Hbf 306c

Height, weight, body mass index (BMI, calculated as weight in kilograms divided by height in meters squared), waist (inches), hip (inches), waist/hip ratio, and percent body fat (Bioelectrical impedance analysis (BIA) with the Omron HBF306C handheld device)

Body weight was measured in light underwear/clothing on a calibrated scale (model no. 708, Seca, Hamburg, Germany) and height was taken from the Icelandic electronic hospital registry SAGA (TM software 3.1.39.9). Body mass index (BMI) was calculated from the height and weight (kg/m²). Participants were categorized into three BMI categories: low BMI < 23 kg/m², middle BMI 23–30 kg/m², or high BMI ≥ 30 kg/m² [24 ]. Body composition was measured using a hand-held bioelectrical impedance analysis device (BIA, Omron HBF-306C, Kyoto, Japan) [25 (link)]. Calf circumference was measured in a seated position. The tape was wrapped around the right calf and moved up and down to locate the maximum circumference in a plane perpendicular to the long axis of the calf [26 (link)]. Midarm circumference was also measured in a seated position and was taken on the left upper arm, at the mid-point between the tip of the shoulder and the tip of the elbow (olecranon process and the acromion) [27 (link)].

To assess the health status and energy balance of the participants, physical measurements were carried out on items of particular interest [4 ]. The participants’ height and waist–hip circumference were measured with a measuring tape, and their weight was measured with a scale (HD-660, Tanita Co., Tokyo, Japan). The BMI was calculated using the formula of weight (kg) divided by height squared (m²), and was categorised as follows: underweight for BMI < 18.5, normal weight for BMI 18.5–24.9, overweight for BMI 25.0–29.9, and obese for BMI > 30.0 [21 ]. Body fat percentage was measured using a handheld body fat monitor (HBF-306C, Omron Co., Tokyo, Japan). Blood pressure was measured using an upper-arm blood pressure monitor (HEM-7130-HP, Omron Co., Tokyo, Japan). Hypertensive individuals were those with systolic blood pressure (SBP) of 140 mmHg or higher and/or diastolic blood pressure (DBP) of 90 mmHg or higher, while those with severe hypertension were those with SBP of 160 mmHg or higher and/or DBP of 100 mmHg or higher [4 ]. As a proxy indicator of physical activity, step counts were measured using a wearable monitor over three consecutive dates, and average daily step counts were calculated (Fitbit Surge, Fitbit, CA, USA).