Outpatient rehabilitation as an intervention to improve employees’ physical capacity

Abstract

BACKGROUND: The aging of the workforce poses new challenges for maintaining work ability. Because of limited information on the effectiveness of vocational rehabilitation performed in traditional inpatient programs, extended interest in outpatient rehabilitation has risen in the past few years.

OBJECTIVE: We examined the effects of a new outpatient rehabilitation program where every participant defined their own goals to improve work ability by the aid of a goal-oriented multi-professional team. This report will focus on the employees’ physical capacity during a nine-month program.

METHODS: A total of 605 municipal employees from different production areas of the City of Tampere took part in the outpatient rehabilitation program, implemented by the occupational health unit. Groups of 12 employees participated in eight one-day sessions at intervals of two to three weeks; the final follow-up was 9 months from the beginning. Submaximal aerobic capacity was tested by a calibrated cycle ergometer with a commercial program (Aino Fitware pro, Helsinki, Finland). Musculoskeletal tests assessed muscle strength, balance and mobility.

RESULTS: During the 9-month follow-up of the rehabilitation program, the employees’ physical capacity was improved. The follow-up test scores from a total of 329 employees were significantly higher in the submaximal aerobic capacity test (p < 0.001). Other tests were also improved, such as standing on one foot (p = 0.001), back side bending flexibility test (p < 0.001), dynamic sit up (p = 0.001), upper extremity right (p < 0.001), and knee bending (p = 0.029). About 40% of the participants did not have an adequate health situation to take part in physical capacity tests; however they took part in the intervention.

CONCLUSIONS: The new outpatient rehabilitation program organized by the occupational health unit had a positive influence on employees’ physical capacity during a nine-month follow up.

Keywords

Health promotion work ability cognitive behavioral theory based training (CBTr)

1 Background

Europe’s workforce is rapidly aging. An aging workforce with a low education level, poor health, and a lack of physical activity is more likely to exit from work to early retirement [1, 2]. Robroek et al. suggested integrating occupational health promotion activities with activities aimed to increase physical fitness to maintain a productive workforce [3]. Occupational health and safety professionals consider physical exercise as an important tool to reach that goal [4 –7]. Robson et al. have made a systematic review of the effectiveness of Occupational Health and Safety (OHS) training programs and they found strong evidence for the effectiveness of training on workers’ behaviors, but insufficient evidence of its effectiveness on health [8].

Gram et al. performed a health promotion program with 20 minutes of exercise three times a week among construction workers, which got good results by decreasing the risk of cardio metabolic disorders and improving aerobic capacity. However, the program did not decrease musculoskeletal disorders or other negative work- related factors [4].

Lower aerobic capacity has been found to be one reason to be significantly related to sick leaves [6 , 10]. The occupational health services could in principle prevent sick leave by promotion of activities aimed at improving physical capacity, thus increasing work ability [1 , 11–15].

Suoyrjö et al. have studied Finnish vocationally oriented preventive institutional interventions and found that they temporarily reduce the risk of work disability [15]. On the other hand, Saltychev et al. found that institutional rehabilitation had little effect on health risk behaviors, such as alcohol consumption, poor physical activity, or prevalence of obesity [16], and early rehabilitation was more often granted to employees with only a few risk factors [17]. They suggest that preventive measures to reduce the risk of disability pension through rehabilitation should be targeted rather to high-risk employees [18]. Saltychev et al. also tested a multidisciplinary preventive program of physical training and psychological education to adopt a healthier lifestyle, and to achieve greater aerobic capacity, muscle strength and endurance, as well as better self-management of stress. After the intervention, they did not find any beneficial effects on perceived health. The program was similar to a primary prevention program widely used in Finland to reduce early retirement on health issues [19, 20].

Ohue et al. have researched a cognitive model and their results suggest that changing irrational beliefs to rational beliefs might prevent stress and burnout in nurses and could decrease the number of nurses who leave their position [21]. Stress, burn out and loss of position might be prevented by changing the way one thinks, by changing irrational beliefs to rational beliefs, facilitating positive automatic thoughts and abandoning negative automatic thoughts [21]. This new way of rehabilitation used in the present study was built to a cognitive behavioral theory based training (CBTr). Holtermann et al. described a framework for health-promoting interventions for four job groups by CBTr [22]. The overall aim of the study was to improve the safety margin between individual resources i.e. physical capacities, and cognitive and behavioral skills and physical work demands, and thereby reduce physical deterioration in a long-term perspective by interventions tailored for each job-group [22].

Our new concept for rehabilitation includes interdisciplinary, goal-oriented rehabilitation and teamwork by the rehabilitation staff as usual, but not disconnected from participants’ everyday life. Work ability has been seen as the balance between work and individual resources; when work and individual resources fit well together, work ability is good [23].

Traditionally, to qualify for inpatient rehabilitation, you must have a medical certificate with information about your illness and why your need this kind of rehabilitation. The practice in Finland is that first the insurance company (in Finland the Finnish Social Insurance Institution) accepts a person for inpatient rehabilitation; this has been followed by a rehabilitation examination at a rehabilitation center. The new concept of selection outpatient rehabilitation is faster, and the representative of the employer has an important role in the selection. The employer will pay the costs of the rehabilitation but gets reimbursement of the salary cost if the program is implemented during working hours, as this program was.

The rehabilitation program was designed together with the occupational health service and the employer’s representative, to meet the needs of the workplace and also to meet the planned expenses of the rehabilitation. The aim of the present study was to determine if a 9-month outpatient intervention program will increase the physical capacity of municipal employees.

2 Materials and methods

The ethics committee of Tampere University Hospital approved the study protocol, and written informed consent was obtained from all study participants. The selection of the participants for the rehabilitation was made by the occupational health service, which had the knowledge of current and previous diseases. The participation in the program was voluntary. The basic screening of the subjects was done by a multidisciplinary occupational team including a physician, a nurse, a physiotherapist and a psychologist. The employer, however, made the final decision whether it was possible for the person to be on leave from work during the outpatient rehabilitation days. A questionnaire given to the subjects before the physical tests included questions of health in general, including diseases, current and past smoking and physical exercise (times per week). Some basic laboratory measurements were done before the physician’s appointment. These included serum total cholesterol (mmoles/liter). Height (cm) and weight (kg) were recorded from which the body mass index was calculated [24]. This intervention was an early rehabilitation and the inclusion to the program was based on the participants’ own experience of their working capacity. The participation had to also meet the conditions set by the HR unit of the City of Tampere relating to steady employment relationship.

2.1 Study sample and the intervention

The participants in the study were employed by the city of Tampere, Finland which has 14,500 employees, of whom in all 605 (4.2%) were enrolled in the outpatient rehabilitation program (Fig. 1). Out of the 605 there were 17 (1.2%) subjects; who did not give consent to use their data in the study. Of the remaining 588 participants, 467 were women (79%) and 121 were men (21%). The mean age of subjects was 49.2 years (range 21–64 years).

12 persons in each of the 49 groups in the rehabilitation program met eight times at intervals of two weeks. Each gathering lasted for one day (8 hours). In addition there was a follow-up after 9 months, which was a three hour group meeting (Fig. 2). In this session the group reflected on how they had pursued their goals and how to go on after the total intervention.The groups were formed from employees who had slightly decreased work ability, which was based on the opinion of the employee, supervisor, and professional experience of occupational health. Each session was tailored for the needs of each group. An interdisciplinary, goal-oriented multi-professional team directed the groups. Goals were set together with the participants and every participant defined their own goals to improve work ability. The intervention days were chosen from the calendar together with the employer so as to interfere as little as possible with work flow. They consisted of different educational components such as physical training; social interaction, problem-solving skills at work and skills to talk about the work in everyday life; as well as individual goal setting. Each rehabilitation day included physical exercises in the program, including aerobic training, strength and endurance, mobility, balance and coordination training. Teaching subjects that were handled included nutrition (4 h), assets and coping, ergonomics and musculoskeletal diseases (4 h), intoxicants (2 h), sleep and relaxation practice (4 h), memory and brain health (2 h), exercise (10 h) and the everyday flow of work (4 h). Regarding physical capacity the learning process also included the theory of the different sub-elements of the motor areas, such as aerobic fitness, muscle strength, mobility, balance and coordination. It was considered as important that the learned items were transferred into everyday health related activity as soon as possible, in order to obtain a long-term effect [25].

The physical capacity was evaluated at the first three rehabilitation days. Prior to the physical tests conducted by occupational physiotherapists a physician examined the subjects.

2.2 Test protocols

The maximal oxygen intake (VO₂max) was estimated by a sub-maximal cardiovascular endurance tests with a bicycle ergometer (Ergoline^® 100K-ERG 161105, Bitz, Germany (accuracy under the directive DINVDE 0750-0238). The test result was analyzed with a commercial software program (Aino Health Management, FitWare pro^®, Helsinki, Finland). ACSM (2009a, 83) guidelines for low-risk tests suspension criteria were followed during testing [26].

Maximal oxygen consumption was compared with the reference values based on age and gender [27, 28]. Physical test results were compared with age and gender standardized reference values. Musculoskeletal tests assessed muscle strength, endurance and mobility. Standing on one foot balance – test result is maximally 60 seconds [29], back side bend flexibility test is measured in centimeters [29], grip maximum isometric strength of the hand and forearm muscles were measured by calibrated Jamar-Saehan –dynamometer in kilograms [30]. Dynamic sit up – repeated performance [31], upper extremity – test woman 5 kg and man 10 kg maximally 50 repetitions [32] and squatting test [33] were tested in standing position repeated performance during 30 s. The submaximal VO₂max tests and the musculoskeletal tests were done before and after intervention. First VO₂max tests were carried out individually during the first three days of rehabilitation and second VO₂max tests were done before the follow up meeting. Muscle tests were carried out during the first day in-group and before the follow up individually.

2.3 Statistical analyses

Statistical analyses were run by SPSS (Statistical Package for Social Sciences), version 20.0 (IBM, New York, NY, USA) software. Background characteristics of the study subjects who were included and those who were excluded from the physical testing were analyzed. Comparisons of physical functional test results before and after the nine-month rehabilitation program were divided by gender. Group differences were tested by Paired t-test if normally distributed and by Wilcoxon signed ranks tests if the parametric test was not suitable. For categorical variables the Mc Nemar test was applied. P values of less than 0.05 were considered significant.

Gender and age based formulas were done by syntax when analyzing VO₂max before and after intervention.

3 Results

Of a total of 588 participants, about 60% were tested for physical capacity. Subject recruitment from different vocational areas for the outpatient program is shown in Table 1. The largest participation for women came from health service (28.1%) and for men from construction work (25.2%). Inclusion criteria were that the unit’s management bought the course and the participants enrolled in the course, showing their interest. If the unit had an interest of more participants than planned for the size of the group, occupational health professionals and managers chose the participants. The exclusion criteria for physical capacity testing are shown in Table 2. The most common reasons for not testing were denial of testing by the physician, due to physical symptoms revealed at the examination, or elevated blood pressure and / or reported cardiac symptoms. Background characteristics for the subjects who were included and excluded from physical testing are shown in Table 3. The excluded subjects had significantly higher BMI, lower physical exercise activity and they were older than those who were included. The gender distribution was very similar.

During the nine-month follow-up of the rehabilitation program, the tested employees’ physical capacity clearly improved (Table 4). Improvement was seen in standing on one foot (women p = 0.009, men p = 0.016), backside bend flexibility (women and men p < 0.001), squatting (women p = 0.004 and men p = 0.001), dynamic sit up (women p < 0.000 and men p = 0.001), upper extremity right (women p = 0.69 and men p < 0.004), and upper extremity left (women p = 0.009 and men p = 0.005). Effect size by r squared was medium for back side bending (0.23) and squatting-test (0.09), other variables had small effect.

A total of 329 subjects participated in the submaximal cycle test. Detailed results of VO₂max results for each age group by gender are presented in Table 5. Table 6 shows aerobic capacity in baseline (VO₂max. ml/kg/min) stratified by gender and age based values, where the average fitness level is highlighted in gray.

Scores for submaximal cycle test increased significantly from the first test (VO₂max = 30.98±5.98 mL/(kg·min)) to the second test after nine months (VO₂ max = 31.6±6.4 ml/(kg·min)) (p < 0.001). All age groups and both genders increased their VO₂max result from the initial result (Fig. 3). During the intervention, there was no significant change in BMI (data not shown).

4 Discussion

In the present study, all age groups and both genders increased their VO₂max result from the initial result. All physical tests except grip strength improved significantly during the intervention. On the other hand, the results of grip strength were already moderately good at the first measurement. Although the majority of participants of the present study benefited from the intervention in terms of physical fitness, it may be that those who were in worst shape benefited the most, since improving an inadequate VO₂max might have even lifesaving benefits [34]. Low cardiorespiratory fitness is associated with higher all-cause mortality and cardiovascular events among healthy men and women [46]. On one hand, also testing process safety examination is important to plan properly. Surprisingly, when these precautions were followed, 40% did not pass the medical examination. We consider it extremely important that these subjects were found to take part in the intervention, and they most likely also received health benefits.

Understanding the importance of your test results in practice, including the importance of monitored heart rate, allows for better planning for training. This kind of learning is likely to contribute to improvement in aerobic fitness. In addition, participants described that the group caused positive pressure and increased motivation. In the group, progress of individual plans were reviewed at each session, which is known to be a motivation factor [35].

Aerobic test is the form of examination which provides much more information on the subject than the level of the aerobic condition, for example of abnormal reaction of blood pressure and heart rate to normal exertion. BMI change in this study did not explain the changes in aerobic fitness, and weight loss was not statistically significant at group level. This means that the improvement of aerobic fitness was most likely due to increased physical activity. The intervention was carried out in participants’ own community, which made lifestyle changes and learning in everyday life easier. This also poses a limitation to how one might extrapolate our findings to different populations, since the study sample represented municipal employees with the same ethnical background.

Low cardiorespiratory capacity was very common among young female home care workers, which is in line with earlier observations [36]. Physical tests are used in some tasks for the recruitment criteria to predict work ability, although there are studies which do not support for the use of muscle performance tests in work-related fitness evaluations [37]. It is apparent that work ability is multidimensional and not only dependent on physical fitness.

Overall the financial costs of rehabilitation worldwide are large. Many different rehabilitation programs of unclear efficacy are currently in use. It is clearly a challenge to identify the individual health risks of employees and target the measures to be taken accurately. Because of limited information on the effectiveness of traditional programs, extended interest in outpatient rehabilitation has risen in the past few years. Concept requirements for rehabilitation include interdisciplinary, goal-oriented rehabilitation and teamwork of rehabilitation staff.

Vocational rehabilitation is aimed at people entering or already in working life and whose work capacity has deteriorated or is at risk of deteriorating over the next few years. Although the study subjects showed, by the examination of the occupational health personnel and employer, only slight deterioration of work ability, about 40% of them were physically in such condition that they were not qualified by medical standards for physical testing. A big reason for this were cardiovascular problems, mainly elevated blood pressure. In Finland, it is estimated that over 48% of 25–64 year old adults have a mean systolic pressure of 140 mmHg or above, which is among the highest in Europe [38]. Thus, the intervention may not have been timely to those subjects who were not physically tested because of higher rates of health conditions, higher BMI and older age.

Social Insurance Institution (KELA) arrange institutional rehabilitation and follow-up of tests performed there is done by occupational health care. However, there exist a multitude of various tests, testing tools and testers, and reliable follow-ups to determine effectiveness of interventions have proven difficult in practice. The strength of the present intervention was that we used tests that were done in same way and in same place, which we believe increased the reliability of our findings.

Physical fitness is an important part of work ability and it might correlate with work ability index [39 –42]. Increased physical capacity as a result of the outpatient intervention may have positive consequences on work ability [39 –41]. The physical condition of participants of this study was on average poor at baseline and thus their work ability was at risk even though they comprised an early rehabilitation group. Regular physical activity can reduce also age-associated decline in functional capacity [7]. It is commonly known that behind the decrease in functional capacity is a progressive decline in the function of the cardiovascular system with increasing age. This can inhibit fulfilling job tasks and may eventually lead to an increase in work-related fatigue [36, 37].

The tentative conclusion of this study is that the nine-month outpatient rehabilitation intervention benefits physical capacity. Although every rehabilitation day included physical exercise, the main focus of this program was not in improving physical performance. We also consider that work ability is not dependent only on the physical fitness of the employee, since work itself and working conditions play an important role (43–45). This intervention also attempted to effect work and working environment in the way that supervisors were involved in the inclusion of employees and invited to the last session [43 –45]. Knowing the importance of commitment and interest is considered valuable in work rehabilitation [46].

Kuoppala et al. have made a systematic review studying multiple workplace factors and interventions that may affect workers’ health and well-being. Potentially effective activities were encouraging exercise, lifestyle, and ergonomics. Education and psychological interventions applied alone do not seem effective [6]. Low muscle strength is related to an increased risk for several chronic diseases and leg strength correlates positively to VO₂-max and physical function. Increased muscle strength improves daily function and quality of life [6].

The goal of employment, and the broad integrated approach of the present intervention by cognitive-behavioral process may motivate participants and the group to go on to a better direction in work, as well as self-care and leisure, as reflected by an improved physical ability. The learning process was involved in sub-regions of motor condition such as aerobic fitness, muscle strength, mobility, balance and agility. We do not yet know whether the increase in physical fitness achieved by the current program has affected work ability of the employees in question, in terms of e.g. reduced sick leave or increased performance. These preliminary findings warrant further investigation. The next steps in analyzing this population are to see whether the intervention has effects on parameters addressing work ability.

4.1 Limitations of the study

The subjects represent a relatively small population in Finland. Data on physical tests to analyze a possible health benefit of the intervention was not available for those with a medical contraindication for such testing, although they received the whole intervention. It cannot thus be concluded whether they received a benefit or not. Functional muscle tests were made first in-group and then individually, which may have affected the test results. One more limitation is that we cannot rule out that motor learning may have partly contributed to increased performance in follow-up of balance and musculoskeletal tests. Moreover, we did not have a control group for the physical tests, since appropriate funding for this was not available and it would have involved absence from work for the control employees involved.

4.2 Public health implications

Musculoskeletal disorders are still the main reason to work absenteeism, and exercise is an important means to prevent these problems [47]. Our results implicate that recommending an exercise part in work ability interventions is an effective instrument to promote physical activity. This may prevent musculoskeletal symptoms. It has also been shown previously that exercise alleviates mental health problems [48]. Good physical condition is important in maintaining work ability, and also as important for everyday life.

5 Conclusion

The present results suggest that a cognitive behavioral intervention as an early rehabilitation program is effective in increasing employees’ physical capacity.

Conflict of interest

None to report.

Authors’ contributions

All authors have been involved in the development of the study design. BO was responsible for the data collection and for writing the manuscript. STN and C-H.N participated in the general planning and coordination of the study and read and corrected draft versions of the manuscript and HH contributed as a statistician and commented the manuscript.

Footnotes

Acknowledgments

We wish to thank all employees who participated in this study and Tullinkulma Occupational Health Unit for co-operation and accomplishing the interventions and the personnel department of the city of Tampere Finland and all the participants. We thank Eeva Saarela, Tullinkulma Occupational Health Unit for the data management. We acknowledge the City of Tampere and all the participants and professionals who took part in this intervention.

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