Physical activity and risk of workplace and commuting injuries: a cohort study.

OBJECTIVE: Leisure-time physical activity (PA) has been hypothesized to reduce the likelihood of occupational injuries, but it is unclear whether this association varies between workplace and commuting injuries. The aim of this study was to examine the association between PA and risk of workplace and commuting injuries. METHODS: Data were derived from the Finnish Public Sector study including 82 716 person-observations (48 116 participants). PA was requested repeatedly in four questionnaire surveys between 2000-2012. The average level of PA from two subsequent questionnaires was used to assess long-term PA. To obtain a 1-year incidence of injuries, participants were linked to occupational injury records from the national register. Logistic regression analysis with generalized estimating equations was used to examine the association between PA and injury risk. The analysis was adjusted for age, sex, education, work schedule, job demand, sleep difficulties, cardiovascular diseases, diabetes, and depression for workplace and commuting injuries, and workplace injuries were additionally adjusted for physical heaviness of an occupation and injury risk by occupation. RESULTS: Higher level of PA was associated with a lower risk of workplace injuries compared to inactive participants [odds ratio (OR) 0.85, 95% confidence interval (CI) 0.73-0.98]. This association was most marked in the ≥50-year-old age group (OR 0.78, 95% CI 0.64-0.99). No association between the PA and the risk for commuting injuries was observed. CONCLUSION: Higher PA is associated with lower risk of workplace injuries particularly among older employees.

Sleep duration and sleep difficulties as predictors of occupational injuries: a cohort study.

STUDY OBJECTIVES: To examine the association between sleep duration and sleep difficulties with different types and causes of workplace and commuting injuries. METHODS: The data were derived from the Finnish Public Sector study including 89.543 participants (178.309 person-observations). Participants reported their sleep duration and sleep difficulties between 2000 and 2012. These were linked to occupational injury records from the national register maintained by the Federation of Accident Insurance Institutions. Risk of injuries was followed up 1 year after each study wave. Logistic regression analysis with generalised estimating equations (GEEs) was used to examine the association between sleep duration/difficulties and risk of injuries, and multinomial logistic regression with GEE was used to examine the association with injury types and causes. RESULTS: Both sleep duration and difficulties were associated with injuries. Employees with short sleep (≤6.5 hours) had 1.07-fold odds of workplace injuries (95% CI 1.00 to 1.14) and 1.14 times higher odds of commuting injuries (95% CI 1.04 to 1.26) compared with employees with normal sleep duration. For employees with disturbed sleep, the corresponding ORs were 1.09-fold (95% CI 1.02 to 1.17) and 1.14-fold (95% CI 1.04 to 1.26) compared with those without sleep difficulties, respectively. The risk of commuting injuries was higher among those who had difficulty in falling asleep (OR 1.29, 95% CI 1.07 to 1.55), woke up too early (OR 1.11, 95% CI 1.00 to 1.23) or had non-restorative sleep (OR 1.18, 95% CI 1.05 to 1.33). CONCLUSIONS: Short sleep duration and sleep difficulties are associated with slightly increased risk of workplace and commuting injuries.

Concurrent changes in sleep and physical activity during the transition to retirement: a prospective cohort study.

BACKGROUND: Currently, little is known regarding whether changes in physical activity are associated with changes in sleep in general population. The aim of this study was to examine the association between changes in physical activity and changes in sleep duration and difficulties at retirement transition point. METHODS: Data from the prospective Finnish Retirement and Aging study of 2745 retired public sector employees was used. Participants answered questionnaires before and after the retirement with one year interval, in which they reported average weekly hours of physical activity, sleep duration and the frequency of sleep difficulties. The level of physical activity, classified as 'low', 'moderate' or 'high', before and after retirement was used to classify the participants to five physical activity groups. Changes in sleep duration (in minutes) and sleep difficulties (no, moderate, severe) were examined in these physical activity groups. RESULTS: Before retirement, high physical activity was associated with longest sleep duration (7 h 8 min) and low physical activity was associated with severe sleep difficulties (OR 1.23, 95% CI 1.06-1.44) in comparison to high physical activity. During retirement transition, sleep duration increased in all physical activity change groups and sleep difficulties decreased significantly in 'stable', 'increase from moderate', 'decrease from moderate' and 'decrease from high' groups. Changes in sleep duration and sleep difficulties were not statistically significantly different between the physical activity change groups. CONCLUSION: Sleep duration increases and sleep difficulties decrease after retirement. Changes in sleep during retirement transition seem to be independent of changes in physical activity during the same time period.