*2.3. Physical Activity*

Physical activity was calculated based on a 0–7 scale through a validated self-report scale (Self-Report of Physical Activity (SRPA)) embedded into our study questionnaire [44]. At baseline, the firefighters were asked to describe their physical activity levels over the past month using the following options: 0 = avoid walking or exertion (e.g., always use elevator, drive whenever possible instead of walking, biking, or rollerblading); 1 = walk for pleasure, routinely use stairs, occasionally exercise sufficiently to cause heavy breathing or perspiration; 2 = 10 to 60 min per week; 3 = over one hour per week; 4 = run less than 1 mile per week or spend less than 30 min per week in comparable physical activity; 5 = run 1 to 5 miles per week or spend 30 to 60 min per week in comparable physical activity; 6 = run 5 to 10 miles per week or spend 1 to 3 h per week in comparable physical activity; and 7 = run over 10 miles per week or spend over 3 h per week in comparable physical activity.
