ABSTRACT
Sit-stand desks are popular however many people have standing-induced low back pain (LBP). People with LBP have fewer standing weight shifts compared with back-healthy people. Participants were classified as standing-tolerant or intolerant. Participants were provided sit-stand desks for 12 weeks. Participants were assigned to intervention (graded standing exposure and exercise) or control (no instruction) conditions. Participants reported weekly sitting time and average/worst LBP. Standing weight shifts and LBP were re-assessed post-intervention. All groups decreased sitting time (range: 30-50%) over 12 weeks. Sitting time and average LBP were correlated in all standing-intolerant individuals, worst LBP and sitting time were correlated for intervention group only. All standing-intolerant individuals increased standing weight shifts and decreased LBP after 12-weeks. Standing-intolerant individuals benefitted from 12-weeks of sit-stand desk use regardless of intervention. Motivated individuals with standing-induced LBP may increase standing tolerance with sit-stand desk use. Additional benefits may exist when structured guidance is provided. Practitioner summary: Many people are standing-intolerant due to low back pain (LBP). This lab and field-based study showed some benefits from structured approaches to gradually progress standing time when transitioning to standing work. Using a sit-stand desk for 12 weeks resulted in decreased LBP and sitting time in standing-intolerant people. Abbreviations: LBP: low back pain; OSPAQ: Occupational Sitting and Physical Activity Questionnaire; VAS: visual analog scale; GRF: ground reaction force; WeekVASMAX: worst low back pain reported on visual analog scale for prior week; WeekVASAVE: average low back pain reported on visual analog scale for prior week; ICC: intraclass correlation coefficient; LabVASMAX: worst low back pain reported on visual analog scale during lab-based standing; LabVASAVE: average low back pain reported on visual analog scale during lab-based standing; FvR,L: vertical ground reaction force for right and left force plate; BWSSMALL: small (10-29% body weight) body weight shift; BWSLARGE: large (> 30% body weight) body weight shift; ActivPALSED: ActivePAL data for sedentary time; ActivPALSTND: ActivePAL data for standing time; ANOVA: analysis of variance; Standing Intolerant-INT: standing intolerant participants assigned to intervention condition; Standing Intolerant-CON: standing intolerant participants assigned to control condition; Standing Tolerant-INT: standing tolerant participants assigned to intervention condition; Standing Tolerant-CON: standing tolerant participants assigned to control condition; SI: standing intolerant; ST: standing tolerant; INT: intervention; CON: control.
Subject(s)
Ergonomics/instrumentation , Low Back Pain/physiopathology , Occupational Diseases/physiopathology , Posture , Standing Position , Adult , Female , Humans , Interior Design and Furnishings , Male , Middle Aged , Pain Measurement , Time Factors , Young AdultABSTRACT
Occupational standing is associated with musculoskeletal and venous disorders. The aim was to investigate whether lower leg oedema and muscle fatigue development differ between standing and walking and whether age, gender and standing work habituation are factors to consider. Sixty participants (15 young females, 15 young males, 15 older males, and 15 young males habituated to standing work) were included and required to stand/walk for 4.5 hours in three periods with two seated breaks. Waterplethysmography/bioelectrical impedance, muscle twitch force and surface electromyography were used to assess lower leg swelling (LLS) and muscle fatigue as well as gastrocnemius muscle activity, respectively. While standing led to LLS and muscle fatigue, walking did not. Low-level medial gastrocnemius activity was not continuous during standing. No significant influence of age, gender and standing habituation was observed. Walking can be an effective prevention measure to counteract the detrimental effects of quasi-static standing.Practitioner summary: Prolonged standing leads to lower leg oedema and muscle fatigue while walking does not. The primary cause of fatigue may be in other muscles than the medial gastrocnemius. Walking may be an effective prevention measure for health risks of occupational standing when included intermittently.Abbreviation: BI: bioelectrical impedance; LLS: lower leg swelling; SEMG: surface electromyography; MTF: muscle twitch force; WP: waterplethysmography; Bsl: Baseline; L: Lunch; E: Evening; MTM: method times measurement; EA: electrical activity; IQR: interquartile range; p: percentile; M: mean; SE: standard error; Adj: adjusted.
Subject(s)
Edema/physiopathology , Muscle Fatigue , Occupational Diseases , Standing Position , Walking , Adolescent , Adult , Age Factors , Aged , Electric Impedance , Electromyography , Female , Humans , Male , Middle Aged , Muscle, Skeletal/physiopathology , Sex Factors , Young AdultABSTRACT
This study aims to investigate the cross-sectional association between objectively measured total time and temporal patterns of static standing (short bouts: 0-5 min; moderate bouts: >5-10 min; and long bouts: >10 min) during work and leisure and low back pain (LBP) among 698 blue-collar workers. Workers reported LBP on a 0-10 scale. The association between time spent on static standing and LBP was tested with linear regression. A positive association with LBP intensity was found for long bouts of static standing (ß = 0.27) during total day (work + leisure), and total static standing time at leisure (ß = 0.12). No significant associations were found for static standing during work and LBP intensity. These findings indicate that particularly long bouts of static standing over the entire day contribute to LBP in blue-collar workers. Practitioner Summary: The association between LBP and static standing time was investigated. This study indicates that prolonged time standing during total day and standing during leisure are positively associated with LBP among blue-collar workers. Therefore, practitioners should consider long periods of standing as a potential risk factor for LBP.
Subject(s)
Low Back Pain/etiology , Occupational Diseases/etiology , Standing Position , Accelerometry , Adult , Cross-Sectional Studies , Denmark , Female , Household Work , Humans , Linear Models , Male , Manufacturing and Industrial Facilities , Middle Aged , Occupations , Risk Factors , Sex Distribution , Surveys and Questionnaires , TransportationABSTRACT
BACKGROUND: Few studies have reported the contribution of correction of leg length discrepancy (LLD) on the kinematic and kinetic characteristics of the pelvis and hip joints among those who must stand while working using shoe insoles and a three-dimensional (3D) motion analysis system. OBJECTIVE: To investigate dynamic pelvic and hip joint angles and hip moments using a 3D motion analysis system with and without insoles in standing workers with LLD. METHODS: Kinematic and kinetic data of 31 participants with LLD were collected using a motion analysis system and force platforms. Participants were asked to walk wearing standard shoes or shoes with LLD-corrected insoles. Repeated-measures analysis of variance (ANOVA) was used to compare the kinematic and kinetic data of the hip joints and pelvic orientation according to leg side and corrective interventions for LLD. RESULTS: There were significant differences in maximal ROM of hip adduction and abduction with vs. without LLD insoles in the longer and shorter legs (pâ<â0.05). There were significant differences in maximal elevation (pâ=â0.004) and total coronal motion (pâ=â0.006) of the pelvic segment with and without insole corrections in the longer leg during gait. CONCLUSIONS: LLD correction using a customized insole is a recommended therapeutic intervention to improve the musculoskeletal imbalances of hip and pelvic segments in workers with LLD.
Subject(s)
Leg Length Inequality , Leg , Biomechanical Phenomena , Gait , Hip Joint , Humans , Leg Length Inequality/complications , Leg Length Inequality/therapy , PelvisABSTRACT
OCCUPATIONAL APPLICATIONSIn this paper, we provide a framework for practitioners when (re)designing tasks that historically have required standing in the workplace. While the goal is not to remove standing from all jobs, practitioners must work with management to align health and safety outcomes related to standing at work with the enterprise's main outcomes. Practitioners should also be made aware that in many of these jobs, standing has been required because, in the enterprise's judgment, it improves performance and customer service. Understanding common beliefs about customer interactions and job performance in the workplace will be vital to implementing changes that have previously been difficult to navigate.
Background: Modern office workplaces promote standing to reduce occupational sitting time; however, workers have advocated for reducing occupational standing in the retail and service industries.Purpose: To create a conceptual framework for practitioners and researchers to use when examining the use of suitable seating in the workplace compared to standing.Methods: An inductive content analysis was used to analyze class-action lawsuits filed in California related to "suitable seating." Themes were extracted and organized based on our conceptual model.Results: Justification for standing or the use of suitable seating was based on organizational policies and practices, requirements of the condition of work, health and safety, and enterprise outcomes.Conclusions: Practitioners and researchers should be aware of the business justification for standing in the workplace and the firmly held beliefs about customer service and performance implications. Future work must determine if adverse health and well-being outcomes from workplace standing negate the perceived benefits of standing.
Subject(s)
Occupations , Standing Position , Workplace , California/epidemiology , MotivationABSTRACT
PURPOSE: Nonlinear analysis techniques provide a powerful approach to explore dynamics of posture-related time-varying signals. The aim of this study was to investigate the fundamental interactions between postural variability structure and discomfort development during prolonged standing. METHODS: Twenty participants, with equal distribution for gender and standing work experience (SWE), completed a simulated long-term standing test. Low back and legs discomfort, center of pressure, lumbar curvature, and EMG activity of trunk and leg muscles were monitored. Nonlinear measures including largest lyapunov exponent, multi-scale entropy, and detrended fluctuation analysis were applied to characterize the variability structure (i.e., complexity) in each signal. The size (i.e., amount) of variability was also computed using traditional linear metrics. RESULTS: With progress of low back and legs discomfort over standing periods, significant lower levels were perceived by the participants having SWE. The amount of variability in all signals (except external oblique EMG activity) were significantly increased with the time progress for all participants. The structure of variability in most signals demonstrated a lower complexity (more regularity) with fractal properties that deviated from 1/f noise. The SWE group showed a higher complexity levels. CONCLUSIONS: Overall, the findings verified variations in structure and amount of the postural variability. However, nonlinear analysis identified postural strategies according to the perceived discomfort in a different way. These results provide supports for future application of nonlinear tools in evaluating standing tasks and related ergonomics interventions as it allows further insight into how discomfort development impact the structure of postural changes.
Subject(s)
Posture , Standing Position , Entropy , Ergonomics , Humans , Postural Balance , TorsoABSTRACT
BACKGROUND: The prolonged standing position is an important factor in the onset of foot musculoskeletal disorders among workers. Safety shoes, designed to protect against the physical constraints of the work environment, do not address this issue to date. OBJECTIVES: The goal of this study is to assess the possible benefits of custom-made foot orthoses among prolonged standing workers. STUDY DESIGN: repeated measures without control group. METHODS: Thirty-four standing workers who suffer from foot pain volunteered for the study. Custom-made foot orthoses, designed by a podiatrist, were 3D-printed and distributed to each volunteer. Static balance as well as static and dynamic plantar pressure measurements were carried out with sensors inserted in the safety shoes, before and after three weeks of wearing foot orthoses daily. A questionnaire on pain and comfort was also distributed before and after treatment. RESULTS: Feelings of pain, discomfort and heavy legs were found to be significantly reduced after wearing 3D-printed orthoses (p<0.05). Additionally, in static and dynamic conditions, a significant decrease in mean peak pressure in the rearfoot area was observed along with a significant increase in mean peak pressure in the midfoot area (p<0.05). There was also a significant improvement of balance in the medial-lateral direction. CONCLUSION: Custom-made orthoses significantly increase the well-being of standing workers in our experimental testing conditions. The custom-made shape allows for a better balanced distribution of foot peak pressure thanks to its support and stimulation of the foot arches particularly through a shift of pressure from the heel to the midfoot.
Subject(s)
Foot Diseases/rehabilitation , Foot Orthoses , Occupational Diseases/rehabilitation , Patient Acceptance of Health Care/psychology , Standing Position , Adult , Equipment Design , Female , Foot/physiopathology , Foot Diseases/etiology , Foot Diseases/psychology , Humans , Male , Occupational Diseases/etiology , Occupational Diseases/psychology , Work/physiologyABSTRACT
The main objective of the study is to determine the noise level emitted by the machinery and equipment used at a Liquefied Petroleum Gas in Melaka, Malaysia. The study also aims to determine the exposure level of noise to the employees. The machinery and equipment noise level was measured using a calibrated sound level meter. Noise level of each source was measured by pointing the sound level meter microphone at normal working distance to the source. Personal noise exposure was conducted at the shoulder of the personnel and as close as possible to the personnel’s ear. From a total of 154 noise sources points identified at three work areas surveyed, 122 points were above Action Level of 85 dBA of which 57 points had exceeded the Permissible Exposure Limit of 90 dBA. For the personal exposure monitoring, ten out of fourteen had exceeded the Action Level of 85 dBA for those working for 8 hours and 82 dBA for those working for twelve hours and one of them had exceeded the Permissible Exposure Limit of 87 dBA for those working for twelve hours. The monitored personnel have exceeded the Maximum Level and the Peak Level limit of 115 dBA and 140 dB respectively. From the study, it is concluded that further noise monitoring is needed especially when there are changes to the work process and equipment used. Also the requirement to notify the selected workers on the personal noise exposure result, actions to reduce noise level at the workplace through engineering control methods and administrative controls.
ABSTRACT
@#In order to accomplish a wide range of duties and responsibilities that may be done under unpleasant working conditions, prolonged standing posture is common with school teachers. Nevertheless, standing upright for a long time or otherwise regarded as prolonged standing frequently contributes to body pain and discomfort, muscle fatigue and even health problems such as musculoskeletal disorders (MSDs). The aim of this paper is to review MSDs arising from prolonged standing and spread information on existing ergonomic and non-ergonomic interventions to alleviate prolonged standing discomfort. Systematic review on prolonged standing school teachers with specific keywords were recognized to discover the appropriate studies and information in a systematic search. The informations in this review may be helpful to guide teacher, school management and researchers to implement the suitable interventions in order to minimise the health issue due to MSDs among school teachers.