Functional limitation, postural stability, and muscle recruitment of different categories of obesity were evaluated while performing an assembly workstation task. Three workstations, those designed for the 5th, 50th, and 95th percentile workers based on anthropometric data tables, were included in the study. Functional limitation was measured using electro-goniometers and the maximum frontal functional reach (MFFR) evaluation to measure the difference in joint angles, forces plates were used to study the differences in postural stability, and EMG was used to evaluate the muscle recruitment of the soleus, frontal deltoid, and trapezius muscles. Also, a regression analysis was performed to evaluate if production efficiency rate could be predicted based on body mass index (BMI) group, gender, pace type, workstation configuration and 13 body dimensions. The results revealed that the body joint angles and muscle activation parameters were not significantly different based on the main factor BMI groups; however, significant differences were found in the two-way interactions of the BMI groups and the other factors. In regard to postural stability, the results indicated that the obese class 2 and obese class 3 groups anterior posterior sway was significantly larger than the normal weight groups. The results also revealed differences based on gender for the joint angles and muscle activation when performing the small part assemblies; however, postural sway was not affected by gender differences. Pace type (self –paced or timed-paced) significantly affected the postural stability and muscle activation when performing the work task. These differences in pace type were most prevalent when comparing the 95th percentile workstation configuration against the 5th percentile workstation configuration. In regards to productivity, gender, weight, waist-to-hip ratio and pace type seem to have a large role in the production efficiency rate. Even though an individual's BMI and the workstation layout were found to impact the body functional limitation and stability, the results showed that it doesn't affect production efficiency rate performance.

Background: Firefighters (FFs) are exposed to life-threatening conditions while carrying out their tasks. These strenuous conditions predispose them to a high rate of disability, morbidity and mortality. These hazardous conditions put them at risk for work limitations, but the literature is scarce in this matter. Objective: The overarching objective of this thesis is to determine the role of FFs health as predictors of work limitations in fire service. Specifically, the first objective is to determine whether work limitations differ among FFs based on the location or number of painful sites. The secondary objective is to determine whether non-musculoskeletal comorbid health condition predict work limitations among FFs. Participants: A convenience sample of FFs between the age of 18-60 years working in the province of Ontario, Canada. Methods: Participants completed either an online or paper-based survey including a work limitation questionnaire(WLQ-26) and a self-reported comorbidity questionnaire. For the first objective, a one-way ANOVA and post hoc test was used to determine the differences in work limitations among FFs based on the number or location of painful sites. For the secondary objective, a univariate linear regression was used to evaluate whether non-MSK comorbid health condition predict work limitations among FFs. Results: FFs with three or more painful sites had more physical limitations than FFs without pain, (Mean difference=1.03/10; 95% CI: 0.16-1.62; p=0.02). FFs with pain at the region of the spine experienced more physical limitations compared to FFs with no pain (Mean difference=0.89/10; 95% CI: 0.17-1.62; p=0.007). For the secondary objective, univariate analysis showed that having at least one comorbidity(p=0.04) had a small, but significant association with greater mental work limitations (F2,316=2.94; p=0.05; R2=0.02). Separate univariate analysis showed that women FFs having one comorbidity had a small but significant association with physical (R2=0.07; F2,97=3.92, p=0.02) and mental work limitations (R2=0.04; F2,101=1.89, p=0.15) than women without non-MSK comorbidity. Conclusion: Having multiple painful sites or pain at the spinal region influenced work limitations among FFs. Also, non-MSK comorbidity impacted mental limitations among FFs; especially among women FFs. Therefore, managing MSK and on-MSK comorbidities is a necessary health care goal to prevent work limitations. / Thesis / Master of Science (MSc)

Thesis (MComm (Industrial Psychology))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: Social anxiety symptoms are common within the community. They are often unrecognised in many organisations, with resultant significant work impairments. The aim of the study was to explore to what extent the social anxiety spectrum of symptoms influences the performance of management employees and how the disorder should be managed in the workplace. The study includes the following constructs: social anxiety spectrum, job characteristics, work limitations and perceived performance difficulties. A nonexperimental research design was used to explore the relationships between the four constructs. A convenience sample of 250 managerial employees was approached from two large organizations, one in the private, and the other in the public sector. One hundred and eighteen (118) respondents completed and returned their questionnaires. The descriptive statistics reflected a mean age of 32 years (range 20 to 56 years), with 50% males and 50% females, and a race distribution of 64% White, 29% Coloured, 4% Black and 3% Indian for the sample. The majority of the participants had been working for 0 to 5 years (37.29%). The mean years worked was 10.81 and the median 9.5 (range 0.5 to 40 years worked). A high percentage of participants (11%) were found to have social anxiety symptoms above the cut off score for a diagnosis of the disorder. The results of the present study indicated that social anxiety affects all areas of work. These symptoms were associated with several areas of work limitations and performance difficulties not restricted to social interaction or presentation. It was also found that job insecurity increases social anxiety symptoms, work limitations and perceived performance difficulties. On the other hand, it was found that organisational support may act as a buffer against demands and may decrease work limitations and perceived performance difficulties. Whilst no moderating effect was found for growth opportunities in the relationship between social anxiety and work limitations, support was found for a negative relationship with both social anxiety and work limitations. No moderating effect was found for job insecurity in the relationship between social anxiety and work limitations. However, growth opportunities as a resource were found to moderate the relationship between social anxiety symptoms and perceived performance difficulties. Evidence was also found for the moderating effect of job insecurity in the relationship between social anxiety symptoms and perceived performance difficulties. The limitations of the current study and recommendations for organisations are discussed. This study highlights the importance of social anxiety symptoms as a barrier to effective work performance. Given the fact that interventions can potentially improve social anxiety and thereby performance, this area deserves much greater research attention. / AFRIKAANSE OPSOMMING: Sosiale angssimptome kom algemeen in die gemeenskap voor. Die simptome word nie alledaags in organisaies herken nie, en mag tot merkbaar verlaagde prestasie lei. Die doel van die studie was om die mate waartoe sosiale angsspektrum-simptome die prestasie van bestuursvlak-werknemers beïnvloed te bepaal en ondersoek in te stel na wyses waarop die simptome in organisasies bestuur moet word. Die studie het die volgende konstrukte ingesluit: sosiale angsspektrum-simptome, werkseienskappe, werksbeperkinge en waargenome prestasie-uitdagings. Daar is van ’n nie-eksperimentele navorsingsontwerp gebruik gemaak om die verhoudings tussen die vier konstrukte te bestudeer. ’n Gerieflikheidsteekproef van 250 bestuursvlak-werknemers van beide ’n privaatsektor en publieke sektor organisasie is genader. Eenhonderd en agtien voltooide vraelyste is ingedien. Die beskrywende statistiek het ’n gemiddelde ouderdom van 32 jaar getoon (versprei oor 20 tot 56 jaar), met 50% manlik, 50% vroulik, en ’n rasverspreiding van 64% wit, 29% kleurling, 4% swart en 3% Indiër respondente in die steekproef. Die meerderheid van die deelnemers het vorige werkservaring van 0 tot 5 jaar (37.29%) aangedui. Die gemiddelde aantal jare van werk was 10.81 en die mediaan 9.5 (versprei oor 0.5 tot 40 jaar gewerk). ‘n Hoë voorkomssyfer (11%) van sosiale angs is in die studie gevind, bo die afsnypunt vir die diagnose van die versteuring. Die resultate van die huidige studie dui aan dat sosiale angs alle aspekte van werk beïnvloed. Hierdie simptome was geassosieer met vele areas van werksbeperkings en waargenome prestasie-uitdagings en was nie slegs tot take wat sosiale interaksie en voordragte insluit, beperk nie. Die studie het ook gevind dat werksonsekerheid sosiale angssimptome, werksbeperkings en waargenome prestasie-uitdagings verhoog. Organisasieondersteuning is aangedui as ‘n moontlike buffer teen werkseise en mag werksbeperkings en waargenome prestasie-uitdagings verminder. Geen modereringseffek is vir groeigeleenthede gevind in die verhouding tussen sosiale angs en werksbeperkings nie, maar daar is wel gevind dat groeigeleenthede ’n negatiewe verband met beide sosiale angs en werksbeperkings het. Geen modereringseffek vir werksonsekerheid in die verhouding tussen sosiale angs en werksbeperkinge is gevind nie. Die rol van groeigeleenthede as hulpbron om die verhouding tussen sosiale angssimptome en waargenome prestasie-uitdagings te modereer, is bevestig. Getuienis is ook vir die modereringseffek van werksonsekerheid in die verhouding tussen sosiale angssimptome en waargenome prestasie-uitdagings gevind. Die beperkinge van die huidige studie en voorstelle vir organisasies word bespreek. Hierdie studie bekemtoon die belangrikheid van sosiale angssimptome as ’n hindernis met betrekking tot effektiewe werksprestasie. Ingrepe kan potensiaal sosiale angs verminder en daardeur prestasie verhoog. Hierdie aspek behoort heelwat meer navorsingsaandag in die toekoms te geniet.