Levels Of Physical Demands Research Articles

Sports-related wrist and hand injuries: a review

BackgroundHand and wrist injuries are common during athletics and can have a significant impact especially if initially disregarded. Due to their high level of physical demand, athletes represent a unique subset of the population.Main bodyThe following is an overview of hand and wrist injuries commonly seen in athletics. Information regarding evaluation, diagnosis, conservative measures, and surgical treatment are provided.ConclusionKnowledge of these entities and special consideration for the athlete can help the team physician effectively treat these players and help them achieve their goals.

Job stress dimension and work-related musculoskeletal disorders among southeast Nigerian physiotherapists

Background. Although publications describe physical demands of the job in the physiotherapy profession, there is a dearth of literature on job stress dimensions (JSDs), and their relationship to work-related musculoskeletal disorders (WMSDs). Objective. To investigate JSDs and their relationship to WMSDs among physiotherapists currently practicing in southeast Nigeria. Method. A cross-sectional study using items related to the Job Content Questionnaire and the Nordic musculoskeletal questionnaire. Data were summarized with descriptive statistics, and the relationship between WMSDs and JSDs was analyzed with the Mann–Whitney U test. Results. A total of 126 physiotherapists responded. There were high levels of stress in most of the job dimensions investigated: 82.1% and 22.8% of the physiotherapists had WMSDs in at least one body region in the last 12 months and the last 7 days respectively. The lower back was the most commonly affected in both periods. No specific domain was related to development of WMSDs. Conclusion. Over 80% of physiotherapists in southeast Nigeria have WMSDs. However, despite high levels of physical demands on the job, physiotherapists have job control and good social support. Intervention programs aimed at reducing WMSDs in physiotherapists should focus on risk factors that target the physical demands of the job.

History Dependency of Muscle Strength Recovery from a Fatiguing Intermittent Task

Muscle fatigue and recovery are complex processes influencing muscle force generation capacity. While fatigue reduces this capacity, muscle recovery acts to restore the unfatigued muscle state. Many factors can potentially affect muscle recovery, among these may be a task dependency of recovery following an exercise. However, little has been reported regarding the history dependency of recovery after fatiguing contractions. Recently, we investigated the dependency of the fatigue process on cycle time during low to moderate exertion levels of intermittent muscle contraction (Rashedi & Nussbaum, 2016). A dependency of localized muscle fatigue on cycle time was shown, even though there was a consistent level of overall physical demand. It was concluded that the difference in fatigue development might be related to recovery processes occurring during execution of the intermittent task. In the present study, we focused on the potential effect of contraction history on post-fatigue recovery. Based on the expected dependency of recovery to task demands during exercise, it was hypothesized that post-fatigue recovery will also be affected by the history of exercise-induced muscle fatigue. We examined the dependency of muscle recovery subsequent to four different histories of fatiguing muscle contractions, imposed using two cycle times (30 and 60 sec) during low to moderate levels (15% and 25% of maximum voluntary contraction (MVC)) of intermittent static exertions involving index finger abduction. All participants completed the intermittent contractions, in all four conditions, for 1 hour, and MVCs were obtained at fixed intervals during 1 hour of post-exercise recovery (i.e., at 0.2, 5, 10, 30, and 60 minutes). There was a clear and statistically-significant dependency of muscle recovery rate on the muscle capacity state existing immediately after fatiguing exercise. This dependency did not appear to be modified by either the cycle time or exertion level leading to that state. Similar results were found in the study of Iguchi et al. (2008), wherein the authors compared recovery between two different exertion histories while fatiguing muscles to the same level, though recovery was only monitored for 5 minutes. These results imply that the post-exercise rate of recovery is primarily influenced by the post-exercise muscle state. Such evidence may help improve existing models of muscle recovery (Rashedi & Nussbaum, 2015b), facilitating more accurate predictions of localized muscle fatigue development (Rashedi & Nussbaum, 2015a), and thereby helping to enhance muscle performance and reduce the risk of injury

Relationship Between External and Internal Loads of Professional Soccer Players During Full Matches in Official Games Using Global Positioning Systems and Heart-Rate Technology

To analyze the match running profile, distance traveled over successive 15 min of match play, heart rates (HRs), and index of performance efficiency (effindex) of professional soccer players with a global positioning system (GPS) and HR in official competition. Twenty-six professional players were investigated during full matches in competitive club-level matches (N = 223). Time-motion data and HR were collected using GPS and HR technology. The relative total distance was 113 ± 11 m/min, with substantial differences between halves. For all playing positions, a substantial decrease in total distance and distance covered at >13.0 km/h was observed in the second half in comparison with the first. The decrease during the second half in distance covered at >13.0 km/h was substantially higher than in total distance. The average HR recorded was 86.0% maximal HR, and the relationship between external and internal load (effindex) was 1.3, with substantial differences between halves in all playing positions, except strikers for effindex. Wide midfielders reflected substantially the lowest mean HR and highest effindex, whereas center backs showed substantially the lowest effindex of all playing positions. The current study confirmed the decrement in a player's performance toward the end of a match in all playing positions. Wide midfielders displayed the highest and fittest levels of physical and physiological demands, respectively, whereas center backs had the lowest and least-fit levels of physical and physiological demands, respectively. The position-specific relationship between external and internal load confirms that players with more overall running performance during the full match were the best in effindex.

Descriptive Analysis of Cardiovascular Demands During Elite Curling

Heart rate (HR) response has been shown to effectively reflect metabolic expenditure during physical activity. While HR response has been heavily studied during athletic events such as soccer and running, there has been little research conducted on the physiological responses, such as HR variability, of athletes while participating in the sport of curling. PURPOSE: The aim of exploratory study was to establish the HR response in elite curling athletes and examine how various positions and their physiological demands influence HR in a curling match. METHODS: HR was continuously collected on three elite male curlers during one match of an elite level competition.The match lasted approximately 120 minutes and consisted of each player rotating through three specific positions: house, sweeping, and throwing. HR data was collected using heart rate monitors specifically designed for team use and was analyzed using SPSS software. RESULTS: HR ranges were 61-192 bpm while in the house position, 110-207 bpm in the sweeping position and 86-203 bpm for when in the throwing position. The mean HR was 91 +/- 31 bpm for the house position, 151+/- 22 bpm for the sweeping position and 120 +/- 27 bpm for the throwing position. CONCLUSION: This exploratory study indicates a high level of physical and cardiovascular demand in elite curling athletes, which has has not been established previously, thus reflecting a high level of metabolic expenditure. These data suggest implications for metabolic expenditures in curling that may be similar to the metabolic demand in other sports requiring high intensity efforts.

Mental and Physical Symptoms of Female Rural Workers: Relation between Household and Rural Work.

This study aimed to investigate the relations among mental disorders, physical discomfort, household work and farm work among women. We conducted a cross-sectional study based on the administration of a structured questionnaire to 182 female farm workers. The data were analyzed by means of Poisson regression, where the significance level was set to 5%. Results indicated that 111 (61%) participants reported work-related mental disorders and physical discomfort was reported by 160 (87.9%). The participants with mental disorders and at least moderate levels of physical discomfort reported significantly higher levels of physical demand, time working (temporal demand), total effort and frustration with regard to farm work, in addition to significantly higher levels of frustration with regard to housework. Women with moderate or greater levels of both physical discomfort and frustration with farm work increased the chances of mental disorders. The results illustrate the complex challenge for health professionals in caring for women with mental disorders and physical discomforts related to their farm work, in the context of both the farm and domestic work demands these workers experience.

Occupational physical demand and risk of hip fracture in older women

ObjectivesHip fractures are leading causes of disability, morbidity and mortality among older women. Since physical activity helps maintain physical functioning and bone mineral density, occupational physical demand may influence fracture...

Occupation and other risk factors for injury among enlisted U.S. Army Soldiers

ObjectiveTo investigate injury risk associated with occupation and occupational physical demand levels among U.S. Army Soldiers. Study designRetrospective cohort study. MethodsPersonal characteristics, physical fitness, military occupational specialty (MOS), and injury data were obtained by survey from Soldiers in an Army light infantry brigade (n = 2101). Odds ratios (OR) and 95% confidence intervals (95% CI) from a multivariate analysis assessing injury risk were calculated. ResultsInjury incidence for the prior 12 months was 43%. Physical fitness and behavioral factors associated with injury risk included age 21–29 (OR [age 21–29/age ≤ 20] = 1.37, 95% CI 1.00–1.90), BMI 27.5–29.9 (high-overweight) (OR high-overweight/normal = 1.62, 95% CI 1.20–2.18); BMI >29.9 (obese) (OR obese/normal = 1.73, 95% CI 1.23–2.44), cigarette smoking (OR Smoker/Nonsmoker = 1.34, 95% CI 1.11–1.63), and poor APFT two mile run performance (OR (Q4/Q1) = 1.61, 95% CI 1.19–2.19). Higher risk of injury was associated with some MOSs (OR (Chemical, Explosives & Ammunition/Infantry) = 2.82, 95% CI 1.19–6.68; OR (Armor/Infantry) = 1.53, 95% CI 1.13–2.07). ConclusionThis study identified a number of potentially modifiable risk factors for injuries including: maintenance of healthy weight, improved aerobic endurance, and reduction in smoking. Results also indicate certain Army occupations may be at higher risk of injury. Further investigation into reasons for their higher risk is warranted.

An Exploratory Study of the Effects of Occupational Exposure to Physical Demands on Biomarkers of Cartilage and Muscle Damage

Biomarkers of tissue damage, derived from tissues commonly injured as a result of occupational physical demands, may be of use for future prediction of work-related musculoskeletal disorders (WMSDs). This exploratory study assessed whether selected biomarkers are likely to be sensitive to the level of occupational physical demands. Twenty-four participants were recruited to form two groups, with relatively high and low levels of WMSD risk. Serum levels of Cartilage Oligomeric Matrix Protein (COMP), Interleukin-6 (IL6), and Creatine Kinase (CK)—which respectively indicate cartilage damage, muscle use, and muscle damage—were obtained,. Six blood samples were obtained before and after work on Monday, Wednesday, and Friday of one working week. Additionally, a self-report measure of risk factor exposure, the Hollmann Index, was used to, and did, confirm group differences in WMSD risk. COMP levels varied significantly over time, but not between groups. IL6 levels were greater in the high-risk group at all time points and varied significantly over time and between groups. CK levels did not vary significantly over time or between groups. IL6 successfully differentiated between the high and low risk groups, suggesting potential use in the occupational domain. Prospective studies are needed, though, to associate biomarker levels/changes with WMSD risk.

Improved Functional Capacity Evaluation Performance Predicts Successful Return to Work One Year After Completing a Functional Restoration Rehabilitation Program

ObjectiveTo evaluate whether functional capacity evaluation (FCE) scores are responsive to functional restoration treatment, and to assess the ability of FCEs at program discharge to predict work outcomes. DesignAn interdisciplinary cohort study of prospectively collected data. SettingA functional restoration center. PatientsA consecutive sample of 354 patients with chronic disabling occupational musculoskeletal disorders (CDOMDs) completed a functional restoration program consisting of quantitatively directed exercise progression and multi-modal disability management with interdisciplinary medical supervision. MethodsEach patient participated in an FCE at admission and discharge from treatment. The results of each FCE yielded the physical demand level (PDL) at which patients were functioning. Patients were initially divided into 5 PDL groups, based on job-of-injury lifting, carrying, and pushing/pulling requirements, for the pre- to posttreatment responsiveness analyses. Patients were subsequently divided into 5 PDL groups, based on their performance on the FCE upon program completion. Main Outcome MeasuresOutcome measures included admission-to-discharge changes in PDLs and 2 specific FCE lifting tasks: isokinetic lifting; and the Progressive Isoinertial Lifting Evaluation (PILE). Socioeconomic outcomes were also evaluated, including post-discharge work return and work retention 1-year after treatment completion. ResultsOverall, 96% of the patients demonstrated improvement in their PDLs from admission to discharge. A majority of patients (56%) were able to achieve a discharge PDL that was comparable to their estimated job-of-injury lifting requirement or higher (P < .001). Lifting ability improved from admission to discharge by approximately 50% (all P < .001). Discharge PDLs predicted both work return (P < .001) and work retention (P < .001) 1 year later. ConclusionsFCE scores were responsive to functional restoration treatment, and the associated discharge PDLs predicted work return after treatment completion and work retention 1 year later.

Paraspinal Muscle Morphology and Composition

The purposes of this study were to define the natural progression of age-related changes of the lumbar paraspinal muscles during adulthood and to investigate the influence of lifestyle and individual factors (e.g., physical activity levels at work and leisure, body mass index, and low back pain [LBP]). This population-based longitudinal study included a sample of 99 adult male twins. Data were collected through a structured interview, physical examination, and magnetic resonance imaging. Measurements of the lumbar multifidus and erector spinae muscles were obtained from T2-weighted axial images at L3-L4 and L5-S1 at baseline and 15-yr follow-up. Muscle cross-sectional area (CSA), functional CSA (FCSA) (fat-free mass), and FCSA/CSA (composition) as well as CSA and FCSA asymmetry and FCSA/CSA side-to-side differences were measured. Subjects' mean ± SD age was 47.3 ± 7.4 yr at baseline and 62.3 ± 8.0 yr at follow-up. During the 15-yr period, both muscles exhibited a decrease in CSA and FCSA and an increase in fatty infiltration and side-to-side differences in size and composition at both spinal levels. Both muscles displayed greater changes at L5-S1 than L3-L4. Age and BMI were found to be significantly associated with the degree of paraspinal muscle changes over time. However, there was no association between the change in paraspinal muscle size, composition, or asymmetry with the level of physical demands at work or leisure or LBP history. The present longitudinal study suggests that over adulthood, the multifidus and erector spinae undergo similar morphological changes. Moreover, our findings suggest that the long-term progression of lumbar paraspinal muscle changes evaluated through magnetic resonance imaging are not associated with the range of physical demand levels as were typical of Finnish men or LBP history.

Evaluation of hydraulic excavator Human–Machine Interface concepts using NASA TLX

This study evaluated newly proposed Human–Machine Interface (HMI) design concepts for improving the ergonomics of hydraulic excavators. The design concepts were based on an augmented interaction technique which involved the use of heads-up display (HUD) and coordinated control as HMI elements. Two alternative HMI designs were elaborated in order to separately evaluate the ergonomic impacts of the head-up display and the coordinated control by comparing them to the standard HMI design. The effectiveness of these three HMI designs in terms of the reduction of the operators' mental and physical workload were assessed by conducting experiments utilizing human subjects, ages 23–35 years. The National Aeronautics and Space Administration's Task Load Index (NASA TLX) method was used for collecting subjective workload scores based on a weighted average of ratings of six factors: Mental Demand, Physical Demand, Temporal Demand, Own Performance, Effort, and Frustration Level. The results showed that the type of HMI design affects different aspects of the operator's workload. Indeed, it showed how the proposed augmented interaction is an effective solution for reducing the ergonomic gaps in terms of mental workload, and to a lesser extent the physical workload, subjected by the standard HMI design. Relevance to industryThis study proposes innovative HMI solutions featuring heads-up display and coordinated control to improve the ergonomics of the hydraulic excavator HMI, particularly in reducing the operators' mental and physical workload. The results of this study promises to be an innovative approach for developing new HMI designs by hydraulic excavator manufacturers.

Using qualitative research within complex interventions: lessons from the podosa (prevention of diabetes and obesity in South Asians) trial

Findings Many participants were aware of their family history of diabetes and attracted by the availability of information and monitoring. Offering home or clinic-based interventions, communication in the participant’s chosen language(s) and excellent relationships between participants and dieticians contributed to retention. Adaptations in food choices were accommodated by participants, although community and faith based considerations made consistent adherence challenging. Participants found increasing their level of physical activity difficult given other demands, including long working hours, physically demanding employment and domestic commitments.

A Comparison of Deployed Occupational Tasks Performed by Different Types of Military Battalions and Resulting Low Back Pain

With deployment Soldiers must now wear body armor and additional equipment while performing occupational tasks, representing a large demand that has not been considered when studying military occupations. The purpose of this study was to: (1) describe tasks required by different occupational battalions within a Brigade Combat Team; (2) establish the incidence of low back pain (LBP) in each battalion and; (3) determine which tasks predict LBP within the different battalions. This was a prospective cohort study investigating 805 Soldiers in a Brigade Combat Team deployed to Afghanistan for 1 year. Demographic, occupational, and fitness variables were recorded. There was no difference in time spent on fitness training between the battalions. Occupational tasks performed by deployed Soldiers vary in the level of physical demand between battalions. Infantry had the highest fitness score (257); wore the heaviest equipment (70 lb.); spent the most time wearing body armor (49 hours/week), performing dismounted patrol (29 hours/week), and lifting objects (35 hours/week); spent the least amount of time working at a desk (14 hours/week); but had a similar incidence of LBP (77%) compared to other battalions. History of LBP and time spent wearing body armor were the two most consistent predictors of LBP across battalion types.

Associations of occupational attributes and excessive drinking

Numerous work-related drinking mechanisms have been posited and, oftentimes, examined in isolation. We combined data from over 100 occupational attributes into several factors and tested the association of these factors with measures of alcohol use. We used the NLSY79 2006 wave, a U.S. representative sample of 6426 workers ages 41 to 49 and the 2006 Occupational Information Network database (O*NET), a nationally representative sample of nearly 1000 occupations. We conducted exploratory factor analysis on 119 occupational attributes and found three independent workplace characteristics – physical demands, job autonomy, and social engagement – explained the majority of the variation. We then tested the association of these composite attributes with three drinking measures, before and after adjusting for gender, race/ethnicity, and a measure of human capital using count data models. We then stratified by gender and repeated our analyses. Men working in occupations with a one standard deviation higher level of physical demand (e.g. construction) reported a higher number of heavy drinking occasions (+20%, p < 0.05). Job autonomy was not significantly associated with measures of alcohol use and when the combined association of higher levels of physical demand and lower levels of job autonomy was examined, modest support for job strain as a mechanism for work-related alcohol consumption was found. In our pooled sample, working in occupations with one standard deviation higher levels of social engagement was associated with lower numbers of drinking days (−9%, p < 0.05) after adjustment. Physical demand and social engagement were associated with alcohol consumption measures but these relationships varied by workers' gender. Future areas of research should include confirmatory analyses using other waves of O*Net data and replicating the current analysis in other samples of workers. If our results are validated, they suggest male workers in high physical demand occupations could be targets for intervention.

Association of age and physical job demands with musculoskeletal disorders in nurses

A cross-sectional study design was applied on 273 nurses to investigate associations of physical job demands, age, and musculoskeletal disorders (MSDs) in nursing. Concurrently, participants reported on various physical job demands with a standardized questionnaire for Hospital Work. As a special contribution, this investigation illustrates findings on MSDs provided by a standardized physical examination to questionnaire data. MSD located in the lower back (8.7%) had the highest frequency, followed by the neck (7.3%), the shoulders (6.9%), and the knees (2.2%). There were significant differences in the frequencies of MSD between the young/middle age-group and the old age-group in most locations, while the only significant difference between the young and the middle age-group was found for shoulder-MSD. Furthermore high levels of physical job demands increased the risk of MSD significantly (OR = 5.7, 1.55–20.96) in all age-groups. The study provides further indication for development of age-adapted preventive measures.

Exertion-Dependent Effects of Physical and Mental Workload on Physiological Outcomes and Task Performance

OCCUPATIONAL APPLICATIONS The findings from the current study illustrate the adverse effects of concurrent physical and mental demands on shoulder muscle activation. Furthermore, the results also suggest that the effects of concurrent physical and mental demands are more pronounced during static, as opposed to dynamic, exertions. As such, it is important to consider the interaction of said work parameters (i.e., force levels, mental demands, and type of exertion) when evaluating/designing tasks. Occupational tasks requiring concurrent physical and mental work should be redesigned to reduce static loading (by changing postures or providing frequent breaks). With tasks requiring static exertions, other physical parameters (such as force) should be reduced to minimize interference due to additional cognitive processing. To conclude, concurrent physical and mental demands affect muscle activation and impede worker performance; ergonomists should consider this interaction during task design/redesign, evaluations of injury risk, and potential causal models of injury development. TECHNICAL ABSTRACT Background: Static work is considered an occupational risk factor in the development of injuries, thus there is an emphasis on employing dynamic exertions to work tasks. With workers experiencing concurrent physical and mental demands in their daily jobs, it is unclear whether these exertion types affect overall task demands differentially. Objective: The aim of this study was to compare exertion-dependent physiological responses due to concurrent physical and mental workload during intermittent shoulder exertion. Methods: Twelve young participants, balanced by gender, performed intermittent static and dynamic shoulder abduction for 3 minutes at three levels of physical workload (low, moderate, and high) in the absence and presence of a mental arithmetic task. Study measures included muscle activity, muscle oxygenation, motor and mental arithmetic task performance, and subjective responses (NASA-Task Load Index and Borg CR10 Scale). Results: Static exertions and higher physical demands adversely affected physiological responses (i.e., muscle activity and oxygenation) and performance measures, and they were associated with higher levels of perceived exertion and workload. Additional mental demands negatively affected muscle activity, mental task performance, and subjective workload measures. However, these results were more pronounced during static exertions at high physical demand levels. Conclusions: Results indicated that certain job parameters (static exertions and high physical demands) are more susceptible to interference with mental demands than others (dynamic exertions and low demands). When assessing overall demands placed on workers during concurrent physical and mental work, it is important to consider the interaction of work parameters, specifically physical demand levels and exertion type, with mental demands.

Screening for Heat Stress in Workers and Athletes

Heat-related illnesses lead to almost 6000 hospital visits per year, or two emergency department visits per 100,000 visits. Heat-related illnesses are most high among men (72%) aged 15 to 19 years and are most often associated with athletic activities (1). Global climate change will continue to have an impact on heat stress in people, on animal survival, and on food availability. The World Health Organization has estimated that over the past 30 years, 150,000 lives have been lost annually due to global heat waves and climate change (2). Weather changes have a great impact on athletes and workers by slowing efficiency and decreasing productivity (3, 4). When heat waves occur, overall mortality is also affected among the old and the young, due to their increased risk of dying from cardiovascular, respiratory, cerebrovascular, and some cardiovascular diseases, such as ischemic heart disease, heart failure, and myocardial infarction (3). Despite increasing temperatures and environmental levels of carbon dioxide, one third of metropolitan areas do not have heat stress response plans (5). Cases of heat stress are handled on a case-by-case basis rather than by being addressed collectively as a public health concern. The National Institute for Occupational Safety and Health initiated heat stress criteria in 1986 and amended them in 2008 regarding worker heat stress safety (6). Few people are aware of these criteria, of the risk factors associated with a predisposition to heat stress, or of the signs or symptoms to look for that represent risk factors for heat stress. The rules and standards proposed by the Occupational Safety and Health Administration for workplace heat stress are recommendations and still not enforceable (7). Screening for heat stress susceptibility in workers and athletes is an issue in need of public health criteria with enforceable rules based on evidence-based research. Screening for heat stress risk factors should consider physical demand level; cardiovascular, pulmonary, and endocrine status; previous history of heat stress; age; diseases; and medications including illegal drug use. Such screening should be part of the recruitment of any person expected to work or play in extremely hot environmental conditions. Older people are at increased risk for cardiovascular and thermoregulatory instability. The aging American workforce, undiagnosed disease, poor hydration while working or playing, and global warming are all factors that contribute to the need to screen workers and athletes for the risk of heat stress (8). This article first reviews some physiological aspects of temperature regulation and then provides a formula for heat stress testing, discusses guidelines for screening, and reviews accommodations for those susceptible to heat stress.

Four-year injury survey in heptathlon and decathlon athletes

Summary Background Heptathlon and decathlon may pose a greater risk of injury to athletes than other track and field events due to the number and intensity of events and to the high level of physical and psychological demand. Objective To determine frequency, location and type of injuries suffered by international decathletes and heptathletes. Methods In this retrospective case-serie study, all injuries were recorded during four seasons (1994–1998) in athletes selected to compete in international heptathlon or decathlon competitions for the French national team. Results Among the 69 athletes included in this study, 39 injuries were reported in 14 heptathletes and 47 in 18 decathletes. The injury rate was 32.5 and 30.1 injuries per 100 athletes per season for heptathletes and decathletes, respectively. The majority of injuries were located on the lower extremity (77%); 41% injuries were tendon related and 23% muscle related, and were caused by overuse (49%) or acute trauma (43%). The most common diagnoses were knee tendinopathy (14%), followed by lower leg strain (13%), thigh strain (11%) and Achilles tendinopathy (11%). Conclusions Injuries are frequent in high-level heptathletes and decathletes with an injury rate slightly higher than in other track and field events.

Prevalence of low back pain and associated occupational factors among Chinese coal miners

BackgroundVery few studies have evaluated the association between occupational factors and low back pain (LBP) among miners. The epidemiological data on LBP in Chinese miners are limited. The aim of this study was to measure the prevalence of low back pain in Chinese coal miners and to investigate the role of occupational factors.MethodsA cross-sectional survey was conducted to examine 1573 coal miners in northern China. The prevalence of LBP over a 12-month period was assessed using the Nordic Musculoskeletal Questionnaire. Odds ratios were calculated to examine the association between the prevalence of LBP over a 12-month period and occupational factors using logistic regression.ResultsAmong the coal miners, 64.9% self-reported LBP in a 12-month period. Occupational factors associated with LBP were identified, including tasks with a high degree of repetitiveness (OR 1.3, 95%CI 1.0-1.6), tasks characterized by a high level of physical demand (OR 1.4, 95% CI 1.1-1.8), posture requiring extreme bending (OR 1.6, 95% CI 1.2-1.7) and insufficient recovery time (OR 1.4, 95% CI 1.0-1.8).ConclusionLow back pain is common among Chinese miners. There were strong associations with occupational factors.