Physical exposure during patient transfer and risk of back injury & low-back pain: prospective cohort study.

BACKGROUND: Work-related musculoskeletal disorders (MSDs) are common among healthcare workers. Because frequent patient transfer has been associated with increased risk of MSDs, we aim to quantify the physical load associated with commonly-used assistive devices and to investigate associations between accumulated physical exposure and risk of MSDs. METHODS: By applying an exposure matrix based on objective measurements of electromyography and trunk flexion on a large (n = 1285) prospective cohort, intensity of low-back pain (LBP) and odds of back injury at 1-year follow-up were modelled using linear models and logistic regressions, respectively. The cohort was divided into groups according to physical exposure; i.e. low (1st quartile), moderate (2nd and 3rd quartiles) and high (4th quartile) exposure. RESULTS: Exposure profiles are provided for 9 groups of assistive devices, with ceiling lifts and intelligent beds eliciting the lowest physical exposure. In the fully-adjusted model, we report differences in LBP intensity at follow-up between the low and moderate exposure groups (p = 0.0085). No difference was found between the moderate and high exposure groups (p = 0.2967). Likewise, we find no associations between physical exposure and odds of back injury at 1-year follow-up, with a prevalence of 11, 13 and 11% for the three groups, respectively. CONCLUSIONS: Low physical exposure during patient transfer was prospectively associated with lower intensity of LBP. Consistent use of assistive devices associated with low physical exposure, namely ceiling-lifts and intelligent beds, may play a role in reducing the incidence of MSDs among healthcare workers.

Biomechanical load during patient transfer with assistive devices: Cross-sectional study.

This study utilised a cross-sectional design to perform measurements of muscle activity as well as forward - and lateral trunk inclination angle during a full workday among 52 female healthcare workers from 16 different departments at five Danish hospitals. Using linear mixed models, the 95th percentile ranks of the normalised root mean square (nRMS) values were analysed for the different types of assistive devices. Compared to no assistive device (mean nRMS 27.9%, 95% CI 24.8%-31.0%), the use of intelligent beds (23.9%, CI 20.2%-27.6%) and ceiling-lifts (24.0%, CI 20.3%-27.7%) led to lower erector spinae nRMS values across all types of patient transfers. Conversely, the use of bedsheets (30.6%, CI 27.1%-34.2%), sliding-sheets (30.3%, CI 26.8%-33.9%) and sliding-boards (33.5%, CI 29.5%-37.6%) were associated with higher levels of erector spinae muscle activity.Consistent use of ceiling-lifts and intelligent beds reduces the physical workload and may thereby decrease the risk of musculoskeletal disorders among healthcare workers. Practioner Summary: Frequent patient transfer is associated with an increased risk of back pain and injury among healthcare workers. This analysis compares the level of physical load during patient transfer with commonly used assistive devices. The results show that use of the ceiling-lift and intelligent bed is associated with relatively low physical load during patient transfer. Abbreviations: RMS: root mean square; nRMS: normalized root mean square; EMG: electromyography; MSD: musculoskeletal disorder; LBP: low-back pain; VAS: visual analogue scale; MVC: maximal voluntary contraction.

Influence of between-limb asymmetry in muscle mass, strength, and power on functional capacity in healthy older adults.

PURPOSE: Numerous daily tasks such as walking and rising from a chair involve bilateral lower limb movements. During such tasks, lower extremity function (LEF) may be compromised among older adults. LEF may be further impaired due to high degrees of between-limb asymmetry. The present study investigated the prevalence of between-limb asymmetry in muscle mass, strength, and power in a cohort of healthy older adults and examined the influence of between-limb asymmetry on LEF. METHODS: Two hundred and eight healthy older adults (mean age 70.2 ± 3.9 years) were tested for LEF (400 m walking and 30-seconds chair stand). Furthermore, maximal isometric and dynamic knee extensor strength, leg extensor power, and lower limb lean tissue mass (LTM) were obtained unilaterally. RESULTS: Mean between-limb asymmetry in maximal muscle strength and power ranged between 10% and 13%, whereas LTM asymmetry was 3 ± 2.3%. Asymmetry in dynamic knee extensor strength was larger for women compared with men (15.0 ± 11.8% vs 11.1 ± 9.5%; P = .005) Leg strength and power were positively correlated with LEF (r2  = .43-.46, P < .001). The weakest leg was not a stronger predictor of LEF than the strongest leg. Between-limb asymmetry in LTM and isometric strength was negatively associated with LEF (LTM; r2  = .12, P = .005, isometric peak torque; r2  = 0.40, P = .03.) but dynamic strength and power were not. CONCLUSION: The present study supports the notion that in order to improve or maintain LEF, healthy older adults should participate in training interventions that increase muscle strength and power, whereas the effects of reducing between-limb asymmetry in these parameters might be of less importance.

Is fatigue after work a barrier for leisure-time physical activity? Cross-sectional study among 10,000 adults from the general working population.

AIM: In spite of the many health-related benefits of regular physical activity, fatiguing work may be a barrier to performing leisure-time physical activity. This study investigates the association between work-related fatigue and the duration of low- and high-intensity leisure-time physical activity in workers with sedentary and physically demanding jobs. METHODS: From the 2010 round of the Danish Work Environment Cohort Study, currently employed wage earners from the general working population ( N=10,427) replied to questions about work-related fatigue (predictor) and duration of low- and high-intensity leisure-time physical activity (outcome). Associations were modelled using general linear models controlling for various confounders. RESULTS: Among workers with physically demanding jobs, higher levels of work-related fatigue were associated with gradually lower levels of leisure-time physical activity - for low, moderate and high levels of work-related fatigue the duration of high-intensity leisure-time physical activity was 133 (95% confidence interval (CI) 127-178), 134 (95% CI 109-160) and 113 (95% CI 86-140) min per week, respectively (trend test p<0.001). The duration of high-intensity leisure-time physical activity was lower among older workers (≥50 years) compared to younger workers (<50 years) (132 ± 126 vs 168 ± 150 min per week) ( p<0.0001). CONCLUSIONS: The duration of high-intensity leisure-time physical activity gradually decreases with increased work-related fatigue in workers with physically demanding jobs. Older workers perform less high-intensity physical activity than younger workers. Workplaces should consider initiatives to allow workers with physically demanding jobs and older workers to perform physical exercise during working hours and thereby increase physical capacity to meet the job demands.

Physical workload and bodily fatigue after work: cross-sectional study among 5000 workers.

BACKGROUND: Persistent bodily fatigue after working days may indicate an imbalance between work demands and capacity of the workers. This study aimed to investigate associations between physical exposures at work and bodily fatigue after work. METHODS: Danish workers with physical work (N=5377) answered questions about various physical exposures during work and bodily fatigue after work in the 2010 round of the Danish Work Environment Cohort Study. Associations were modeled using binary logistic regression controlled for various confounders. RESULTS: Mean age among the younger (<50 years) and older (≥50 years) workers was 36 and 56 years, respectively. Younger and older workers exposed to various physical exposures (e.g. 'bending/twisting the back') for more than a quarter of the workday were more fatigued after work. An exposure-response relationship was observed between the number of physical exposures and bodily fatigue, with odds ratios (OR) for fatigue in the body among younger workers being 1.01 (95%CI 0.63-1.63), 1.59 (95%CI 1.01-2.50), 2.37 (95%CI 1.54-3.66) and 2.84 (95%CI 1.85-5.36) for 1, 2, 3 and ≥4 types of combined physical exposures, respectively. Correspondingly, for older workers, ORs were 1.95 (95%CI 1.09-3.51), 4.06 (95%CI 2.32-7.12), 4.10 (95%CI 2.28-7.37) and 4.90 (95%CI 2.72-8.82) for 1, 2, 3 and ≥4 exposures, respectively. CONCLUSION: While some of the single factor exposures were associated with increased bodily fatigue, the most marked associations were found when summing the number of different exposures. These results indicate that workplaces should focus on the sum of combined physical exposures rather than focusing solely on single exposures.

Effects of a Participatory Ergonomics Intervention With Wearable Technical Measurements of Physical Workload in the Construction Industry: Cluster Randomized Controlled Trial.

BACKGROUND: Construction work frequently involves heavy physical work, and a reduction of the physical workload should have high priority. Technological development has made it possible to obtain field measurements with surface electromyography (sEMG), kinematics measured with inertial measurement units (IMUs), and video recordings. However, no studies have used these methods simultaneously to detect situations with excessive physical workload (events) during a working day. Thus, knowledge about these specific events may combat work-related risk factors. Participatory ergonomics (PE) has shown promising results, but whether it can be used as a tool to reduce the physical workload during construction work remains unknown. OBJECTIVE: This cluster randomized controlled trial investigated whether a PE intervention with technical measurements consisting of IMUs, sEMG, heart rate monitoring, and video recordings of physical workload could reduce the number of events with excessive physical workload during a working day. Furthermore, other outcomes were obtained from questionnaires. METHODS: A total of 80 male full-time construction workers (aged 19 to 67 years) were randomized at the cluster level (gang) to a PE intervention consisting of 3 workshops (7 gangs and 32 workers) or to a control group (8 gangs and 48 workers). The physical workload was recorded by technical measurements, that is, IMUs, sEMG, heart rate monitoring, and video recordings during a full working day at baseline and 3 and 6 months' follow-up. On the basis of the technical measurements, a custom-made computer program detected the situations (events) where the construction workers were exposed to excessive physical workload and used in the intervention. Differences in the number of events from baseline to follow-up between intervention and control were evaluated using linear mixed models (intention-to-treat), with individual nested in cluster as a random factor. Furthermore, questionnaires were filled out on test days. RESULTS: The results of the primary outcome showed no change in the number of events with excessive physical workload. However, compared with the control group, the other outcomes showed decreased general fatigue after a typical working day (P=.001) and increased influence on own work (P=.04). CONCLUSIONS: This PE intervention with technical measurements did not reduce the number of events with excessive physical workload during construction work. However, the intervention led to decreased general fatigue and increased influence on own work. TRIAL REGISTRATION: ClinicalTrials.gov NCT02498197; https://clinicaltrials.gov/ct2/show/NCT02498197 (Archived by WebCite at http://www.webcitation.org/74SZ3DIWS).

Influence of different attentional focus on EMG amplitude and contraction duration during the bench press at different speeds.

The purpose of this study was to investigate whether using different focus affects electromyographic (EMG) amplitude and contraction duration during bench press performed at explosive and controlled speeds. Eighteen young male individuals were familiarized with the procedure and performed the one-maximum repetition (1RM) test in the first session. In the second session, participants performed the bench press exercise at 50% of the 1RM with 3 different attentional focuses (regular focus on moving the load vs contracting the pectoralis vs contracting the triceps) at 2 speed conditions (controlled vs maximal speed). During the controlled speed condition, focusing on using either the pectoralis or the triceps muscles increased pectoralis normalized EMG (nEMG) by 6% (95% CI 3-8%; p = 0.0001) and 4% nEMG (95% CI 1-7%; p = 0.0096), respectively, compared with the regular focus condition. Triceps activity was increased by 4% nEMG (95% CI 0-7%; p = 0.0308) at the controlled speed condition during the triceps focus. During the explosive speed condition, the use of different focuses had no effect. The different attentional focus resulted in comparable contraction duration for the measured muscles when the exercise was performed explosively. Using internal focus to increase EMG amplitude seems to function only during conditions of controlled speed.

Hand strengthening exercises in chronic stroke patients: Dose-response evaluation using electromyography.

STUDY DESIGN: Cross-sectional. PURPOSE OF THE STUDY: This study evaluates finger flexion and extension strengthening exercises using elastic resistance in chronic stroke patients. METHODS: Eighteen stroke patients (mean age: 56.8 ± 7.6 years) with hemiparesis performed 3 consecutive repetitions of finger flexion and extension, using 3 different elastic resistance levels (easy, moderate, and hard). Surface electromyography was recorded from the flexor digitorum superficialis (FDS) and extensor digitorum (ED) muscles and normalized to the maximal electromyography of the non-paretic arm. RESULTS: Maximal grip strength was 39.2 (standard deviation: 12.5) and 7.8 kg (standard deviation: 9.4) in the nonparetic and paretic hand, respectively. For the paretic hand, muscle activity was higher during finger flexion exercise than during finger extension exercise for both ED (30% [95% confidence interval {CI}: 19-40] vs 15% [95% CI: 5-25] and FDS (37% [95% CI: 27-48] vs 24% [95% CI: 13-35]). For the musculature of both the FDS and ED, no dose-response association was observed for resistance and muscle activity during the flexion exercise (P > .05). CONCLUSION: The finger flexion exercise showed higher muscle activity in both the flexor and extensor musculature of the forearm than the finger extension exercise. Furthermore, greater resistance did not result in higher muscle activity during the finger flexion exercise. The present results suggest that the finger flexion exercise should be the preferred strengthening exercise to achieve high levels of muscle activity in both flexor and extensor forearm muscles in chronic stroke patients. The finger extension exercise may be performed with emphasis on improving neuromuscular control. LEVEL OF EVIDENCE: 4b.

Psychosocial benefits of workplace physical exercise: cluster randomized controlled trial.

BACKGROUND: While benefits of workplace physical exercise on physical health is well known, little is known about the psychosocial effects of such initiatives. This study evaluates the effect of workplace versus home-based physical exercise on psychosocial factors among healthcare workers. METHODS: A total of 200 female healthcare workers (Age: 42.0, BMI: 24.1) from 18 departments at three hospitals were cluster-randomized to 10 weeks of: 1) home-based physical exercise (HOME) performed alone during leisure time for 10 min 5 days per week or 2) workplace physical exercise (WORK) performed in groups during working hours for 10 min 5 days per week and up to 5 group-based coaching sessions on motivation for regular physical exercise. Vitality and mental health (SF-36, scale 0-100), psychosocial work environment (COPSOQ, scale 0-100), work- and leisure disability (DASH, 0-100), control- (Bournemouth, scale 0-10) and concern about pain (Pain Catastrophizing Scale, scale 0-10) were assessed at baseline and at 10-week follow-up. RESULTS: Vitality as well as control and concern about pain improved more following WORK than HOME (all p < 0.05) in spite of increased work pace (p < 0.05). Work- and leisure disability, emotional demands, influence at work, sense of community, social support and mental health remained unchanged. Between-group differences at follow-up (WORK vs. HOME) were 7 [95% confidence interval (95% CI) 3 to 10] for vitality, -0.8 [95% CI -1.3 to -0.3] for control of pain and -0.9 [95% CI -1.4 to -0.5] for concern about pain, respectively. CONCLUSIONS: Performing physical exercise together with colleagues during working hours was more effective than home-based exercise in improving vitality and concern and control of pain among healthcare workers. These benefits occurred in spite of increased work pace. TRIAL REGISTRATION: NCT01921764 at ClinicalTrials.gov . Registered 10 August 2013.

Mind-muscle connection training principle: influence of muscle strength and training experience during a pushing movement.

PURPOSE: To investigate the effect of different attentional focus conditions on muscle activity during the push-up exercise and to assess the possible influence of muscle strength and training experience. METHODS: Eighteen resistance-trained men performed 1RM bench press testing and were familiarized with the procedure during the first session. In the second session, three different conditions were randomly performed: regular push-up and push-up focusing on using the pectoralis major and triceps brachii muscles, respectively. Surface electromyography (EMG) was recorded and analyzed (EMG normalized to max; nEMG) for the triceps brachii and pectoralis major muscles. RESULTS: Participants had on average 8 (SD 6) years of training experience and 1RM of 1.25 (SD 0.28) kg per kg bodyweight. Focusing on using pectoralis major increased activity in this muscle by 9% nEMG (95% CI 5-13; Cohen's d 0.60) compared with the regular condition. Triceps activity was not significantly influenced by triceps focus although borderline significant, with a mean difference of 5% nEMG (95% CI 0-10; Cohen's d 0.30). However, years of training experience was positively associated with the ability to selectively activate the triceps (ß = 0.41, P = 0.04), but not the pectoralis. Bench press 1RM was not significantly associated with the ability to selectively activate the muscles. CONCLUSION: Pectoralis activity can be increased when focusing on using this muscle during push-ups, whereas the ability to do this for the triceps is dependent on years of training experience. Maximal muscle strength does not appear to be a decisive factor for the ability to selectively activate these muscles.

High-intensity preoperative training improves physical and functional recovery in the early post-operative periods after total knee arthroplasty: a randomized controlled trial.

PURPOSE: The benefits of preoperative training programmes compared with alternative treatment are unclear. The purpose of this study was to evaluate the effectiveness of a high-intensity preoperative resistance training programme in patients waiting for total knee arthroplasty (TKA). METHODS: Forty-four subjects (7 men, 37 women) scheduled for unilateral TKA for osteoarthritis (OA) during 2014 participated in this randomized controlled trial. Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), the Physical Functioning Scale of the Short Form-36 questionnaire (SF-36), a 10-cm visual analogue scale (VAS), isometric knee flexion, isometric knee extension, isometric hip abduction, active knee range of motion and functional tasks (Timed Up and Go test and Stair ascent-descent test) were assessed at 8 weeks before surgery (T1), after 8 weeks of training (T2), 1 month after TKA (T3) and finally 3 months after TKA (T4). The intervention group completed an 8-week training programme 3 days per week prior to surgery. RESULTS: Isometric knee flexion, isometric hip abduction, VAS, WOMAC, ROM extension and flexion and all the functional assessments were greater for the intervention group at T2, T3 and T4, whereas isometric knee extension was greater for this group at T2 and T4 compared with control. CONCLUSION: The present study supports the use of preoperative training in end-stage OA patients to improve early postoperative outcomes. High-intensity strength training during the preoperative period reduces pain and improves lower limb muscle strength, ROM and functional task performance before surgery, resulting in a reduced length of stay at the hospital and a faster physical and functional recovery after TKA. The present training programme can be used by specialists to speed up recovery after TKA. LEVEL OF EVIDENCE: I.

Electromyographic Comparison of Elastic Resistance and Machine Exercises for High-Intensity Strength Training in Patients With Chronic Stroke.

OBJECTIVE: To investigate whether elastic resistance training can induce comparable levels of muscle activity as conventional machine training in patients with chronic stroke. DESIGN: Comparative study. SETTING: Outpatient rehabilitation facility. PARTICIPANTS: Stroke patients (N=18) with hemiparesis (mean age, 57 ± 8y). INTERVENTIONS: Patients performed 3 consecutive repetitions at 10 repetition maximum of unilateral knee extension and flexion using elastic resistance and conventional machine training. MAIN OUTCOME MEASURES: Surface electromyography was measured in vastus lateralis, vastus medialis, biceps femoris, and semitendinosus and was normalized to maximal electromyography (% of max) of the nonparetic leg. RESULTS: In the paretic leg, agonist muscle activity ranged from 18% to 24% normalized electromyography (% of max) (nEMG) during knee flexion and from 32% to 40% nEMG during knee extension. For knee extension, vastus lateralis nEMG was higher during machine exercise than during elastic resistance exercise (40% [95% confidence interval {CI}, 33-47] vs 32% [95% CI, 25-39]; P=.003). In the nonparetic leg, agonist muscle activity ranged from 54% to 61% during knee flexion and from 52% to 68% during knee extension. For knee flexion semitendinosus nEMG was higher (61% [95% CI, 50-71] vs 54% [95% CI, 44-64]; P=.016) and for knee extension vastus medialis nEMG was higher (68% [95% CI, 60-76] vs 56% [95% CI, 48-64]; P<.001) during machine exercise than during elastic resistance exercise. By contrast, antagonist coactivation was significantly higher during knee flexion when performed using elastic resistance compared with the machine. Lastly, there were no differences in perceived exertion between exercise modalities. CONCLUSIONS: Machine training appears to induce slightly higher levels of muscle activity in some of the investigated muscles compared to elastic resistance during lower limb strength training in patients with chronic stroke. The higher level of coactivation during knee flexion when performed using elastic resistance suggests that elastic resistance exercises are more difficult to perform. This is likely due to a higher level of movement instability.

Football training in men with prostate cancer undergoing androgen deprivation therapy: activity profile and short-term skeletal and postural balance adaptations.

PURPOSE: To investigate the activity profile of football training and its short-term effects on bone mass, bone turnover markers (BTMs) and postural balance in men with prostate cancer (PCa) undergoing androgen deprivation therapy (ADT). METHODS: This was a randomised 12-week study in which men with PCa undergoing ADT were assigned to a football intervention group [FTG, n = 29, 67 ± 7 (±SD) years] training 2‒3 times per week for 45‒60 min or to a control group (n = 28, 66 ± 5 years). The activity profile was measured using a 5-Hz GPS. The outcomes were total body and leg bone mineral content (BMC) and density, BTMs and postural balance. RESULTS: In the last part of the 12 weeks, FTG performed 194 ± 41 accelerations and 296 ± 65 decelerations at >0.6 m/s/s and covered a distance of 905 ± 297 m at speeds >6 km/h and 2646 ± 705 m per training session. Analysis of baseline-to-12-week change scores showed between-group differences in favour of FTG in total body BMC [26.4 g, 95 % confidence interval (CI): 5.8-46.9 g, p = 0.013], leg BMC (13.8 g, 95 % CI: 7.0‒20.5 g, p < 0.001) and markers of bone formation: P1NP (36.6 µg/L, 95 % CI: 10.4‒62.8 µg/L, p = 0.008) and osteocalcin (8.6 µg/L, 95 % CI: 3.3‒13.8 µg/L, p < 0.01). The number of decelerations correlated to the increase in leg BMC (r = 0.65, p = 0.012). No between-group differences were observed for the remaining outcomes. CONCLUSION: Football training involves numerous runs, accelerations and decelerations, which may be linked to marked increases in bone formation markers and preserved bone mass in middle-aged and elderly men with PCa undergoing ADT. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01711892.

Regular use of pain medication due to musculoskeletal disorders in the general working population: Cross-sectional study among 10,000 workers.

BACKGROUND: We aimed to determine the association between work, health, and lifestyle with regular use of pain medication due to musculoskeletal disorders in the general working population. METHODS: Currently employed wage earners (N = 10,024) replied to questions about health, work, and lifestyle. The odds for regularly using medication for musculoskeletal disorders were modeled using logistic regression controlled for various confounders. RESULTS: Pain intensity increased the odds for using pain medication in a dose-response fashion. With seated work as reference, the odds for using pain medication were 1.26 (95%CI: 1.09-1.47) for workers engaged in standing or walking work that is not strenuous and 1.59 (95%CI: 1.39-1.82) for workers engaged in standing or walking work with lifting tasks or heavy and fast strenuous work. CONCLUSIONS: Workers with higher levels of physical activity at work are more likely to use pain medication on a regular basis for musculoskeletal disorders, even when adjusting for pain intensity, lifestyle, and influence at work. Am. J. Ind. Med. 59:934-941, 2016. © 2016 Wiley Periodicals, Inc.

Participatory organizational intervention for improved use of assistive devices for patient transfer: study protocol for a single-blinded cluster randomized controlled trial.

BACKGROUND: Epidemiological studies have shown that patient transfer is a risk factor for back pain, back injuries and long term sickness absence, whereas consistent use of assistive devices during patient transfer seems to be protective. While classical ergonomic interventions based on education and training in lifting and transferring techniques have not proven to be effective in preventing back pain, participatory ergonomics, that is meant to engage and motivate the involved parties while at the same time making the intervention maximally relevant, may represent a better solution. However, these findings are largely based on uncontrolled studies and thus lack to be confirmed by studies with better study designs. In this article, we present the design of a study which aims to evaluate the effect and process of a participatory organizational intervention for improved use of assistive devices. METHODS: The study was performed as a cluster randomized controlled trial. We recruited 27 departments (clusters) from five hospitals in Denmark to participate in the study. Prior to randomization, interviews, observations and questionnaire answers (baseline questionnaire) were collected to gain knowledge of barriers and potential solutions for better use of assistive devices. In April 2016, the 27 departments were randomly allocated using a random numbers table to a participatory intervention (14 clusters, 324 healthcare workers) or a control group (13 clusters, 318 healthcare workers). The participatory intervention will consist of workshops with leaders and selected healthcare workers of each department. Workshop participants will be asked to discuss the identified barriers, develop solutions for increasing the use of assistive devices and implement them in their department. Use of assistive devices (using digital counters -, primary outcome, and accelerometers and questionnaire - secondary outcome), perceived physical exertion during patient transfer, pain intensity in the lower back, occurrence of work-related back injuries during patient transfer, organizational readiness to change, knowledge on how to perform proper patient transfer, social capital and work ability (secondary outcomes) were assessed at baseline and will also be assessed at 1 year follow-up. Process evaluation will be based on qualitative and quantitative data to assess the implementation, the change process, and the impact of context aspects. DISCUSSION: The study will evaluate the effect and process of a participatory intervention on improving the use of assistive devices for patient transfer among hospital healthcare workers. By using cluster-randomization, as well as process- and effect evaluation based on objective measures we will contribute to the evidence base of a promising intervention approach. TRIAL REGISTRATION: ClinicalTrials.gov ( NCT02708550 ). March, 2016.

Associations between biopsychosocial factors and chronic upper limb pain among slaughterhouse workers: cross sectional study.

BACKGROUND: Knowledge of factors associated with chronic pain is necessary for preventive strategies. The present study investigates biopsychosocial differences, with specific focus on rate of force development (RFD) and work ability, between workers with and without chronic upper limb pain. METHODS: Eighty-two male slaughterhouse workers, 49 with chronic upper limb pain and 33 pain-free controls participated in the study. Maximal muscle strength, RFD, and muscle activity was determined from fast and forceful maximal voluntary contractions for the shoulder and hand. Participants filled out a questionnaire on work ability (work ability index), work disability (Work module of DASH questionnaire), fear avoidance, and self-rated health. Additionally, pressure pain threshold (PPT) was measured in muscles of the arm, shoulder and lower leg. RESULTS: Muscle strength and RFD (determined within time intervals of 30, 50, 100, and 200 ms relative to onset of contraction) was 28 % and 58-78 % lower, respectively, in workers with chronic pain compared with pain-free controls, and paralleled by reduced muscle activity (all p < 0.001). Workers with chronic pain had lower PPT of the arm, shoulder and lower leg (p < 0.01), and reported impaired work ability index score and general health along with higher work disability and fear avoidance compared with controls (all p < 0.0001). No differences were observed between the groups in regard to age, BMI, physical activity level, job position and duration of slaughterhouse work (all p > 0.4). CONCLUSIONS: Chronic upper limb pain was paralleled by reduced neuromuscular function of the shoulder and hand along with impaired work ability, work disability and general health. Future studies on chronic pain management at the workplace should carefully consider the biopsychosocial nature of pain when designing and implementing preventive strategies.

Effects of Slackline Training on Postural Control, Jump Performance, and Myoelectrical Activity in Female Basketball Players.

The main goal of the study was to assess the effects of slackline training on the postural control system and jump performance of athletes. Twenty-five female basketball players were randomized into 2 groups: control (N = 12) and experimental (N = 13). The latter experienced a 6-week supervised slackline training (3 sessions per week, 5-9 minutes per session). Participants underwent center of pressure (CoP) testing through three 10-second tasks (bipedal, left leg, and right leg support) over firm and compliant surfaces with eyes open. Several CoP parameters were assessed: length, area, length/area, speed, Ymean, Xmean, deltaY, deltaX, RMS (root-mean-squared amplitude of the CoP), RMSY, and RMSX. Surface electromyography recordings were obtained too. Participants were also tested on jump performance, provided perceived exertion (6-20 Borg scale) and local muscle perceived exertion. Center of pressure parameters significantly differed before and after training only in the experimental group and only on the compliant surface (left leg: length, area, speed, deltaY, and deltaX; right leg: length, speed, Ymean, deltaY, and RMSY). Surface electromyography recordings were comparable before and after training in both groups. Performance on a countermovement jump test significantly improved only in the experimental group (effect side was 3.21 and 1.36 [flight time and jump height, respectively], which is described as a large effect). Mechanical power of the legs, as measured through the 30-second maximal performance jump test, did not improve in either group. The slackline training was rated as "somewhat hard" with the quadriceps, soleus, and gastrocnemius being rated as the most engaged muscles. Data indicate that slacklining requires activation of the main lower limb muscles. On conclusion, slacklining may be a valid cross-training tool for female basketball players.

Reliability of Mechanical Trunk Responses During Known and Unknown Trunk Perturbations.

This study evaluates the between-day reliability of a newly developed trunk perturbation test and compares mechanical response during known and unknown conditions. Mechanical trunk responses were measured in 17 female subjects during unloading and loading perturbations of the abdomen (A: preloaded abdomen condition) and low back (B: preloaded back condition). The loading perturbation increased the preload from 5.5 kg to a 10.9 kg pull on the trunk whereas the unloading perturbation decreased the pull from 5.5 kg to 0.1 kg. A sequence of loading (known), unloading (known), and randomized loading/unloading (unknown) perturbations were performed for A and B. Between-day reliability of stopping time, trunk displacement, and velocity was quantified using intraclass correlation coefficients (ICCs). ICCs were good to excellent for all loading and unloading measures during the known (0.70-0.98) and unknown (0.64-0.94) perturbations of A and B. In general, larger trunk displacements were seen after the unknown perturbations compared with the known perturbation. The method may be used as a diagnostic tool for screening workers who are in risk of future work-related low back injuries.

Dose-response association between leisure time physical activity and work ability: Cross-sectional study among 3000 workers.

INTRODUCTION: Regular physical activity is important for longevity and health, but knowledge about the optimal dose of physical activity for maintaining good work ability is unknown. This study investigates the association between intensity and duration of physical activity during leisure time and work ability in relation to physical demands of the job. METHODS: From the 2010 round of the Danish Work Environment Cohort Study, currently employed wage earners with physically demanding work (n = 2952) replied to questions about work, lifestyle and health. Excellent (100 points), very good (75 points), good (50 points), fair (25 points) and poor (0 points) work ability in relation to the physical demands of the job was experienced by 18%, 40%, 30%, 10% and 2% of the respondents, respectively. RESULTS: General linear models that controlled for gender, age, physical and psychosocial work factors, lifestyle and chronic disease showed that the duration of high-intensity physical activity during leisure was positively associated with work ability, in a dose-response fashion (p < 0.001). Those performing ⩾ 5 hours of high-intensity physical activity per week had on average 8 points higher work ability than those not performing such activities. The duration of low-intensity leisure-time physical activity was not associated with work ability (p = 0.5668). CONCLUSIONS: The duration of high-intensity physical activity during leisure time is associated in a dose-response fashion with work ability, in workers with physically demanding jobs.

Effect of physical exercise on workplace social capital: Cluster randomized controlled trial.

AIMS: While workplace health promotion with group-based physical exercise can improve workers' physical health, less is known about potential carry-over effects to psychosocial factors. This study investigates the effect of physical exercise on social capital at work. METHODS: Altogether, 200 female healthcare workers (nurses and nurse's aides) from 18 departments at three hospitals were randomly allocated at the department level to 10 weeks of (1) group-based physical exercise at work during working hours or (2) physical exercise at home during leisure time. At baseline and follow-up, participants replied to a questionnaire concerning workplace social capital: (1) within teams (bonding); (2) between teams (bridging); (3) between teams and nearest leaders (linking A); (4) between teams and distant leaders (linking B). RESULTS: At baseline, bonding, bridging, linking A and linking B social capital were 74 (SD 17), 61 (SD 19), 72 (SD 22) and 70 (SD 18), respectively, on a scale of 0-100 (where 100 is best). A group by time interaction was found for bonding social capital (P=0.02), where physical exercise at work compared with physical exercise during leisure time increased 5.3 (95% confidence interval 2.3- 8.2)(effect size, Cohen's d = 0.31) from baseline to follow-up. For physical exercise at home during leisure time and exercise at work combined, a time effect (P=0.001) was found for linking A social capital, with a decrease of 4.8 (95% confidence interval 1.9-7.6). CONCLUSIONS: Group-based physical exercise at work contributed to building social capital within teams at the workplace. However, the general decrease of social capital between teams and nearest leaders during the intervention period warrants further research.