Iranian Journal of Ergonomics

Introduction: The psychological health is important factor in productivity of workforce and this parameter is effective on maximum aerobic capacity. This study was conducted to investigation of association between of psychological health and maximum aerobic capacity and determination of effective factors on general health in male workers of industrial sector of Shiraz city.

Materials and Methods: In this cross-sectional study, 500 male workers employed in Shiraz city industries participated voluntarily (age range= 20 to 59 years). The demographic questionnaire (including demographic/occupational and anthropometric (height, weight and BMI) and physiological (maximum aerobic capacity) characteristics) and General Health Questionnaire (GHQ-28) were used as data collecting tools. Data were analyzed using statistical tests including T-test and Pearson Correlation by SPSS software (Version 16.0).

Results: Mean (standard deviation) of total score of general health and maximum aerobic capacity of workers were 17.00 (9.99) and 35.95 (7.39) ml.kg-1.min-1, respectively. Statistical analysis revealed significant association between job tenure, BMI, marital status, educational level and shift working with general health. Also, the results showed that there was significantly association between "anxiety and insomnia" subscale and total score of general health with maximum aerobic capacity.

Introduction: Understanding the physical capacity of people in different weather conditions can facilitate the assignment of right jobs to right individuals. People’s physical work capacity can change in response to weather conditions. Since military forces are usually obliged to work under different weather conditions, this study aimed to assess these individuals’ physical work capacity in desired, warm-humid, and very warm-humid weather conditions.

Materials and Methods: This cross-sectional study enrolled 36 military men (age: 20-29 years). Astrand treadmill tests were used to measure the participants’ physical work capacity, maximum aerobic capacity, and maximum oxygen uptake were measured under three weather conditions (desired, warm-humid, and very warm-humid).

Results: The mean physical work capacity of the participants in desired, warm-humid, and very warm-humid weather conditions was 3.69 ± 0.52, 3.69 ± 0.55, and 3.41 ± 0.50 Kcal/min, respectively. The participants’ maximum physical capacity under the mentioned conditions was 10.87 ± 1.54, 10.84 ± 1.63, and 10.02 ± 10.48 Kcal/min, respectively. Maximum aerobic capacity of the subjects was 29.52 ± 2.52, 29.76 ± 2.65, and 28.14 ± 2.76 ml/kg/min, respectively.

Conclusion: According to our findings, people have similar physical work capacity under desired and warm-humid weather conditions. However, physical work capacity reduced in very warm-humid weather. Moreover, the participants were allowed to perform light-moderate work during a work shift.

Introduction: Firefighting is amongst jobs that require high physical strength and high aerobic capacity. These are required because of the nature and the physical demands of the job. The maximum aerobic capacities of firefighters were investigated using the step test.

Methods: This cross-sectional descriptive-analytical study was conducted on 73 firefighters. At first, demographic information was collected by a questionnaire. Then, the step was built with adjustable height, for step testing, and using the Francis method, maximum aerobic capacity of the participants, was studied. The results of the questionnaire and step test were analyzed by the SPSS 16 software.

Results: maximum aerobic capacity of firefighters was calculated as 3.65 L/min and 47.4 mL/kgmin. Moreover, the results of statistical analysis revealed a significant relationship between body mass index and exercise, and maximum aerobic capacity (P ˂ 0.05). Also no significant relationship was found between maximum aerobic capacity, age, smoking and work-related fatigue (P > 0.05).

Conclusions: Studying the firefighters cardiorespiratory capacity, to reduce the probability of firefighters injuries is very important due to occupational sensitivity and having to perform difficult tasks under demanding circumstances. The results of this study showed that maximal oxygen uptake (vo2 max) and cardiopulmonary capacity of examined firefighters are greater than the minimum amount recommended by the international association of firefighters, which can be due to regular physical fitness programs conducted by the organization.