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The purpose of this study was to identify if workplace interventions, (i.e., mindfulness classes and monetary incentives for gym attendance), influenced workers' physical activity. Office-based participants were randomized into one of four intervention assignments: 1) CONTROL (no interventions) (n = 40), 2) MINDFULNESS (n = 33), 3) GYM INCENTIVE (n = 41), or 4) BOTH mindfulness and gym incentive (n = 31). Activity-tracker and self-reported metabolic expenditure and step counts were gathered between January 2020 and December 2020 whereas the eight-week long interventions were provided between January and March 2020, when the impact of COVID-19 pandemic started. While physical activity decreased during the follow-up months, percent changes of physical activity at 1-, 2-, and 9-month follow-ups compared to baseline show no significant differences between or across the four intervention assignments (p > 0.05). These results suggest that the intervention assignments had no effect on physical activity from baseline. The lack of effectiveness of these interventions on participant physical activity could be attributed to the influence of the COVID-19 pandemic, and any effects of the interventions could not outweigh the effects of the pandemic., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Previous studies on Human Factors and Ergonomics (HFE) have primarily examined the impact of Work-From-Home (WFH) on worker health and well-being, yet little research has examined the optimal implementation process of WFH programs. Work systems perspective suggests that organizational policies, leadership, and psychological factors collectively influence the success of organizational change efforts. Our study explored the roles of managerial/supervisory, psychological, and organizational policy factors in facilitating the relationship between employees' HFE awareness and their acceptance and satisfaction with the WFH arrangement. Using data from 3195 knowledge workers in the US who use computers as their primary work tool and have worked from home at least one day in the past 30 days, we employed structural equation modeling to test our hypotheses. Transformational HFE leadership and employees' general self-efficacy are pivotal in implementing ergonomic WFH arrangements. The combination of employees' HFE awareness, transformational HFE leadership, and adequate levels of self-efficacy may foster positive process outcomes (e.g., readiness for WFH arrangement, workspace design satisfaction) in WFH arrangements. Efforts that are coordinated across organizational levels determine the effectiveness of organizational change., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Jin Lee, Jia-Hua Lin, Stephen S. Bao, Michelle M. Robertson., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

After the onset of the COVID-19 pandemic, many office workers transitioned to working-from-home (WFH) which altered routine physical activity (PA). To understand how these workers' PA were affected throughout the pandemic, PA data collected in January, April, June, and December 2020 with an activity tracker and a validated survey were analyzed. Between January and December, it was found that step counts during the weekday decreased (p < 0.01), weekday heart rate was higher than weekends (p < 0.01), activity-tracker and self-reported PA decreased (p < 0.01), and sitting time increased (p < 0.01). To understand the agreement between the objective and subjective METs, Bland-Altman analyses were completed and demonstrated an acceptable level of agreement. Findings show decreased level of PA amongst WFH office workers and that the activity tracker and survey are reliable methods of recording WFH PA., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Janitors' jobs require repetitive work with low control (skill discretion, decision authority) and social support. Previous studies have found this constellation of work conditions leads to high stress levels. This study investigated the relationships among job demand-control-support, burnout, and musculoskeletal symptoms for commercial janitors in Washington State. Structural equation modeling was performed using data from 208 participants with analyses comparing models of daytime and nighttime janitors. Burnout fully mediated the relationship between job demands and musculoskeletal complaints among daytime janitors. Among nighttime janitors, burnout mediated between job demands, job control, and social support, and musculoskeletal complaints. The nighttime janitors' model was more fully supported compared to the daytime model. This study is one of a small number that examine and bring attention to the importance of janitors' burnout. Recommendations to improve the psychosocial work environment toward mitigating burnout and reducing musculoskeletal complaints are provided., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Workers performing cleaning duties experience higher injury rates, especially in the form of musculoskeletal disorders (MSDs), than other industries. It is essential to understand the inherent risks associated with the nature of this occupation. Based on the Balance Theory (Smith & Carayon-Sainfort, 1989), this review surveys the current literature, especially those published since the previous review paper (Kumar & Kumar, 2008), and identifies which elements contributing to MSD risks were examined: task, technology, organization, environment, individual, and their interactions. Thirty-nine research papers published between 2005 and 2021 are identified and summarized. Among these papers, task and individual elements received the most attention, at 42 and 34 occurrences, respectively. The interaction elements of technology-organization, technology-environment, and organization-environment received less than three mentions. The goal of this literature review is to update the knowledge base and identify current trends for the cleaning occupation. Possible interventions for risk reduction and future research directions are suggested., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Cranking the landing gear is a common task performed by truck drivers to raise or lower trailers. This task poses a risk to the shoulder joint due to the required forceful exertion and the posture constrained to the hand-handle interface. As a potential occupational risk, there has been no definitive guideline for best practices among truck drivers. An operator can crank perpendicular (frontal) or parallel (sagittal) to the crank rotation. In this laboratory study, the effects of cranking method and resistance on scapular range of motion and shoulder muscle activity were observed in 12 participants. Scapular posture was measured using an optical motion tracking system. EMG was monitored on 16 muscles contributing to shoulder movement. The results show that during frontal cranking, the scapular range of protraction was 28 ± 11.6°, which was more than the sagittal cranking (23 ± 10.4°), indicating a decreased subacromial space and elevated shoulder impingement risk. Seven muscles (all three deltoid muscles, middle trapezius, supraspinatus, infraspinatus, and teres minor) demonstrated that when the crank resistance was low, the front cranking method resulted in lower activity than the side cranking. When the crank resistance was 20 Nm, the muscle activity on these seven muscles was greater when cranking from the front than from the side. Based on these observations, we suggest that when the resistance is low (lowering the trailer) the driver should stand facing the trailer. On the contrary, it is advantageous to stand parallel to the trailer and crank while raising the trailer to apply the full body strength to reduce the shoulder load., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Shoulder joint kinematics has been used as a representative indicator to investigate musculoskeletal symptoms among computer users for office ergonomics studies. The traditional measurement of shoulder kinematics normally requires a laboratory-based motion tracking system which limits the field studies. In the current study, a portable, low cost, and marker-less Microsoft Kinect™ sensor was examined for its feasibility on shoulder kinematics measurement during computer tasks. Eleven healthy participants performed a standardized computer task, and their shoulder kinematics data were measured by a Kinect sensor and a motion tracking system concurrently. The results indicated that placing the Kinect sensor in front of the participants would yielded a more accurate shoulder kinematics measurements then placing the Kinect sensor 15° or 30° to one side. The results also showed that the Kinect sensor had a better estimate on shoulder flexion/extension, compared with shoulder adduction/abduction and shoulder axial rotation. The RMSE of front-placed Kinect sensor on shoulder flexion/extension was less than 10° for both the right and the left shoulder. The measurement error of the front-placed Kinect sensor on the shoulder adduction/abduction was approximately 10° to 15°, and the magnitude of error is proportional to the magnitude of that joint angle. After the calibration, the RMSE on shoulder adduction/abduction were less than 10° based on an independent dataset of 5 additional participants. For shoulder axial rotation, the RMSE of front-placed Kinect sensor ranged between approximately 15° to 30°. The results of the study suggest that the Kinect sensor can provide some insight on shoulder kinematics for improving office ergonomics., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Although one-handed pulling is commonly used in many tasks, normative data on the populational strength capacity are scarce. A strength test protocol was administered to collect data on static one-handed pulling strength using four handle heights and three pulling directions: across (handle opposite to the pulling hand), front, and side (handle on the same side of the pulling hand). Eighty-six participants (46 men and 40 women) in five age groups completed the protocol. The results showed that pulling from the side of the body resulted in the greatest strength, followed by front and across pulls. As the handle height increased from 61 cm above the floor, to above the shoulder, the pulling strength decreased. This dataset provides occupational safety and ergonomics professionals gender specific normative data on one-handed pull strength capacity in different age groups., (Copyright © 2012 Elsevier Ltd and The Ergonomics Society. All rights reserved.)

The primary objectives of this study were to describe and analyze the hand force exertion patterns of experienced nursing home nurses and nursing students during dynamic medicine cart pushing tasks in Initial, Sustained, Turning, and Stopping motion phases. A 2 × 2 × 2 factorial experiment was conducted with 22 participants to estimate the effects of lane congestion, precision cart control, and floor surface on horizontal hand forces. Root mean squared (RMS) lane deviation patterns were also described to provide an indicator of cart handling difficulty across the different study conditions. Descriptive statistics revealed that nurses exerted greater mean hand force (10%) and made more (12%) lane deviation than students and that the highest two-hand forces of 147N were measured in the Turning phase on carpet. Strong correlations between work experience group, body mass, and BMI required that force data for nurses and students be collapsed in analytical models where no group differences existed. Predicted pushing forces on carpeted floor surface were significantly greater than on tile in Initial (14N), Sustained (14N) and Turning (18N), except in stopping where pulling forces were 37N lower. High lane congestion predicted significant peak force increases of 4N and 7N in Sustained and Turning, respectively, but decreased by 20N in Initial. High precision control led to significant decreases in two-hand forces that ranged from 4 to 20N across motion phases. Complex interactions among the experimental factors suggest that work environment (lane congestion and floor surface) and work demands (precision control) should be included in the evaluation of pushing tasks and considered prior to making renovations to nursing home environments., (Copyright © 2012. Published by Elsevier Ltd.)

Hand-handle interface is seldom considered in contemporary upper limb biomechanical analyses of pushing and pulling strength. A laboratory study was designed to examine if handle rotation in the frontal plane (0°-horizontal, 45°, and 90°-vertical), anterior tilt (0°-parallel to the frontal plane, and 15°), and distance between two handles (31 and 48.6 cm) affect pushing strength and subjective rating of handle preference. A special testing station was constructed to elicit upper limb push exertions that involved minimal contribution of the torso and legs. Within the station, four load cells were used to measure the horizontal (forward pushing) and vertical components of the pushing forces. Thirty-one participants performed seated bi-manual pushing strength tests. Comparing to the reference handle configuration (horizontal, straight, and a 31-cm between-handle distance), the 45°-rotated and tilted handles with a 31-cm between-handle distance allowed 6.7% more pushing output, while the horizontal and tilted handles with a 31-cm between-handle distance resulted in 2.8% less. Subjective preference was correlated with normalized pushing strength (r=0.89). Tilted handles, at 45°-rotated and vertical positions received highest subjective ratings of preference among all handle configurations. Men exerted greater pushing strength with the 48.6-cm handle distance while women's capacity was greatest with the 31-cm distance. The results demonstrated that handle rotation and tilt angles affected pushing strength and should be taken into consideration when evaluating or designing pushing tasks., (Copyright © 2011 Elsevier Ltd and The Ergonomics Society. All rights reserved.)

Powered hand tools have the potential to produce reaction forces that may be associated with upper extremity musculoskeletal disorders. In this study, subjective ratings of discomfort and acceptability of reaction forces were collected in an attempt to identify their associations with factors such as work location, and response covariates such as grip force and tool handle displacement. Three work configurations using pistol grip and right angle pneumatic nutrunners on horizontal and vertical surfaces were set up in the laboratory. Twenty healthy right-handed male participants operated four tools at nine locations and the corresponding subjective responses were collected. The results indicate that normalized grip force during the torque buildup period was a significant factor for both subjective ratings. For the unacceptable torque reactions across the three tool configurations, the ratio of hand moment impulse over tool torque impulse was significantly greater than for the acceptable reactions. For pistol grip tools used on the vertical surface, as the working height increased 30 cm, the odds of an unacceptable rating over an acceptable rating increased 1.6 times. Prediction models for subjective ratings of discomfort and acceptability provide insight regarding either workstation design or exposure control. These models can further be used to establish exposure limits based on handle displacement and grip force.

The objective of this study is to investigate the workstation and tool effects on the responses of the powered hand tool operator reacting against the impulsive reaction forces that may be associated with upper extremity musculoskeletal disorders. The study demonstrated a means of direct measurement of force at the interface between the tool and the operator. Fifteen experienced male operators performed three independent work configurations: pistol grip and right angle tools used on the horizontal surface and pistol grip tools used on the vertical surface, in the laboratory. A full factorial experiment consisting of 36 conditions was designed to examine the effects of working height, distance, tool, and fastener joint hardness on handle displacement and grip forces. The results indicate that operator responses were affected by different factors depending on the work configuration. When pistol grip tools were used on the vertical surface, the mean handle displacement decreased from 9.9 degrees to 7.3 degrees as the working height increased from 30 cm below shoulder to 30 cm above shoulder. When right angle tools were used, the greatest handle displacement (51.1mm) and grip force (84.7% MVC) during torque reactions were measured at 30 cm below elbow and 40% forward reach away from the operator. This study provides quantitative information that can be used for workstation design and tool selection to reduce the torque reaction experienced by powered nutrunner operators.