Lifestyle characteristics, including regular physical
exercise, smoking history and educational attainment as
well as occupational activity level were assessed with a
self-administered questionnaire and a computer-guided
personal interview. Sports activity was defined as the mean
time spent on leisure time physical activities during the
summer and winter seasons (hours per week). Body weight,
height and waist circumference were measured by trained
staff according to standard procedures with participants wearing light underwear [36]. Body mass index was calculated
by dividing weight (kg) by height (m) squared. The
prevalence of diabetes mellitus at baseline was evaluated
by a physician using information on self-reported medical
diagnosis, medication records and dietary therapy.