Bioelectrical impedance analyzer

Secondary outcomes included cardiometabolic parameters: body mass index (BMI), body fat percentage, waist circumference, plasma glucose, triglycerides, total cholesterol, high-density lipoprotein (HDL) cholesterol, and low-density lipoprotein (LDL) cholesterol. Height was measured with a standard clinic stadiometer and body weight with a calibrated scale while wearing light clothing with bare feet in private areas of the fire houses by trained public safety medial clinical staff at each study visit. Waist circumference was assessed using a tape measure fitted around each participant’s waist at the level of the iliac crest and measuring the circumference after expiration. A bioelectrical impedance analyzer (Tanita Corporation of America) was used to estimate body fat. Fasting blood samples were collected during fire department medical examinations, timed to the 6-month and 12-month endpoints (within 45 days). Plasma and serum samples were collected in the 15-mL ethylenediamine tetra-acetic acid tubes as appropriate for each assay, aliquoted, frozen at −80 °C, and then stored. Blood lipid profiles were determined using standardized automated high-throughput enzymatic analyses using cholesterol assay kit and reagents and triglyceride assay kit and reagents by ARCHITECT c System (Abbott Laboratories). LDL cholesterol was assessed using the Martin-Hopkins equation.

Anthropometric measurements (height, waist circumference, body weight, and body fat), as well as blood pressure measurements, were performed by trained medical staff, at the baseline study visit. Height was measured without shoes in the standing position with a standard clinic stadiometer. Waist circumference was assessed by using a tape measure snugly fitted around each participant’s waist at the level of the iliac crest and measuring the circumference after expiration. Body weight was measured with bare feet and in light clothes on a calibrated scale (Tanita). Body fat was estimated using a Bioelectrical Impedance Analyzer (Tanita). Blood pressures were measured using an appropriately sized cuff with each firefighter in the seated position in a resting state.
Hypertension was defined according to the most recent American Hypertension Guideline to having a systolic blood pressure higher than 130 or diastolic blood pressure higher than 80 (18 (link)), and we considered obesity to be any body mass index (BMI) greater than or equal to 30 kg/m², as defined by the World Health Organization (WHO) (19 (link)) and abdominal obesity was considered as a waist circumference greater than or equal to 102 cm for males and 88 cm for females (20 (link)).