Table 1.
Characteristics of the study participants.
| All (N = 77)a | Men (n = 20) | Women (n = 57) | ||||
|---|---|---|---|---|---|---|
| Age (years) | 23 | (2) | 22 | (2) | 22 | (2) |
| Professional status, n (%) | ||||||
| Student | 37 | (49) | 10 | (50) | 27 | (49) |
| Unemployed | 27 | (36) | 6 | (30) | 21 | (38) |
| Other professional activities | 11 | (15) | 4 | (20) | 7 | (13) |
| Anthropometry and body composition | ||||||
| Waist circumference (cm) | 81.3 | (14.4) | 94.6 | (15.7) | 76.7 | (10.6) |
| BMI (kg/m2) | 25.2 | (4.8) | 28.4 | (5.6) | 24.1 | (3.9) |
| LMI (kg/m2) | 14.4 | (2.3) | 17.2 | (2.2) | 13.4 | (1.4) |
| FMI (kg/m2) | 9.4 | (3) | 9.6 | (3.8) | 9.3 | (2.8) |
| Body fat (%) | 37.5 | (7) | 33.6 | (8.2) | 38.9 | (6) |
| VAT mass (g) | 340.3 | (191.3) | 488.7 | (205) | 288.2 | (157.5) |
| Cardiometabolic profile | ||||||
| Glucose (mg/dL) | 88 | (7) | 91 | (10) | 87 | (6) |
| Insulin (µIU/mL) | 8.78 | (6.60) | 11.72 | (10.80) | 7.73 | (3.85) |
| Total cholesterol (mg/dL) | 167 | (36) | 161 | (44) | 169 | (33) |
| High-density lipoprotein cholesterol (mg/dL) | 53 | (12) | 44 | (7) | 56 | (11) |
| Low density lipoprotein cholesterol (mg/dL) | 97 | (29) | 96 | (33) | 98 | (27) |
| Triglycerides (mg/dL) | 89 | (62) | 110 | (79) | 81 | (53) |
| HOMA index | 1.99 | (1.79) | 2.81 | (3.03) | 1.69 | (0.92) |
| C-reactive protein (mg/L) | 2.7 | (3.6) | 2.7 | (2.7) | 2.7 | (4) |
| Systolic pressure (mm Hg) | 115.3 | (12.4) | 126.3 | (12.3) | 111.6 | (10.1) |
| Diastolic pressure (mm Hg) | 70.2 | (8.3) | 71.8 | (11.3) | 69.6 | (7.1) |
| Muscular strength (kg) | 31.1 | (7.8) | 41.1 | (7.3) | 27.5 | (3.9) |
| Cardiorespiratory fitness (mL/kg/min) | 40.7 | (7.6) | 42.4 | (9.8) | 40.1 | (6.7) |
| Metabolic syndrome prevalence (%, ATP III and IDF) | 3 | (4) | 3 | (16) | 0 | (0) |
| Overall physical activity (mG/5 s) | 32.22 | (8.98) | 29.88 | (8.99) | 33.07 | (8.90) |
| Chronotype measures | ||||||
| Midsleep time point (hh:mm) | 04:56 | (00:58) | 05:09 | (01:02) | 04:51 | (00:56) |
| Chronotype (hh:mm) | 05:18 | (01:24) | 05:22 | (01:12) | 05:17 | (01:29) |
| Social jet lag (hh:mm) | 01:21 | (00:52) | 01:13 | (01:04) | 01:24 | (00:47) |
| Distal skin temperature variables | ||||||
| Valid days (days) | 6.1 | (0.5) | 6.1 | (0.6) | 6.1 | (0.5) |
| Wear time (hours/day) | 21 | (1.8) | 21 | (2.1) | 21 | (1.7) |
| IS | 0.45 | (0.13) | 0.40 | (0.15) | 0.47 | (0.12) |
| IV | 0.18 | (0.10) | 0.25 | (0.13) | 0.16 | (0.08) |
| RA | 0.03 | (0.02) | 0.03 | (0.02) | 0.04 | (0.02) |
| TL10 (hh:mm) | 16:24 | (02:54) | 15:51 | (03:50) | 16:36 | (02:31) |
| TM5 (hh:mm) | 04:27 | (01:57) | 03:51 | (02:43) | 04:39 | (01:35) |
| L10 (°C) | 33 | (1.1) | 32.7 | (1.4) | 33.1 | (1) |
| M5 (°C) | 35.3 | (0.7) | 34.7 | (0.5) | 35.5 | (0.6) |
| 18F-FDG–PET/CT variables | ||||||
| BAT SUV threshold | 2.10 | (0.23) | 1.97 | (0.22) | 2.14 | (0.21) |
| BAT radiodensity (HU) | −58.56 | (11.81) | −54.98 | (11.37) | −59.78 | (11.80) |
| BAT volume (mL) | 69.52 | (61.47) | 87.76 | (78.3) | 63.12 | (53.73) |
| BAT SUVmean | 3.71 | (1.90) | 3.50 | (1.42) | 3.79 | (2.04) |
| BAT SUVpeak | 11.05 | (8.46) | 10.53 | (8.07) | 11.24 | (8.66) |
| Superficial muscles SUVpeak | 0.61 | (0.15) | 0.62 | (0.11) | 0.60 | (0.17) |
| Deep muscles SUVpeak | 1.12 | (0.34) | 1.14 | (0.36) | 1.11 | (0.33) |
| All muscles SUVpeak | 0.85 | (0.22) | 0.86 | (0.20) | 0.85 | (0.22) |
| Descending aorta SUVpeak | 1.60 | (0.35) | 1.76 | (0.37) | 1.55 | (0.33) |
Continuous variables are presented as means (standard deviation), and categorical variables as numbers (percentages). ATP III = National Cholesterol Education Program Adult Treatment Panel III; BAT = brown adipose tissue; BMI = body mass index; CT = computed tomography; 18F-FDG = 18F-fluorodeoxyglucose; FMI = fat mass index; HOMA = homeostatic model assessment for insulin resistance; HU = Hounsfield units; IDF = International Diabetes Federation; IS = interday stability; IV = intraday variability; LMI = lean mass index; L10 = mean of the 10 consecutive hours with the lowest values and when they occurred (TL10); M5 = mean of the 5 consecutive hours with the highest values and when they occurred (TM5); PA = physical activity; PET = positron emission tomography; RA = relative amplitude; SUV = standardized uptake value; VAT = visceral adipose tissue.
Data were missing for professional status (remaining cases, n = 75); glycemic and lipid markers, HOMA index, and C-reactive protein (n = 76); systolic and diastolic blood pressure (n = 75); cardiorespiratory fitness (n = 76); metabolic syndrome prevalence (n = 74); resting metabolic rate (n = 72); overall PA (n = 75); chronotype measures (n = 73); and BAT radiodensity (n = 75).