Iranian Journal of Ergonomics

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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.

Conclusion: General health was significantly associated with maximum aerobic capacity, job tenure, BMI, marital status, educational level and shift working in studied workers. Normal 0 false false false EN-US X-NONE FA

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This before-after clinical trial investigated the effect of daylight on morning and night melatonin, subjective general health using GHQ questionnaire, sleepiness and alertness on elderly who lived in nursing houses. Nineteen nursing home residents participated voluntarily. They exposed to daylight from 9 to 10 A.M. and from 4 to 5 P.M. for 6 weeks. General health of all participants was evaluated using general health questionnaire (GHQ) as well. Also we used of KSS and VAS questionnaire foe assessment of sleepiness and alertness. Baseline morning and night melatonin levels were 25.39 (±19.75)pg/ml, and 40.3 (±21.55)pg/ml respectively. Daylight exposure significantly affected morning melatonin at 7:00 A.M. but had no significant effect on night melatonin at 8:00 P.M. Mean score of general health changed 36.31 to 29.89 (P=0.003). Karolinska sleepiness scale (KSS) and Visual Analogue Scale (VAS) showed increase sleepiness and decrease alertness from 3:00 to 7:00 A.M. Sleepiness decreased and alertness increased during 1:00 P.M and 20:00 P.M. Overall day light exposure may delay sleep phase and circadian rhythm problems in elderly people. Anxiety and insomnia could be improved with daylight exposure. Our findings suggest that elders should be exposed to scheduled daylight in morning and evening for prevention and improvement of mental disorders. Adequate light should be provided for elder’s homes and nursing house. We have proposed to further study with a larger sample size be done to assess effect of daylight on GHQ' subscales.