expectations were maintained over the entire 20-day intervention period.
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174 Kennedy and Ball
Measures
Independent Variables
1. Power Break™ — The program consisted of a 10-minute relaxation script
recorded on a compact disk that participants were required to listen to, via
headphones attached to a computer work station, on two occasions each day.
The script included suggestions for relaxation and statements about being
re-energised, recorded against a background of music composed specifically
for this project. (This script was published in the May 2007 edition of the
AJCEH.) The Power Break™ Program was designed to allow people to take
a short break in the workplace to facilitate relaxation, reduce stress, promote
feelings of being re-energised, and thus perform more efficiently upon
returning to work. Power Break™ was specifically designed as a short break
of only 10 minutes in order to minimise the chance of people falling asleep
during the break. Power Break™ was not meant to be a power nap. With the
short period of a Power Break™, it was unlikely that people would fall asleep,
unless they were extremely efficient sleepers, sleep deprived, or had a sleep
disorder (e.g., obstructive sleep apnoea, or narcolepsy).
Dependent Variables
1. Physical Health — The Symptoms Checklist was developed by Dunnell and
Cartwright (1972) and consists of 31 commonly reported physical symptoms.
The symptoms cover all major bodily systems, including the cardiovascular,
respiratory, gastrointestinal, neurological, and musculoskeletal. In reference to
the reliability and validity of symptoms checklists, Watson and Pennebaker
(1989) reported that health complaint measures correlate about as highly with
mood disturbance as they do with each other.
2. Mood — Profile of Mood States 37-item short version was developed from
the original questionnaire that consisted of 65 statements. Statements include
both negative and positive emotions (e.g., cheerful and sad). Six subscale scores:
tension/anxiety, depression/dejection, anger/hostility, vigour/activity, fatigue/
inertia and confusion/bewilderment, and a total mood disturbance score can
be obtained from the Profile of Mood States. The reliability and validity of
the scale(s) has been well established and normative data are available (McNair,
Lorr, & Droppleman, 1981). The 37-item short version shows similar levels
of reliability and validity to those of the original 65-item version (Shacham,
1983).
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Power Break 175
3. Job Satisfaction — The Abridged Job Description Index was developed
from the original Job Description Index (Smith, Kendall, & Hulin, 1969).
The Abridged Job Descriptive Index (AJDI) described by Russell et al. (2004)
includes 25 items that measure satisfaction with job, present pay, promotion
opportunities, supervision, and people at work.
4. Satisfaction with the Power Break™ Program — a 5-point, single item,
Likert scale ranging from Strongly disagree to Strongly agree was used to
measure satisfaction with the Power Break™ Program.
5. Compliance with the Power Break™ Program was measured by requesting
participants to complete a daily log for the 20-day period of the study.
6. Would you like to continue using a Power Break™ during work? — a 5-point,
single item Likert scale ranging from Strongly disagree to Strongly agree was
used to measure interest in continuing the program in the workplace.
7. Subjective Comments about the Power Break™ Program — Participants were
requested to write comments about what they thought of the Power Break™
Program.
Procedure
During week one, participants in the Power Break™ and control groups
were requested to complete the set of questionnaires described above. In
week two, 43 participants (Power Break™ group) commenced the Power
Break™ Program of two 10-minute sessions per day, the first session after
25% of the work shift had been completed and the second session after
75% of the work shift had been completed, for four weeks. During the two
10-minute breaks, the Power Break™ group were seated upright at standard
computer/telephone work stations in a section of a large open style office
area where they usually worked. This area was not screened off and was
essentially not different from other areas of the office. Following the Power
Break™, participants had five minutes during which they were free to take
a shorter than usual tea break before returning to their work stations in the
same office area. During this time, participants typically drank tea, coffee or
other beverages and a few quickly went outside to smoke a cigarette. The
control group of 32 participants was yoked to the Power Break™ group and
took their normal 15-minute work breaks at the same time during this same
four-week period. During this time, control participants typically drank tea,
coffee or other beverages, chatted or went outside to smoke a cigarette. At the
end of this four-week period, in week six, all participants again completed the
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176 Kennedy and Ball
set of questionnaires. Participants’ compliance with the two Power Breaks per
day was encouraged via daily reminders from the site managers and by being
required to complete a daily log of Power Breaks. See Table 1 for the design
of the study.
Table 1: Study Design
Groups Week 1 Weeks 2-5 Week 6
Experimental group Questionnaire 10 min. Power Break + 5 min. Questionnaire
n = 43 battery tea break x 2 per day battery
Control group Questionnaire Normal 15 min. tea break Questionnaire
n = 32 battery x 2 per day yoked to battery
Power Break group
RESULTS
Data Analysis
Data were analysed using the Statistical Package for the Social Sciences (SPSS
Version 14.0). One-way analysis of variance was utilised to test whether there
were any statistical differences in age and gender between the Power Break
and control groups. Pearson’s Chi-square analyses were used to determine
whether there were any statistical differences between the Power Break and
control groups, with respect to previous occupation and level of education.
Compliance with the Power Break program was assessed by analysing the
logs of adherence to the program completed by participants and responses to
a 5-point scale rating compliance. Satisfaction with, and whether participants
would like to continue doing the Power Break program, were measured
on 5-point rating scales (Figs 1 and 2). All other dependent variables were
analysed using the SPSS Split-Plot Analyses of Variance (SPANOVA)
procedure. SPANOVA is appropriate for mixed research designs that employ
independent groups with repeated measures. The between-subjects factor was
group (Power Break versus control) and the within-subjects factor was time
(pre- and post- the study period). The statistical significance level was set at p
< .01 for all comparisons.
Participant Characteristics
There were no statistical age differences between the Power Break and control
groups, F(1) = 1.11, p = .29 η2 = .01, or between the number of men and
women within the groups, F(1) = .63, p = .42, η2 = .009. There were no statistical
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Power Break 177
differences between the Power Break or control groups for previous occupation,
χ(4) = 2.47, p = .64, or for level of education, χ(4) = 5.93, p = .20.
Compliance With the Power Break Program
Thirty-eight of the 43 participants in the Power Break group completed
compliance logs during the four-week trial. The maximum possible level of
compliance (100%) consisted of completing the Power Break 40 times (2
times per day x 20 days). The mean compliance level for the 38 subjects who
completed the log was M = 31.87 days (SD = 4.10), or in percentage terms
79.68% compliance.
Satisfaction With the Power Break Program
Participants were also requested to rate satisfaction with the Power Break
Program on a 5-point, single-item Likert scale varying from Strongly disagree
to Strongly agree (Fig. 1). Figure 1 shows that 11.6% were not sure Power
Break was useful, while the majority rated it as either moderately (25.6%) or
strongly (55.8%) useful.
Would You Like to Continue Using a Power Break During Work?
Participants were also requested to rate whether they would like to continue
doing the Power Break Program on a 5-point, single-item Likert scale varying
from Strongly disagree to Strongly agree (Fig. 2). Figure 2 shows that the
majority rated either moderately (27.9%) or strongly (58.1%) that they would
like to continue doing the Power Break Program.
Physical Health Symptoms
Table 2 shows that were no significant effects for group, or time, but the
interaction effect between group and time was significant. Figure 3 shows
that symptom total scores decreased significantly in the Power Break group
(p < .01), but did not change in the control group (p > .01) across the study
period.
Mood States
For depression/dejection, tension/anxiety, anger/hostility and fatigue/inertia,
Table 2 shows that there were no significant effects for group or time, but
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178 Kennedy and Ball
that the interaction effects between group and time were significant. Figure
4 demonstrates that depression/dejection scores decreased significantly in the
Power Break group (p < .01) and increased significantly in the control group
(p < .01) across the study period. Figure 5 outlines that tension/anxiety scores
decreased significantly in the Power Break group (p < .01) and increased, but
not significantly in the control group (p > .01) across the study period. Figure
6 shows that the anger/hostility scores for the Power Break group decreased
significantly (p < .01), while scores for the control group did not change
significantly (p > .01) across the study period. Figure 7 also depicts that anger/
hostility scores decreased significantly in the Power Break group (p < .01) and
increased, but not significantly, in the control group (p > .01) across the study
period.
For confusion/bewilderment, Table 2 indicates that the main effect for
group was not significant, but that the main effect for time and the interaction
effect between group and time were significant. Figure 8 shows that confusion/
bewilderment scores decreased significantly in the Power Break group (p <
.01), while scores for the control group did not change significantly (p > .01)
across the study period.
Table 2 indicates that for vigour/activity there were no significant effects
for group, or time, and that the interaction effect between group and time was
not significant. Figure 9 shows that the vigour/activity scores for the Power
Break and control groups increased only slightly across the study period.
Table 2 indicates that for total mood disturbance, there were no significant
main effects for group or time, but that the interaction effect between
group and time was statistically significant. Figure 10 shows that total mood
disturbance scores decreased significantly in the Power Break group (p < .01),
while scores for the control group did not change significantly (p > .01) across
the study period.
Abridged Job Description Index
Table 3 highlights that for satisfaction with job, the effects for group or
interaction were not significant, but the effect for time was significant. Figure
11 also shows satisfaction with job scores increased significantly for the Power
Break group (p < .01), but did not change significantly for the control group
(p > .01) across the study period. For satisfaction with present pay, Table 3
indicates there was a significant effect for group, but that the effect time and
the effect for the interaction effect between group and time were significant.
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Power Break 179
Table 2: The Results of the Split-Plot Analysis of Variance for Physical Health Symptoms
and Mood Variables
Var iables Effect F df p η2
Physical health symptoms Group 2.48 1, 56 .12 .04
Time 1.54 1, 56 .22 .03
Group x Time 8.50 1, 56 .005 .13
Depression/dejection Group 2.54 1, 68 .12 .35
Time 0.30 1, 68 .59 .004
Group x Time 6.42 1, 68 .01 .09
Tension/anxiety Group 1.17 1, 70 .28 .02
Time 1.31 1, 70 .26 .02
Group x Time 9.69 1, 70 .003 .12
Anger/hostility Group 3.90 1, 70 .04 .04
Time 1.70 1, 70 .19 .02
Group x Time 8.07 1, 70 .006 .10
Fatigue/inertia Group 1.06 1, 69 .31 .02
Time 3.55 1, 69 .06 .05
Group x Time 8.15 1, 69 .006 .11
Confusion/bewilderment Group 0.24 1, 69 .62 .004
Time 6.81 1, 69 .01 .90
Group x Time 14.48 1, 69 .0005 .17
Vigour/activity Group 0.47 1, 68 .49 .007
Time 1.74 1, 69 .19 .02
Group x Time 0.55 1, 69 .46 .008
Total mood disturbance Group 1.65 1, 66 .20 .02
Time 3.41 1, 66 .06 .05
Group x Time 13.54 1, 66 .0005 .17
Figure 12 shows that scores for present pay satisfaction for the Power Break
group increased significantly (p < .01), while those for the control group did
not change significantly (p > .01) across the study period. For satisfaction with
promotion opportunities and with people at work,Table 3 indicates that there
were no significant main effects for group or time, and that the interaction
effects between group and time were not significant (see Figs 13 and 15). Table
3 shows that for satisfaction with supervision there was a significant effect
for group, but not for time, and that the interaction effect between group
and time and group was not significant. Figure 14 delineates that scores for
satisfaction with supervision were significantly (p < .01) higher for the Power
Break group, in comparison to the control group, both pre- and post- the
study period.
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180 Kennedy and Ball
Table 3: The Results of the Split-Plot Analysis of Variance for the Abridged Job
Description Index Variables
Variables Effect F df p η2
Satisfaction with job Group 2.64 1, 60 .11 .04
Time 6.66 1, 60 .01 .10
Group x Time 5.27 1, 60 .02 .08
Satisfaction with present pay Group 7.45 1, 60 .008 .12
Time 1.08 1, 60 .30 .02
Group x Time 4.20 1, 60 .04 .07
Satisfaction with promotion Group 0.14 1, 57 .70 .002
Time 0.09 1, 57 .76 .002
Group x Time 0.29 1, 57 .59 .005
Satisfaction with supervision Group 7.56 1, 61 .008 .11
Time 0.69 1, 61 .41 .01
Group x Time 0.08 1, 61 .78 .001
Satisfaction with people Group 0.47 1, 62 .49 .008
Time 0.60 1, 62 .44 .01
Group x Time 0.01 1, 62 .92 .00
Subjective Reports About the Power Break Program
Participants were also requested to supply subjective comments about what
they thought about the Power Break Program. Participants’ subjective
comments were analysed for the number of embedded positive or negative
comments. There were 107 positive comment and 29 negative comments.
Positive comments outnumbered negative comments by about 3.69 to 1. In
most cases, the negative comments were suggestions about how the program
might be improved (e.g., see negative comments). These data were analysed
by applying a qualitative procedure to extract the dominant themes that were
expressed by participants.
The following are examples of positive comments:
I really enjoyed the Power Break. I found I was able to cope with increased caller/
calls better and not get as stressed. I found myself relaxed throughout the day and I
think I slept better. I noticed now that it’s finished I’m a little more tense especially
around the shoulders and people are bugging me a little more. I would like to keep
doing this if at all possible. (Participant 14)
I loved the Power Break experience! I did find that my memory, focus and
confidence were all vastly improved and have since remained at a much higher
level. I feel better equipped to assist and respond to customers, more confident
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in my ability to solve problems and desire a much higher level of satisfaction
from my work. Thank you so much for allowing me to participate in this study.
I would recommend the practice be installed as a permanent element of the job.
(Participant 19)
The benefits were: Less agitated with customers; more relaxed easygoing which
gave better service; could better approach customers; a lot happier for some reason
at work and looked forward to the Power Break and felt more positive after I had
done it; I was less rushed in my conversations with customers and listened to the
customers needs; I was more relaxed with fellow colleagues and enjoyed my work
a whole lot more; it was good to learn to relax more even if it was only 15 mins —
the two/three hours after was more relaxed as well. (Participant 29)
The Power Break program was great. It helped me be more patient at work, but also
I was having a bit of health and personal problem in my life during those four weeks.
The Power Break helped me through these difficult times by looking at more positive
aspects and take each day as it comes with a good smile. Thank you for letting me
experience that as it had bought me a lot of positive in my life. (Participant 30)
The following are examples of negative comments:
At the start it was interesting and exciting, but listening to the same thing made it a bit
boring and I started to feel that I knew the program off by heart. (Participant 4)
The only improvement would be if it were possible to have the computer set up in a
more private area to make it easier to relax and not be interrupted. (Participant 8)
I felt that after the breaks I would come back tired as it made me want to sleep.
(Participant 10)
Was a little repetitive and it got a bit too much after the 3rd week. It’ll be good if
we can change the CD after each week. (Participant 16)
I found that the man’s voice got annoying after a while. A woman’s voice would’ve
been much better. (Participant 32)
The dominant theme that was distilled from their overall comments was
that the majority of subjects found that the Power Break Program was highly
beneficial and that they would like to continue doing something like this
either at work and/or at home. With respect to the negative comments, the
main themes were centred on the aspects of the program being repetitive,
boring or qualitatively not to the liking of the participant (e.g., see above).
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182 Kennedy and Ball
Figure 1: Percent of Participants in the Power Break Group (n = 43) by Ratings of Power
Break Program Was Useful
Figure 2: Percent of Participants in the Power Break Group (n = 43) by Ratings of Like
to Continue Power Break Program
DISCUSSION
The aim of this study was to determine the effect of two 10-minute Power
Breaks per day over a four-week period on fatigue, mood, physical health
symptoms, and satisfaction with work. It was hypothesised that four weeks
of practising the Power Break Program for two 10-minute sessions each
day would reduce fatigue and would improve mood, physical health, and
satisfaction with work.
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Power Break 183
Figure 3: Means and Standard Errors for Symptoms Total for Power
Break (n = 43) and Control Groups (n = 32) Pre- and
Post- Study
Figure 4: Means and Standard Errors for Depression/Dejection for
Power Break (n = 43) and Control (n = 32) Groups Pre-
and Post- Study
Figure 5: Means and Standard Errors for Tension/Anxiety for Power
Break (n = 43) and Control (n = 32) Groups Pre- and Post-
Study
Figure 6: Means and Standard Errors for Anger/Hostility for Power
Break (n = 43) and Control (n = 32) Groups Pre- and
Post- Study
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184 Kennedy and Ball
Figure 7: Means and Standard Errors for Fatigue/Inertia for Power
Break (n = 43) and Control (n = 32) Groups Pre- and
Post- Study
Figure 8: Means and Standard Errors for Confusion/Bewilderment
for Power Break (n = 43) and Control (n = 32) Groups
Pre- and Post- Study
Figure 9: Means and Standard Errors for Vigour/Activity for Power
Break (n = 43) and Control (n = 32) Groups Pre- and Post-
Study
Figure 10: Means and Standard Errors for Total Mood Disturbance
for Power Break (n = 43) and Control (n = 32) Groups
Pre- and Post- Study
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Power Break 185
Figure 11: Means and Standard Errors for Satisfaction With Job for
Power Break (n = 43) and Control (n = 32) Groups Pre-
and Post- Study
Figure 12: Means and Standard Errors for Satisfaction With Present
Pay for Power Break and Control Groups Pre- and Post-
Study
Figure 13: Means and Standard Errors for Satisfaction With
Promotion Opportunities for Power Break and Control
Groups Pre- and Post- Study
Figure 14: Means and Standard Errors for Satisfaction With
Supervision for Power Break (n = 43) and Control (n =
32) Groups Pre- and Post- Study
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186 Kennedy and Ball
Figure 15: Means and Standard Errors for Satisfaction With People at Work for Power
Break (n = 43) and Control (n = 32) Groups Pre- and Post- Study
Mood and Physical Health Symptoms
The findings of the study partly supported the hypothesis that the
Power Break Program would reduce self-reported fatigue and negative
mood. Self-reported scores for depression/dejection, tension/anxiety, anger/
hostility, fatigue/inertia, confusion/bewilderment, and total mood disturbance
decreased significantly in the Power Break group, but not in the control group
across the study period. There were no real differences reported in terms of
positive scale vigour. Vigour scores for both the Power Break and control
groups increased slightly across the study period. Similarly, the findings of the
study also supported the hypothesis that the Power Break Program would
improve self-reported physical health. Participants in the Power Break group
showed a significant reduction in reported negative physical symptoms, while
participants in the control group showed no change in the mean number of
reported symptoms across the study period.
Participants in the Power Break group reported higher scores on each of
the negative mood scales and higher levels of physical health symptoms at
the beginning of the study in comparison to the control group participants.
However, these differences were not large as none of the effects for group in the
split-plot ANOVAs were statistically significant. The slightly higher scores may
have been due to the fact that participants were allowed to volunteer for either
the Power Break or control groups. Given that subjects were not randomly
assigned to each group, due to the constraints requested by the employer and
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Power Break 187
difficulties associated with conducting the study in the actual workplace, it
may be that participants who elected to be in the Power Break group did so
because they had a higher level of psychological need. Evidence for the idea
that psychological need probably led some participants to volunteer for the
Power Break and not the control group can be seen in some of the subjective
verbal feedback reports made by participants in the Power Break group. The
following example illustrates this:
The Power Break program was great. It helped me be more patient at work, but
also I was having a bit of health and personal problem in my life during those four
weeks. The Power Break helped me through these difficult times by looking at
more positive aspects and take each day as it comes with a good smile. Thank you
for letting me experience that as it had bought me a lot of positive in my life.
Further evidence supporting this idea can also be seen in the attributions
that other participants made in their feedback about the Power Break Program.
This idea is also supported by examining the Power Break script, which
shows that the nature of the intervention was relatively minimal in terms of
suggestions for improved wellness. However, at the same time this attests to the
fact there was a psychological need and that it can be met by interventions like
the Power Break Program that are relatively simple and cost effective.
Self-selection to the experimental and control groups was a limitation of
the study and although the results showed that by the end of the study period
the Power Break group reported lower negative mood and physical symptoms
scores that were equivalent to levels shown by control participants, the findings
need to be regarded with caution. However, the design of the study did
allow the issue of participant self-selection to the Power Break group to be
overcome by comparing the relative change in the two groups over time using
the split-plot ANOVA procedure. In addition, participants in the Power Break
and control groups did not differ with respect to age, gender, educational level
or previous employment characteristics.
The finding that the brief Power Breaks, undertaken two times each day
over the 20 days of the study reduced self-reported fatigue, negative mood,
and physical symptoms supports the findings of many of the studies that
were examined in the reviews by Baer (2003) and Grossman et al. (2004).
These studies showed that brief sessions of relaxation, hypnosis, meditation or
combinations of these approaches led to subjects reporting reduced feelings of
fatigue and increased feelings of mental and physical well-being. The effects
of reduced fatigue and increased feeling of physical and mental well-being
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188 Kennedy and Ball
achieved by brief periods of relaxation or meditation in the workplace similar
to the Power Break Program employed in the present study appear to be
similar to the effects reported after brief power naps (e.g., Bonnet & Arand,
1995; Gillberg et al., 1996; Haslam, 1985; Lumley et al., 1986; Naitoh et al.,
1992; Reyner & Horne, 1997; Takahashi & Arito, 2000).
There is no evidence that relaxation breaks, such as those in the Power
Break Program, can reduce sleepiness and/or symptoms of sleepiness.
However, fatigue is a more common problem at work during the day than
sleepiness. The scheduling of appropriate breaks during day shift work may be
more useful than advocating power naps.
Satisfaction With Work
The hypothesis that the Power Break Program would significantly improve
work satisfaction was partly supported. It was found that satisfaction with
job scores increased significantly for the Power Break group, but did not
change for the control group across the study period. Scores for present pay
satisfaction were significantly lower in the Power Break group in comparison
to the control group, at the beginning of the study period, but increased
significantly across the study period to equal those of the control group. Scores
for satisfaction with supervision were higher for the Power Break group in
comparison to the control group, both before and after the study period. There
were no significant differences between the Power Break and control groups,
before or after the study period, for satisfaction with promotion opportunities
and satisfaction with people at work scores. Many of the statements made
in the qualitative feedback about the Power Break Program indicated that it
improved both satisfaction with work, attitudes to work, and work efficiency
The following examples illustrate this:
With Power Break it was nice to relax, take time off the phone. I was more alert
and happy to take a call.
It was pretty good. I thought it had a positive effect on my work and performance.
I found that during the study my body was actually looking forward to having the
break. If I missed a break or was late, I found great relief when finally getting around
to having the break. Upon returning to work after the break, I felt more able to
carry on with my work than if I didn’t have the break. I was more clear minded
and more alert even if I’d had less sleep the night before. Overall, I found it very
advantageous and was disappointed when the 4 weeks was up. It is something I’ve
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Power Break 189
started to include in my private life and will continue to do so. I’ve found that these
2, 15 min. breaks are really helpful and have helped me physically and mentally here
at work and at home.
Power Break was a great program. I looked forward to sessions and knew I would
feel revived after and enjoy my work more. I miss having a Power Break each
day and would strongly recommend they become available for staff in stressful
environments, such as call centres.
It was a great stress relief having even just a small time off the phones gave me a little
more motivation. Overall I did see a difference in my attitude towards my work.
A major beneficial factor of having the ability to have a Power Break more so was
to re-focus on the days targets and objectives.
In the last four weeks, I have discovered that I’m actually more efficient. The Power
Break gave me time to relax for 10 minutes and then I was able to come back to
work a little bit more focused.
Having our Power Break allowed us to break up the working day. Being off the
phone for 10 minutes gave us time to recoup and regather our thoughts and energy.
I was hesitant to acknowledge that Power Break would affect me in any way, but
toward the end of four weeks I found myself looking forward to it and my attitude
toward customers seemed to be a lot better just after each break.
I enjoyed the Power Break Program and felt it helped me relax and be able to
continue working without becoming to tired or distracted.
It was also evident from the feedback about the study that many of the
participants would like to continue doing the Power Break Program or a
similar program. The comments made by participants suggest that there is
a need for this type of workplace intervention to reduce stress and improve
work performance. The Power Break Program appears to be a simple and cost-
effective way to improve workplace wellness and productivity.
Compliance With the Power Break Program
In general, the compliance with the Power Break Program was high. In most
instances, lack of compliance was due to participants taking their regular days
off or taking holiday leave, rather than not wanting to participate. Thirty-
eight of the 43 participants in the Power Break treatment group completed
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190 Kennedy and Ball
compliance logs during the four-week trial. The maximum possible level of
compliance (100%) consisted of completing the Power Break 40 times (2
times per day x 20 days). The mean compliance level for the 38 subjects who
completed the log was M = 31.87 days (SD = 4.10), or in percentage terms,
79.68% compliance. The findings of this study indicate that the introduction
of time off to participate in short 10-minute Power Breaks in the workplace
would facilitate compliance and that it may be time well spent for both
employees and employers.
Satisfaction With the Power Break Program
Participants were requested to rate satisfaction with the Power Break Program
on a 5-point, single-item Likert scale with ratings varying from Strongly
disagree to Strongly agree. About 12% were not sure if Power Break was useful,
while the majority rated it as either moderately (25.6%) or strongly (55.8%)
useful.
Would you like to Continue Using a Power Break During Work?
Participants were also requested to rate whether they would like to continue
doing the Power Break Program on a 5-point, single-item Likert scale
with rating varying from Strongly disagree to Strongly agree. The majority
rated either moderately (27.9%) or strongly (58.1%) that they would like to
continue doing the Power Break Program.
Conclusions
The Power Break Program avoids the issues associated with power naps in
the corporate workplace. These problems are that people find it difficult to
fall asleep during daytime napping opportunities (Akerstedt, 1988), special
napping facilities are required, some people may sleep for too long, long
naps and even short naps may be associated with significant sleep inertia
(Dinges et al., 1985; Jewett et al., 1999), and many employers and employees
have a negative view of sleeping in the workplace during the day. The
Power Break Program reduced fatigue, negative mood and physical
symptoms and improved satisfaction with work in a telephone call centre.
Telephone call centres have a high turnover of staff due to the demands
of the work environment. Call centres can be stressful environments to
work in, because staff members have to deal with a wide range of human
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Power Break 191
emotions over the telephone and the work itself can be very repetitive. The
Power Break Program consisted of an effective, but minimal intervention
that could be adapted easily to most workplaces. The Power Break Program
also appeared to meet a psychological need of many of the participants and
it was effective in delivering a positive outcome to participants in this area.
Further studies need to be carried out to verify and extend the limited
findings of the present study. Future studies should also examine whether
short relaxation breaks like the Power Break program can be effective in
reducing sleepiness and sleepiness symptoms. The issue of sleepiness was
not addressed in the current study and sleepiness is a major issue in many
workplaces (Akerstedt, 1988).
REFERENCES
Akerstedt, T. (1988). Sleepiness as a consequence of shift work. Sleep, 11, 17–34.
Aschoff, J. (1994). Naps as integral parts of the wake time within the human sleep–wake
cycle. Journal of Biological Rhythms, 9, 145–155.
Baer, R. A. (2003). Mindfulness training as a clinical intervention: A conceptual and
empirical review. Clinical Psychology: Science and Practice, 10, 125–143.
Bogart, G. (1991) The use of meditation in psychotherapy: A review of the literature.
American Journal of Psychotherapy, 45, 383–412.
Bonnet, M. H. (1991). The effect of varying prophylactic naps on performance, alertness and
mood throughout a 52–hour continuous operation. Sleep, 14, 307–315.
Bonnet, M. H., & Arand, D. L. (1995). Consolidated and distributed nap schedules and
performance. Journal of Sleep Research, 4, 71–77.
Campbell, S. S., Dawson, D., & Zulley, J. (1993). When the human circadian system is caught
napping: Evidence for endogenous rhythms close to 24 hours. Sleep, 16, 638–640.
Canter, P. H., & Er nst, E. (2003). The cumulative effects of transcendental meditation
on cognitive function — a systematic review of randomised controlled trials. Weiner
Klinische Wochenschrift, 115, 758–766.
Dinges, D. F., Orne, M. T., & Orne, E. C. (1985). Assessing performance upon abrupt
awakening from naps during quasi-continuous operations. Behavior Research Methods,
Instruments and Computers, 17, 37–45.
Dunnell, K., & Cartwright, A. (1972). Medicine takers, prescribers and hoarders. London:
Routledge & Kegan Paul.
Gillberg, M. (1984). The effects of two alternative timings of a one-hour nap on early
morning performance. Biological Psychology, 19, 45–54.
Gillberg, M., Kecklund, G., Axelsson, J., & Akerstedt, T. (1996). The effects of a short
daytime nap after restricted night sleep. Sleep, 19, 570–575.
Grossman, P., Niemann, L., Schmidt, S., & Walach, H. (2004). Mindfulness-based stress
reduction and health benefits: A meta-analysis. Journal of Psychosomatic Research, 57, 35–43.
7568_Hypnosis_NOV2007.indd Sec1:1917568_Hypnosis_NOV2007.indd Sec1:191 4/1/08 11:45:11 AM4/1/08 11:45:11 AM
192 Kennedy and Ball
Gruzelier, J. H. (2002). A review of the impact of hypnosis, relaxation, guided imagery and
individual differences on aspects of immunity and health. Stress, 5, 147–163.
Harma, M., Knauth, P., & Ilmarinen, J. (1989). Daytime napping and its effects on
alertness and short-term memory performance in shiftworkers. International Archives of
Occupational and Environmental Health, 61, 341–345.
Haslam, D. R. (1985). Sleep depr ivation and naps. Behavior Research Methods, Instruments and
Computers, 17, 46–54.
Helmus, T., Rosenthal, L., Bishop, C., Roehrs, T., Syron, M. L., & Roth, T. (1997). Excessive
daytime sleepiness: The alerting effects of short and long naps in narcoleptic, sleep-
deprived, and alert individuals. Sleep, 20, 251–257.
Horne, J. A., & Reyner, L. A. (1996). Counteracting driver sleepiness: Effects of napping,
caffeine, and placebo. Psychophysiology, 33, 306–309.
Jewett, M. E., Wyatt, J. K., Ritz-De Cecco, A., Khalsa, S. B., Dijk, D. J., & Czeisler, C. A.
(1999). Time course of sleep inertia dissipation in human performance and alertness.
Journal of Sleep Research, 8, 1–8.
Lumley, M., Roehrs, T., Zorick, F., Lamphere, J., & Roth, T. (1986). The alerting effects of
naps in sleep-deprived subjects. Psychophysiology, 23, 403–408.
Matsumoto, K., & Harada, M. (1994). The effect of night-time naps on recovery from
fatigue following night work. Ergonomics, 37, 899–907.
McNair, D. M., Lorr, M., & Droppleman, L. F. (1981). Profile of Mood States manual. San
Diego: Educational and Industrial Testing Service.
Naitoh, P., Englund, C. E., & Ryman, D. (1982). Restorative power of naps in designing
continuous work schedules. Journal of Human Ergology, 11 (Suppl.), 259–278.
Naitoh, P., Kelly, T. L., & Babkoff, H. (1992). Napping, stimulant and four-choice
performance. In R. J. Broughton & R. D. Ogilvie (Eds.), Sleep, arousal and performance
(pp. 198–219). Boston: Birkhauser.
Reyner, L. A., & Horne, J. A. (1997). Suppression of sleepiness in drivers: Combination of
caffeine with a short nap. Psychophysiology, 34, 721–725.
Rosa, R. R. (1993). Napping at home and alertness on the job in rotating shift workers.
Sleep, 16, 727–735.
Russell, S. S., Spitzmuller, C., Lin, L. F., Stanton, J. M., Smith P. C., & Ironson, G. H.
(2004). Shorter can also be better: The Abridged Job in General Scale. Educational and
Psychological Measurement, 64, 878–893.
Sallinen, M., Harma, M., Akerstedt, T., Rosa, R., & Lillqvist, O. (1998). Promoting alertness
with a short nap during a night shift. Journal of Sleep Research, 7, 240–247.
Shacham, S. (1983). A shortened version of the profile of mood states. Journal of Personality
Assessment, 47, 305–306.
Smith, J. E., Richardson, J., Hoffman, C., & Pilkington, K. (2005). Mindfulness-based stress
reduction as supportive therapy in cancer care: Systematic review. Journal of Advanced
Nursing, 52, 315–327.
Smith, P. C., Kendall, L., & Hulin, C. L. (1969). The measurement of satisfaction in work and
retirement. Chicago: Rand McNally.
7568_Hypnosis_NOV2007.indd Sec1:1927568_Hypnosis_NOV2007.indd Sec1:192 4/1/08 11:45:11 AM4/1/08 11:45:11 AM
Power Break 193
Takahashi, M., & Arito, H. (2000). Maintenance of alertness and performance by a brief nap
after lunch under prior sleep deficit. Sleep, 23, 813–819.
Watson, D., & Pennebaker, J. W. (1989). Health complaints, stress and distress: Exploring the
central role of negative affectivity. Psychological Review, 96, 255–266.
7568_Hypnosis_NOV2007.indd Sec1:1937568_Hypnosis_NOV2007.indd Sec1:193 4/1/08 11:45:11 AM4/1/08 11:45:11 AM
