Table 2.
Pre-harvest anthropometric, hydration, heat stress, and physiological measurements.
| All participants (N = 151) | MSFWs (n = 101) | Office Workers (n = 50) | p-value | |
|---|---|---|---|---|
| Anthropometric Measurements | ||||
| Weight (kg), mean (SD) | 71.0 (12.5) | 70.8 (11.4) | 71.3 (14.7) | 0.700 |
| Height (m), mean (SD) | 1.67 (0.7) | 1.63 (0.6) | 1.73 (0.7) | <0.001 |
| BMI (kg/m2), mean (SD) | 25.9 (4.1) | 26.6 (3.9) | 23.7 (4.3) | <0.001 |
| Normal: BMI < 25, n (%) | 68 (45.0) | 35 (35.0) | 33 (66.0) | |
| OW: BMI 25–29.9, n (%) | 65 (43.0) | 50 (50.0) | 15 (30.0) | <0.001 |
| Obese: BMI > 30, n (%) | 18 (12.0) | 16 (15.0) | 2 (4.0) | |
| Blood Pressure (mmHg) | ||||
| Systolic, mean (SD) | 115.1 (17.5) | 116 (16.4) | 113.0 (17.7) | 0.290 |
| Diastolic, mean (SD) | 73.2 (13.1) | 74.3 (13.4) | 71.0 (9.6) | 0.140 |
| Work intensity, heat stress and dehydration | ||||
| MWR (W/m2), mean (SD) | 146 (35.6) | 169 (43.1) | 133 (29.8) | <0.001 |
| WBGTeff (°C), mean (SD) | 17.3 (2.9) | 17.7 (3.4) | 13.7 (1.1) | <0.001 |
| PSI, GM (GSD)a | 2.4 (1.3) | 2.6 (1.9) | 1.8 (1.2) | <0.001 |
| TBW (mL/kg), mean (SD) | 39.4 (4.5) | 38.8 (3.9) | 41.0 (5.2) | 0.002 |
| S-Osmolality (mOsm/kg), mean (SD) | 264.0 (17.4) | 262.7 (19.5) | 263.7 (11.2) | 0.740 |
| Urinary Specific Gravity, n (%) | ||||
| Hydrated: SG ≤ 1.010 | 39 (25.7) | 25 (25.0) | 13 (26.0) | |
| Mildly Dehydrated: 1.010 < SG ≤ 1.021 | 37 (24.6) | 23 (23.0) | 17 (34.0) | 0.640 |
| Dehydrated: SG > 1.021 | 75 (49.7) | 53 (53.0) | 20 (40.0) | |
| Kidney Function Biomarker | ||||
| SCr (mg/dL), mean (SD) | 0.7 (0.1) | 0.7 (0.1) | 0.8 (0.2) | 0.110 |
| eGFR (mL/min/1.73m2), mean (SD) | 126 (14.2) | 125 (13.0) | 127 (16.6) | 0.390 |
Abbreviations: MSFWs, migrant seasonal farm workers; BMI, body mass index; OW, overweight; MWR, metabolic work rate; WBGTeff, effictive measure of wet and bulb global temperature (8 hour average); PSI, physiological strain index; TBW, total body water; S-OSM, serum osmolality; eGFR, estimated globular filtration rate; SD, standard deviation; SCr, serum creatinin; n, sample size; GM, geometric mean; GSD, geometric standard deviation. Statistical test performed: t-test for continuous and chi-square for categorical variables. Bolded p-values are statistically significant.
a
Variable was log-normally transformed, GM and GSD are presented.