Age and physical work capacity

A Detailed Analysis of Workplace Foot and Ankle Injuries

INTRODUCTION

This study analyzes the incidence rate and median workdays missed due to foot and ankle injuries across age groups, sexes, and industries.

METHODS

Workplace injury data from 2003 to 2019 were obtained using the Nonfatal Cases Involving Day Away from Work: Selected Characteristics database provided by the Bureau of Labor Statistics (BLS). The data were grouped by injury location (ie, foot, ankle), injury type (ie, fracture, sprain), and industry, and reported with injury incidence rates and median workdays missed.

RESULTS

The incidence rate of foot and ankle injuries significantly decreased from 2003 to 2019 (P < .001). With increasing age, the incidence rate of foot and ankle injuries decreased (P < .001) and median workdays missed increased (P < .001). Men had significantly higher rates of foot and ankle injuries (P < .001). Agriculture, forestry, fishing, and hunting (foot=10.23%, ankle=10.41%); construction (foot=8.14%, ankle=8.68%); and transportation and warehousing (foot=11.06%, ankle=13.80%) industries had the highest injury incidence rates. Transportation and warehousing (foot=16.8 days, ankle=16.3 days), mining (foot=44.9 days, ankle=17.1 days), and utilities (foot=26.7 days, ankle=24.4 days) industries had the highest median workdays missed.

CONCLUSION

Increased incidence and severity of workplace foot and ankle injuries are associated with male sex and heavy labor industries. Age was positively associated with severity and negatively associated with incidence of workplace ankle injuries.

LEVELS OF EVIDENCE

Level III, Retrospective cohort study.

Association between health-related physical fitness indicators and working ability: a systematic review

OBJECTIVES

Work ability (WA) reflects a balance between work demands and an individual's ability to meet them. It is influenced by several occupational and health-related factors including the individual's physical fitness (PF). Therefore, the aim of the present study was to provide an overview of the possible relationship between PF measures and the individual's WA.

METHODS

A systematic review of studies published up to December 1, 2022 and available in PubMed, Scopus, and ISI Web of Science databases, was performed. Results have been summarized according to the specific PF parameter explored.

RESULTS

The 14 reviewed studies, enrolling 47 to 1005 workers, all showed a satisfactory methodological quality. Some positive evidence emerged for a possible association between changes in aerobic capacity, walking speed, balance, flexibility, muscle strength, and WA perception. However, the limited number of studies, their cross-sectional design, the different PF performance indicators, populations, and job tasks explored prevented definite conclusions.

CONCLUSIONS

Future longitudinal studies should be planned to confirm such positive results and identify PF indicators better predictive for changes in the WA of employees engaged in specific job tasks, particularly in physically demanding activities. This may be helpful to include PF performance tests in occupational health practice as an integrated part of risk assessment and management strategies as well as in health and well-being promotion plans.

Influence of age on functional capacity and work ability in Chilean workers: a cross-sectional study

OBJECTIVE

To determine if there are differences in functional capacity and work ability between older and younger active workers in public institutions, and to relate functional capacity to work ability.

METHODS

This cross-sectional study evaluated 360 subjects from two public institutions, a university and a high-complexity regional hospital. The participants were divided into 3 age ranges 40-49, 50-59 and ≥ 60 years. The following evaluations were applied: a multidimensional assessment questionnaire, work ability and functional capacity using physical tests (strength, flexibility and balance).

RESULTS

There are no significant differences in work ability among the different age groups (P > 0.05). Significant differences were found according to age group in 30-s chair-stand test (30-s CST), 1 repetition maximum (1RM) extending the knee 90° (1RM-leg extension) and 1RM of handgrip strength (1RM-handgrip), upper body flexibility, lower body flexibility, static balance or dynamic balance (P < 0.05). Only the variables 30-s CST (rs = 0.13, P = 0.018), lower body flexibility (rs = 0.13, P = 0.012) and static balance (rs = 0.13, P = 0.012) were related to work ability.

CONCLUSIONS

There are differences in functional capacity as the workers' ages increase. By contrast, work ability does not present any differences when comparing older and younger adults. Some physical tests of the lower extremities presented a small correlation with work ability.

The influence of age on spinal and lower limb muscle activity during repetitive lifting

This study investigated the effects of age on upper erector spinae (UES), lower erector spinae (LES) and lower body (gluteus maximus; biceps femoris; and vastus lateralis) muscle activity during a repetitive lifting task. Twenty-four participants were assigned to two age groups: 'younger' (n = 12; mean age ± SD = 24.6 ± 3.6 yrs) and 'older' (n = 12; mean age = 46.5 ± 3.0 yrs). Participants lifted and lowered a box (13 kg) repetitively at a frequency of 10 lifts per minute for a maximum of 20 min. EMG signals were collected every minute and normalised to a maximum voluntary isometric contraction. A submaximal endurance test of UES and LES was used to assess fatigue. Older participants showed higher levels of UES and LES muscle activity (approximately 12-13%) throughout the task, but less fatigue compared to the younger group post-task completion. When lifting, lower-limb muscle activity was generally higher in older adults, although temporal changes were similar. While increased paraspinal muscle activity may increase the risk of back injury in older workers when repetitive lifting, younger workers may be more susceptible to fatigue-related effects. Education and training in manual materials handling should consider age-related differences when developing training programmes.

The association between low lean mass and osteoporosis increases the risk of weakness, poor physical performance and frailty in Brazilian older adults: data from SARCOS study

PURPOSE

To characterize the phenotypes of older adults with low lean mass and osteoporosis, concomitantly or isolated, in regards to poor physical performance and frailty status.

DESIGN

Cross-sectional analysis of the SARCopenia and OSteoporosis in Older Adults with Cardiovascular Diseases Study (SARCOS).

SETTING

Outpatient geriatric cardiology clinic.

PARTICIPANTS AND METHOD

385 older adults underwent DXA analysis. Low lean mass was diagnosed according to FNIH and low BMD by a T-score ≤ -2.5 SD. Subjects were grouped into: I-Low lean mass and Osteoporosis (LLMO); II-Low lean mass (LLM); III-Osteoporosis (OP), and IV-Controls. Poor physical performance was diagnosed by weakness or slow walking speed or impaired mobility. Frailty was diagnosed by CHS criteria.

RESULTS

The mean age was 78.22 ± 7.16 years. The prevalence of LLMO, LLM, and OP were 14.8%, 39.5%, and 19.2%, respectively. LLMO subjects were older, predominantly women, with a high percentage of body fat (HTBF). LLM was represented by obese men, while individuals with OP were preferably women, older and leaner. In a regression analyses, LLMO presented an OR: 6.42 (2.63‒15.65; p < 0.001) for weakness, OR: 2.55 (1.09‒5.95; p = 0.030) for impaired mobility, and OR: 14.75 (2.72‒79.94; p = 0.002) for frailty. After adjusting for HTBF, the OR for frailty, decreased to 7.25 (1.11-47.21; p = 0.038). LLM and OP were associated only with weakness with an OR: 3.06 (1.36-6.84; p = 0.006) and OR: 3.14 (1.29-7.62; p = 0.011), respectively.

CONCLUSION

In Brazilian older community-dwelling outpatient adults, the phenotype characterized by low lean mass and osteoporosis presents a higher association with impaired mobility, weakness and frailty status compared to the others phenotyeps and controls. A high percentage of body fat presents a synergistic effect with low lean mass and osteoporosis phenotype in regards to frailty.

The Influence of Age on Firefighter Combat Challenge Performance and Exercise Training Habits

Saari, AI, Renz, G, Davis, P, and Abel, MG. The influence of age on firefighter combat challenge performance and exercise training habits. J Strength Cond Res 34(9): 2500-2506, 2020-The primary purpose of this study was to compare older vs. younger physically trained structural firefighters' performance in an international firefighter physical ability competition (Scott Firefighter Combat Challenge) and their engagement in physical training. Secondarily, firefighters' perceived importance of fitness characteristics to perform occupational tasks was evaluated. Sixty-four trained male firefighters' completed a timed occupationally specific competition course and a survey to assess exercise habits and perceived importance of fitness characteristics to perform fireground tasks. Firefighters were stratified into younger (<37 years; n = 34) and older (≥37 years; n = 30) cohorts based on the sample's median age. Independent samples t-tests were used to analyze differences in outcome measures between younger and older cohorts. It took older firefighters 8.8% longer to complete the course compared with younger firefighters (p = 0.029). Both groups reported similar training frequencies of cardiovascular (CV) training (Younger: 4.1 ± 1.7 vs. Older: 3.6 ± 1.5 session·wk, p = 0.203) and strength training (Younger: 3.6 ± 1.2 vs. Older 3.2 ± 1.4 session·wk, p = 0.274). Furthermore, there was no difference in weekly training load for CV (p = 0.663) or strength training (p = 0.898) activities between the cohorts. On average, firefighters indicated that all fitness characteristics were at least somewhat important for occupational performance. Occupationally relevant competition performance among a sample of fit firefighters was lower in older firefighters compared with younger firefighters, despite similar self-reported training volume and intensity. Practitioners may expect age-related decreases in occupational performance despite performing similar amounts of physical training.

Considerations for physical employment standards in the aging workforce

BACKGROUND

If current population and health trends continue, workplace demographics will look significantly different by the turn of the century. Organizations will no longer have a steady pipeline of younger workers and will likely need to rely on older workers to remain competitive in the global marketplace. The future multi-generational workforce will bring with it the challenge of maximizing contributions from each generation whilst at the same time addressing the health, safety and wellbeing needs of all workers.

OBJECTIVE

This review provides an insight into aging and older workers, and presents recommendations to promote worker longevity.

METHODS

This narrative review draws on evidence from 108 published sources.

RESULTS

The relationship between age and work is not simple; factors including the physical nature of the job and worker's health and fitness interact with age to either increase or decrease the potential effect of age. Evidence suggests that the issues arising from an aging workforce can be managed through polices that focus on active aging through: attitude management; flexible working and the provision of occupational health.

CONCLUSION

The integration of such interventions would require company and organizational commitment from the top down with educational programs at all levels to ensure understanding and participation.

The sink or SWIM hypothesis; a roadmap from pathology to work instability

PURPOSE

Selecting the most appropriate health-related work outcome to evaluate an intervention can be fraught with difficulty. To aid clinicians in navigating this problem we have developed a model, which illustrates how pathology can affect specific measureable quantities, such as work instability.

METHODS

Using a modified-Delphi procedure, a panel of experts met initially to analyze the content of 95 health-related work outcome measures and organize the identified areas of measurement into a coherent model, complemented by a narrative review of the literature. This initial model underwent two rounds of stakeholder-based feedback, the results of which were incorporated in the final expert panel meeting to produce the States-traits Work Instability Model (SWIM).

RESULTS

The States-traits Work Instability Model (SWIM) illustrates how changes to an individual's physical and psychological states and traits might affect their work-related performance, well-being and self-efficacy. Moreover, each concept utilized in the model was specifically selected as it represents a measurable quantity, for which there are tools available.

CONCLUSION

The SWIM is arguably the first holistic model of work that is based on both the clinical realities of vocational rehabilitation, sociological research, and is born from analyzing the basis of practical measurements. Implications for Rehabilitation Work Instability   • Work instability has multiple causes many of which are amenable to intervention   • The model clarifies the measureable domains of vocational rehabilitation interventions, which is of particular benefit for services working with people with disability at work who are struggling to remain in work   • The model conceptualizes how the potential areas for intervention may be related based on evidence available in the literature.

Six-minute walk test predicts all-cause mortality and technique failure in ambulatory peritoneal dialysis patients

AIM

This study investigated the associated factors of 6-min walk test (6MWT) and its predictive value of outcome in patients undergoing peritoneal dialysis (PD).

METHODS

This is a single centre prospective observational cohort study. Stable ambulatory PD patients in our centre between 1 May 2010 and 30 April 2011 were enrolled in this study. All included subjects performed 6MWT, and 6-min walk distances (6MWDs) were recorded. Patients were divided into two groups according to 6MWD and prospectively followed up until death, cessation of PD or to the end of the study (30 September 2012).

RESULTS

A total of 145 patients were enrolled, including 63 (43%) males. Multiple stepwise regression showed that age (β = -0.295, P = 0.001), diastolic blood pressure (DBP) (β = 0.292, P = 0.001), left ventricular ejection fraction (LVEF) (β = 0.198, P = 0.019) were independently associated with lower 6MWD. By the end of the study, six (8%) patients died in long 6MWD group while 15 (20%) died in the short 6MWD group, a significantly lower patient survival was observed in short 6MWD group (Log-rank = 4.983, P = 0.026). Patients with short 6MWD also showed inferior technique survival (Log-rank = 4.838, P = 0.028). There was no significant difference in peritonitis-free survival between the two groups (Log-rank = 0.801, P = 0.371). However, more patients in short 6MWD group had been transferred to hemodialysis due to peritonitis (25% vs 4.2%, P = 0.013).

CONCLUSION

Age, diastolic blood pressure, LVEF are independent associated factors of 6MWD in patients undergoing PD. Having the advantages of easy applicability and safety, 6MWT may be proposed as an important predictor of outcome in ambulatory PD patients.

Age-related differences do affect postural kinematics and joint kinetics during repetitive lifting

BACKGROUND

Age is considered a risk factor for manual handling-related injuries and older workers incur higher injury-related costs than younger co-workers. This study investigated the differences between the kinematics and kinetics of repetitive lifting in two groups of handlers of different ages.

METHODS

Fourteen younger (mean 24.4 yr) and 14 older (mean 47.2 yr) males participated in the study. Participants repetitively lifted a box weighing 13 kg at a frequency of 10 lifts/min for a maximum of 20 min. Postural kinematics (joint and lumbosacral angles and angular velocities) and kinetics (joint moments) were measured throughout the lifting task using motion analysis and ground reaction forces. Muscle fatigue of the erector spinae was assessed using electromyography.

FINDINGS

Peak lumbosacral, trunk, hip and knee flexion angles differed significantly between age groups over the duration of the task, as did lumbosacral and trunk angular velocities. The younger group increased peak lumbar flexion by approximately 18% and approached 99% of maximum lumbosacral flexion after 20 min, whereas the older group increased lumbar flexion by 4% and approached 82% maximum flexion. The younger group had a larger increase in peak lumbosacral and trunk angular velocities during extension, which may be related to the increased back muscle fatigue observed among the younger group.

INTERPRETATION

Older participants appeared to control the detrimental effects of fatigue associated with repetitive lifting and limit lumbar spine range of motion. The higher rates of musculoskeletal injury among older workers may stem from a complex interaction of manual handling risk factors.

Are age-related differences in the consequence of work injury greater when occupational physical demands are high?

BACKGROUND

To examine if age differences in the consequences of work injury are exacerbated when occupational physical demands are higher.

METHODS

A secondary analysis of workers' compensation claims in British Columbia (N = 373,672). Regression models examined the relationship between age and health care expenditures, days of wage replacement and the occurrence of long-term-disability following a work-related injury in occupations with lower and higher physical demands. Models were adjusted for individual and injury related covariates.

RESULTS

Older age and higher occupational physical demands were associated with worse work-injury outcomes. The relationship between age and each outcome was not exacerbated when occupational physical demands were higher compared to when they were lower. Counter to our hypotheses age differences in health care expenditures were smaller among women in more demanding occupations.

CONCLUSIONS

In this study, we found no evidence that the relationship between age and the consequences of work injury is exacerbated when physical occupational demands are high.

Increase in finishers and improvement of performance of masters runners in the Marathon des Sables

Aim

The aim of the study was to examine finisher and performance trends of ultrarunners in the Marathon des Sables, the world’s largest multistage ultramarathon.

Methods

The age and running speed was analyzed for 6945 finishes of 909 women and 6036 men between 2003 and 2012 at the Marathon des Sables covering about 240 km in the Moroccan desert.

Results

The number of finishes increased significantly for both women and men from 2003–2012. The annual number of finishes increased in age groups: 30–34 years (r² = 0.50; P = 0.021), 45–49 years (r² = 0.81; P = 0.0004), and 50–54 years (r² = 0.46; P = 0.029) for women and in all age groups older than 35 years for men (35–39 years: r² = 0.64, P = 0.0054; 40–44 years: r² = 0.67, P = 0.0036; 45–49 years: r² = 0.77, P = 0.0007; 50–54 years: r² = 0.72, P = 0.0018; 55–59 years: r² = 0.42, P = 0.041; and 60–64 years: r² = 0.67, P = 0.0038). The fastest running speed was achieved by runners in the age group of 35–39 years for both sexes. The mean age of overall finishers was 41.0 ± 9.1 years for women and 41.3 ± 9.5 years for men. For men, running speed improved for athletes in the age group of 35–39 years (r² = 0.44; P = 0.036) and of 40–44 years (r² = 0.51; P = 0.019), while it decreased for athletes in the age group of 30–34 years (r² = 0.66, P = 0.0039). For women, running speed remained stable during the study period for athletes in all age groups.

Conclusion

These data suggest that the number of finishers of masters runners older than 40 years increased for both sexes at the Marathon des Sables, as has been previously observed for single-stage ultramarathons. In contrast to women, men aged 35 to 44 years improved running speed during the study period. Future studies are needed to investigate the reasons for the growing numbers of masters athletes in endurance sports and their improvement in performance.

Age and sex interactions in mountain ultramarathon running - the Swiss Alpine Marathon

Background

The aims of the study were to examine the (a) participation, (b) difference in running times between the sexes, and (c) age-related decline in the running times of ultramarathoner women and men competing in the Swiss Alpine Marathon from 1998 to 2011.

Methods

The ultramarathoners competing in the Swiss Alpine Marathon were analyzed in terms of participation, difference in running times between the sexes, age of the fastest runners, and age-related decline in the fastest running times. The race covers a distance of 78 km, with a total altitude change of approximately 2260 m. A total of 12,194 men and 1781 women finished the race between 1998 and 2011.

Results

Women’s participation increased from approximately 10% in 1998 to approximately 16% in 2011 (r² = 0.57; P = 0.001), but participation remained unchanged in men (r² = 0.17; P > 0.05). Over the years, the top ten women showed no change in running times (r² = 0.02; P > 0.05), whereas the top ten men’s running times increased (r² = 0.46; P < 0.01). The age for peak running times increased over time both for the top ten women (r² = 0.58; P < 0.01) and for the top ten men (r² = 0.40; P = 0.01).

Conclusion

Among the top women, participation increased, the age for peak running times increased, and the running times remained unchanged. Among the men, however, the participation remained steady, and both the peak running-time age and the running times increased.

Retirement intentions: what is the role of push factors in predicting retirement intentions?

Population ageing will significantly impact labour markets in most Organisation for Economic Cooperation and Development countries and as a result individuals will need to remain in paid employment for longer to fund their retirement years. This study examines the retirement intentions of employees of a large public-sector organisation located in Victoria, Australia that was interested in developing policies to assist with retention of their mature-age workforce. Multivariate regression analyses were used to identify the most important predictors of intention to retire. The dependent variable, Intended timing of retirement, was analysed in two forms, as continuous and dichotomised measures. Age and Length of service were strong independent predictors of Intention to retire soon (within five years). Of the work factors that were analysed (Job satisfaction, Job demands, Job control, and Social cohesion), low Job satisfaction and high Social cohesion scores indicated an increased likelihood of retiring soon. The results provide some insight into the development of organisational interventions that might assist with retaining older employees for longer.

Trends in the health care use and expenditures associated with no-lost-time claims in Ontario: 1991 to 2006

OBJECTIVE

To examine trends in health care usage and expenditures associated with no-lost-time claims in Ontario over a 15-year period.

METHODS

A secondary analysis of administrative workers' compensation claims occurring between 1991 and 2006 (N = 2,290,101). We used regression analysis to model health care expenditures using a zero-inflated linear model, adjusting for age, gender, industry group and size of payroll.

RESULTS

The probability of using health care increased over the time period. Health care expenditures per claim declined between 1991 and 1997, but then increased between 1998 and 2006, coinciding with the introduction of occupational health and safety legislation promoting early return to work in Ontario.

CONCLUSIONS

Our results provide support to the hypothesis that the increasing use of workplace accommodation since 1998 is a driver of the relatively stable rate of no-lost-time claims in Ontario.

Age differences in strain and emotional reactivity to stressors in professional careers

While age differences of workers gain increasing importance because of demographic changes in most industrialized countries, age differences in stress experience and resistance have been rarely addressed. In this initial empirical study, we explore the general relationship of age and strain as a function of three processes: (1) older workers might experience less strain because of better coping strategies; (2) older workers might experience more strain because of higher vulnerability; or (3) age and strain might be curvilinearly related with highest strain reported by middle-age workers. Using both general and experience-based measures, strain and emotional reactivity to stressful job events were reported by 274 workers aged between 18 and 65 years. Results showed an inverted U-shaped relationship between age and strain experience.

Age-related differences in profiles of mood-change trajectories

As a group, older adults report positive affective lives. The extent to which there are subgroups of older adults whose moods are less positive, however, is unclear. Our aim in the present study was to identify and characterize different subgroups of adults who exhibit distinct trajectories of mood change across a relatively short time period. Seventy-nine young and 103 older adults continuously reported their moods while viewing emotional and neutral faces. Cluster analysis revealed four subgroups of mood-change trajectories. Both the most positive and the most negative subgroups included more older than young adults (ps < .05), suggesting that not all older adults exhibit higher positive affect than young adults. Analyses of variance revealed that the most negative group exhibited slower processing speed, more state anxiety and neuroticism, and looked less at happy faces than the other groups (ps < .05). The results are discussed from an adult developmental perspective, focusing on the increased variability of mood trajectories in the older adults and whether this is a reflection of adaptive functioning or a potential harbinger of dysfunction.

Evaluation of three methodologies to estimate the VO2max in people of different ages

Aging and gender are factors that affect the variation of physical work capacity. The present paper highlights the importance of the metabolism used by ergonomics to establish the appropriate limits of loads at work. This study compares the aerobic capacity of people from 20 to 71 years old split in 5 different groups. The laboratory experiment tested 33 volunteers (19 women and 14 men). A submaximal step test was used to measure the VO(2) using a portable breath by breath metabolic system and a telemetric heart rate monitor. Three methods to estimate the VO(2max) were compared: 1) a direct measurement of VO(2), 2) estimation by heart rate, and 3) a step test method using predetermined charts. Significant difference was encountered among the estimation methods as well as among the age ranges (F(2,92)=6.43, p<0.05 y F(4,92)=7.18, p<0.05 respectively). The method of direct measurement and the method of predetermined charts were different for the estimation of the VO(2max) with a confidence level of 95%. The method of predetermined charts is better adapted for males and people younger than 30 years. The estimation through non invasive heart rate apparatus was a good appraiser of the maximal oxygen consumption considering both genders and all the age groups.

Developing a cardiology-oncology clinical practice guideline

Clinical Practice Guidelines (CPG) have become an increasingly common method to assist practitioner and patient decisions about health care for specific medical problems. CPGs generally address a single medical diagnosis or syndrome leaving practitioners and patients with little guidance when two major medical diagnoses exist such as in the case of heart disease and cancer. As cancer and heart disease are both diseases of the elderly and share many common risk factors it is likely they will coexist in many patients. Thus screening for and preventing and treating heart disease in the cancer patient assumes increasing importance as aggressive cancer therapies are applied to older patients and as a growing number of cardiovascular side effects of anti-cancer therapy are described. Careful evaluation of heart disease in the cancer patient will likely improve quality of life but may also improve mortality as the presence or development of heart disease may significantly limit life-saving cancer therapies. The rationale, potential problems, and important steps in developing a cardiology-oncology guideline are discussed.

Longitudinal changes in strength of police officers with gender comparisons

Strength is a critical factor in the health and job performance of police officers. Using a retrospective longitudinal design, the purpose of this study was to identify differences in strength scores from initial recruitment to in-service tests and to compare gender differences. Strength changes were also compared in low- to high-strength groups. Strength scores included bench press, bench press/lean weight, and bench press/weight. Body weight, percent body fat, and bench press scores were retrieved for the 1990-1995 recruit classes and were paired to most recent scores on 2006 in-service fitness record. Sample included 327 police officers: 30 females and 297 males. Mean age at initial recruitment was 24.6 years and for in-service was 37.1 years. Average time between tests was 12.5 years. Over this period bench press and bench press/lean weight significantly increased for both gender groups (p <or= 0.05). Bench press/weight remained relatively consistent. When dividing the men's strength scores into five low- to high-strength groups, there tended to be an averaging effect over time with the strongest group changing least and the weakest group changing most. In conclusion, the results of this study did not follow expected strength trends, which reported annual declines in muscular strength in men and women. Overall, officers increased in strength well into their late 30s. The practical applications of this study include documented benefits gained from maintaining ongoing fitness training and testing, as well as the potentially positive role of weight gain on strength. Also, low- to high-strength groups did not change relative positions over time even with improvements in strength scores, demonstrating the importance of minimum selection criteria for police.

Work-related musculoskeletal disorders and injuries: differences among older and younger occupational and physical therapists

INTRODUCTION

Occupational and physical therapists are at significant risk of work-related musculoskeletal disorders and injuries. As the therapy workforce ages, and shortages of therapists are predicted, it is important to evaluate differences in injuries and injury behaviors between older and younger therapists.

METHODS

Half of all occupational and physical therapists practicing in Wisconsin were randomly selected for a cross sectional study examining the relationship between aging and characteristics of self-reported work injuries and musculoskeletal symptoms.

RESULTS

Data from a sample of 1,158 therapists revealed older workers to have similar injury incidence rates, however, days away from work due to injury were higher among older workers. Overall, older and younger therapists were more similar than different, especially in regards to work behaviors. Older therapists tended to report more severe pain symptoms than younger therapists and were two and a half times more likely to report that they changed jobs due to their pain symptoms.

CONCLUSIONS

Older and younger therapists have similar work-related injury experiences. Older workers may be more vulnerable to lost work time and may experience more severe pain symptoms. Many interventions exist to prevent work-related injuries to therapists and more guidance in the best way to integrate these interventions (e.g., mechanical lift devices) into therapy practice is needed.

Physical work capacity in older adults: implications for the aging worker

BACKGROUND

In many developed countries, the workforce is rapidly aging. Occupational demands however, have not decreased despite the fact that workers see a decline in physical work capacity with age. The purpose of this review is to examine the physiological adaptations to aging, the impact of aging on performance and the benefits of physical fitness in improving functional work capacity in aging individuals.

METHODS

An extensive search of the scientific literature was performed, acquiring published articles which examined the physiological changes associated with age-related decrements in the physical work capacity of healthy aging adults. The databases accessed included AARP Ageline, AccessScience, Annual Reviews, CISTI, Cochrane Library, Clinical Evidence, Digital Dissertations (Proquest), Embase, HealthSTAR, Medline, PubMed, Scopus, and PASCAL and included relevant information sites obtained on the world wide web.

RESULTS

While a great deal of variation exists, an average decline of 20% in physical work capacity has been reported between the ages of 40 and 60 years, due to decreases in aerobic and musculoskeletal capacity. These declines can contribute to decreased work capacity, and consequential increases in work-related injuries and illness. However, differences in habitual physical activity will greatly influence the variability seen in individual physical work capacity and its components. Well-organized, management-supported, work-site health interventions encouraging physical activity during work hours could potentially decrease the incidence of age-related injury and illness.

CONCLUSIONS

Age-associated functional declines and the accompanying risk of work-related injury can be prevented or at least delayed by the practice of regular physical activity. Older workers could optimally pursue their careers until retirement if they continuously maintain their physical training.

Skeletal muscle changes after hemiparetic stroke and potential beneficial effects of exercise intervention strategies

Stroke is the leading cause of disability in the United States. New evidence reveals significant structural and metabolic changes in skeletal muscle after stroke. Muscle alterations include gross atrophy and shift to fast myosin heavy chain in the hemiparetic (contralateral) leg muscle; both are related to gait deficit severity. The underlying molecular mechanisms of this atrophy and muscle phenotype shift are not known. Inflammatory markers are also present in contralateral leg muscle after stroke. Individuals with stroke have a high prevalence of insulin resistance and diabetes. Skeletal muscle is a major site for insulin-glucose metabolism. Increasing evidence suggests that inflammatory pathway activation and oxidative injury could lead to wasting, altered function, and impaired insulin action in skeletal muscle. The health benefits of exercise in disabled populations have now been recognized. Aerobic exercise improves fitness, strength, and ambulatory performance in subjects with chronic stroke. Therapeutic exercise may modify or reverse skeletal muscle abnormalities.

Study protocol: the effects of work-site exercise on the physical fitness and work-ability of older workers

Background

Older workers have a higher rate and cost of injury than younger workers and with a rapidly ageing work force there is a need to identify strategies to address this problem. Older workers are less physically active and fit than younger workers and so have reduced work ability. The reduced work ability means they are more likely to be fatigued at work and so at greater risk of injury. Exercise could potentially assist this problem. Exercise training has been previously shown to improve fitness in older people however there has been no evaluation of workplace exercise program for older workers. We do not know if the programs are feasible and can improve the fitness and work ability of older workers. We have designed a randomised controlled trial to evaluate whether exercise improves fitness and perceived work-ability of older workers.

Methods/Design

This paper describes the protocol for a trial examining the effects of a 12-week physical training program in workers over the age of 45. Participants will be randomized to an exercise or no-intervention control group. The primary outcomes are cardiorespiratory endurance, lifting capacity, upper and lower limb strength and perceived work-ability.

Discussion

This trial will test the feasibility of implementing a worksite-based exercise program as a means of improving the physical fitness and work-ability of older workers performing physically demanding work. If we demonstrate the feasibility of the program we will conduct a larger trial that additionally measures injury outcomes.

Semiparametric Analysis of Zero-Inflated Count Data

Medical and public health research often involve the analysis of count data that exhibit a substantially large proportion of zeros, such as the number of heart attacks and the number of days of missed primary activities in a given period. A zero-inflated Poisson regression model, which hypothesizes a two-point heterogeneity in the population characterized by a binary random effect, is generally used to model such data. Subjects are broadly categorized into the low-risk group leading to structural zero counts and high-risk (or normal) group so that the counts can be modeled by a Poisson regression model. The main aim is to identify the explanatory variables that have significant effects on (i) the probability that the subject is from the low-risk group by means of a logistic regression formulation; and (ii) the magnitude of the counts, given that the subject is from the high-risk group by means of a Poisson regression where the effects of the covariates are assumed to be linearly related to the natural logarithm of the mean of the counts. In this article we consider a semiparametric zero-inflated Poisson regression model that postulates a possibly nonlinear relationship between the natural logarithm of the mean of the counts and a particular covariate. A sieve maximum likelihood estimation method is proposed. Asymptotic properties of the proposed sieve maximum likelihood estimators are discussed. Under some mild conditions, the estimators are shown to be asymptotically efficient and normally distributed. Simulation studies were carried out to investigate the performance of the proposed method. For illustration purpose, the method is applied to a data set from a public health survey conducted in Indonesia where the variable of interest is the number of days of missed primary activities due to illness in a 4-week period.

Construction work and risk of occupational disability: a ten year follow up of 14,474 male workers

AIMS

Most industrialised countries have public income maintenance programmes to protect workers in case of disability but studies addressing disability risk of specific professional groups are rare. The objective of this study was to establish a detailed pattern of the nature and extent of occupational disability among construction workers.

METHODS

A cohort study was set up including 14,474 male workers from the construction industry in Württemberg (Germany) aged 25-64 years who underwent occupational health exams between 1986 and 1992. The cohort was linked to the regional pension register of the manual workers' pension insurance institution to identify workers who were granted a disability pension during the 10 year follow up. All-cause and cause specific standardised incidence ratios (SIR) and 95% confidence intervals (CI) were calculated using disability rates from the general workforce and from all blue collar workers in Germany as references.

RESULTS

In total, 2247 (16%) members of the cohort were granted a disability pension. Major causes of disability were musculoskeletal (45%) and cardiovascular diseases (19%). In comparison with the general workforce, construction workers experienced a higher risk of disability from cancer (SIR = 1.26; 95% CI 1.08 to 1.47), respiratory diseases (SIR = 1.27; 95% CI 1.03 to 1.55), musculoskeletal diseases (SIR = 2.16; 95% CI 2.03 to 2.30), injuries/poisoning (SIR = 2.52; 95% CI 2.06 to 3.05), and all causes combined (SIR = 1.47; 95% CI 1.41 to 1.53). When compared with the blue collar reference group, increased risks of disability among construction workers were found for musculoskeletal diseases (SIR = 1.53; 95% CI 1.44 to 1.63), injury/poisoning (SIR = 1.83; 95% CI 1.50 to 2.21), and all causes combined (SIR = 1.11; 95% CI 1.07 to 1.16).

CONCLUSIONS

Musculoskeletal diseases and external causes are major factors limiting the work capability of construction workers and lead to an increased proportion of occupational disability.

Changes in physical capacity as a function of age in heavy manual work

The objective of this study was to assess the changes in the physical capacity as a function of age in power line technicians (PLTs). The physical test was designed to closely represent the essential physical tasks of the occupation that were identified through a detailed job demand analysis. The results from the physical test showed that six out of nine test variables did not demonstrate a statistical difference between the mean scores of young (< or = 39 years) and old age (50+ years) groups. However the older group scored significantly lower in the aerobic capacity test, one-handed pull down, and both right and left standard handgrip tests. Despite these differences the older PLT appears to meet and exceed the physical requirements necessary to carry out the essential tasks of this trade. However a physical test with a high level of content and construct validity is necessary to accurately evaluate the workers physical capacity in relation to the job demands. Based on the principal of specificity for muscle training and testing, this study has demonstrated that heavy manual work appears to maintain physical capacity specific to the task as age progresses.

Changes in Physical Capacity Among Middle-Aged Municipal Employees Over 16 Years

The purpose of the present study was to identify changes in different components of physical capacity among middle-aged women and men employed in the municipal branch for 16 years. The data were obtained by laboratory measurements and postal questionnaires. The study group consisted of 45 middle-aged subjects, who were on average 51.5 years old at the beginning of the follow-up in 1981 and 67.3 years in 1997. During the 16-year follow-up period, the average physical capacity of these workers decreased by approximately 20%. The study showed that the greatest changes occurred in isometric trunk muscle strength and in the flexibility of the spine, whereas smaller changes were noted in anthropometrics. The decrease of physical capacity was greater among men (range 11.6% to 33.7%) than among women (range 3.3% to 26.7%), although women had more individual variations. On average, people without disease or who were physically active displayed better physical capacity than people with disease or who were physically passive.

Modeling growth and senescence in physical performance among the ache of eastern Paraguay

This article seeks to partially fill a paucity of available data on physical performance in hunter-gatherer societies. Quantitative data are presented on various physical performance measures conducted on the Ache of eastern Paraguay, hunter-gatherers up to the 1970s and now part-time foragers and horticulturists. The performance battery was conducted on most individuals over 10 years of age, allowing for cross-sectional examination of growth and senescence patterns across the lifespan for both sexes. These measures tend to display steep ascents and peak in the early 20s with slight declines thereafter with age for males, whereas females demonstrate peaks in performance earlier in life, with lower or no senescence rates thereafter. The result is a convergence in physical performance between men and women at later ages. We suggest that the female physiology faces reproductive constraints to performance early in life but shifts allocation to increased work output later in life during the long human postmenopausal stage. In contrast, the male physiology maximizes work output in early adult life. These schedules of physical performance are contrasted with schedules of food production ability, which tend to occur later in life, and therefore imply that skill rather than strength alone is an important component of the human foraging niche.

Retaining the older nurse

The nursing workforce is aging more rapidly than the workforce as a whole, and fewer young people are entering the profession. It is imperative that older nurses be retained, not only for their experience and expertise, but also to prevent worsening an already critical nursing shortage. A descriptive survey design was used to determine the knowledge base and plans for the aging RN workforce by North Carolina hospitals and nursing homes. Nurses over age 55 made up 14.1% of the respondents' RN staff. Most administrators are aware of the aging workforce and wish to retain older nurses. Unfortunately, 94% of facilities have no policies in place to address the needs of older nurses, and 87% admitted to having no immediate plans to do so. Specific recommendations are made to assist nurse managers in retaining the older RN.

Myths and realities of ageism and nursing

Ageism is pervasive throughout society, and it is an especially important issue for nurses because the nursing workforce is aging rapidly. This article explores ageism as it applies to women and nurses, along with the myths and realities about this prevalent attitude. It also presents strategies for managing and educating the aging nursing workforce.

Physical requirements associated with the work of aging workers in the European Union

Physical requirements of work should decline with advancing age because the dimensions of physical work capacity of individuals decline with age, too. The Second European Survey on Working Conditions in 1995/1996 was used to study the prevalences (%) of poor work postures, handling heavy loads, and repetitive work in the representative sample of employed people in the 15 European Union member states. Exposure to physical requirements was still common in the European Union. Nearly 50% of older workers (age 45 years or more) were exposed to repetitive work, about 30% had poor work postures and 15% to 20% were handling heavy loads at least half of the working time. The physical requirements were as common for older and younger (less than 45 years of age) workers. The physical requirements were most common in Mediterranean countries and least common in the northern part of Europe. The differences in prevalence rates of exposures between the countries were large, from three- to fivefold. Favorable differences between older and younger workers were more notable for older men than for older women in poor work postures and repetitive work. However, older women had less handling of heavy loads than older men. The results showed that the need for better adjustments of physical requirements with age is still very relevant in the European Union and demands urgently appropriate measures in working life.

Clinical and demographic predictors of exercise capacity in end-stage renal disease

Patients on maintenance hemodialysis therapy for end-stage renal disease have reduced exercise tolerance. Multiple processes related to uremia and hemodialysis have been implicated in the pathophysiology of this impairment. However, limited data are available to identify the separate and combined effects of clinical factors on the degree of impairment for individuals within this population. For this purpose, data from 193 patients who had undergone exercise testing for two clinical trials were retrospectively analyzed. Univariate and multiple linear regression analyses were used to identify demographic and clinical correlates of peak exercise oxygen uptake (VO2). Peak VO2 averaged 18.5 +/- 6.4 mL/min/kg. On univariate analysis, peak VO2 correlated positively with male sex and hemoglobin, serum albumin, and serum creatinine concentrations and correlated negatively with dialytic age and diagnosis of diabetes or chronic heart failure. In a multiple linear regression model, sex, hemoglobin concentration, age, and diagnosis of diabetes each remained statistically significant. Together, factors included in the model accounted for 41% of the variability in peak VO2 (P = 0.0001). Among factors not correlating significantly with peak VO2 were resting blood pressure, serum carnitine level, and urea clearance assessed by Kt/V. Findings show the range of exercise impairment among clinically stable ambulatory hemodialysis patients, which may be sufficient to interfere with normal daily activities for many of these patients. Although this impairment may be broadly attributable to physiological consequences of uremia, the degree of impairment for individual patients is predicted by demographic factors, coexistent disease, and factors potentially modified by medical therapeutics.