Objectives: Working on large scale construction sites have been shown to have severe health consequences in terms of increased risk of hospitalization and disability retirement compared to construction work in general. The aim of the present study was to investigate whether large scale construction work involving 12-h workdays and extended workweeks leads to insufficient recovery measured as increased catabolic and decreased anabolic metabolism.
Methods: The study group comprised 40 male construction workers of which 21 had 12-h workdays and extended workweeks (56 h/workweek). The comparison group consisted of 19 male construction workers, who worked regular hours (37 h/week, weekends off). Measurements of concentrations of cortisol in saliva and free testosterone and glycosylated haemoglobin (HbA(1c)) in blood were made in a repeated measures design during 2 workweeks for both groups supplemented with 1 week off for construction workers with extended workweeks.
Results: The diurnal profile of concentrations of salivary cortisol for construction workers with extended workweeks differed from the diurnal profile of salivary cortisol for those with regular work schedules (P < 0.001). The construction workers with extended workweeks tended to have 15% [95% CI -3%; 37%] higher concentrations of free testosterone in serum compared to construction workers with regular work schedules (P = 0.09). There were no differences between the two groups with respect to concentrations of HbA(1c). There was no increasing trend in concentrations of cortisol or decreasing trend in concentrations of testosterone during the extended workweek. The diurnal profile for concentrations of cortisol differed between workdays and days off for construction workers with extended workweeks (P = 0.003).
Conclusion: In conclusion, we observed no indications of insufficient recovery in terms of increased catabolic or decreased anabolic metabolism in construction workers with 12-h workdays and extended workweeks compared to construction workers with regular work schedules.