Behavioural and biological relationships between leisure-time physical activity and health outcomes during shift- and night-work
Shift-work is increasingly common in society and is associated with a number of health inequalities. The health effects of shift-work can include a redudion in quality and quantity of sleep, insomnia, chronic fatigue, anxiety and depreSSion,decreased vigilance, metabolic syndrome, adverse cardiovascular (especially blood pressure), gastrOintestinal effects and reproductive effects in women. Shift-work is also associated with disturbances to a workers domestic and social life. Physical activity
... s known to either prevent or alleviate these health inequalities in those with 'normal diurnal' lifestyles such as day-workers. However, shift-work generally decreases opportunities for physical adivity. Moreover, the favourable affects of physical activity on such health inequalities have not been confirmed in shift-workers. The studies in the present thesis are designed to examine the associations between shift-work and physical activity covering a wide range of physiological and psycho-social variables in shift-workers. The first descriptive study was designed to provide the first detailed and multi-researchstrategy examination of LTPA and its correlates in shift-workers. One hundred and sixty one shift-workers partiCipated in the initial cross-sectional study. A cohort of ten of these partiCipants also volunteered for further diary-and inteNiew-based studies. PartiCipants completed the SSI together with a LTPA questionnaire. Gender, job type, age and shift-work experience were explored as correlates of LTPA. The cohort also completed a 7-day diary and wore an accelerometer for assessment of activity counts during work, leisure, and bedtime when working each shift-type (days, nights and rest). Participants also completed a semi-strudured email-administered interview. The total energy expenditure per week in LTPA of male shift-workers was found to be twice that of women. Midwives recorded the lowest LTPA. Firefighters reported the most LTPA. The time spent out of bed during night shift days was 4-h higher compared with rest days. Data from this study indicated that LTPA is generally low amongst shift-workers, the majority of whom are overweight or obese. Jobtype and gender are much more influential on LTPA than age or experience. Shift-workers spend more of their time on rest days in bed.