Demographic information
| All soldiers | Reported injury | No reported injury | |
| Participants (n) | 308 | 116 | 192 |
| Age (years) | 26.8±6.5 | 28.5±7.4 | 25.8±5.7* |
| Sex, male (%) | 254 (82.5) | 88 (75.9) | 166 (86.5) |
| Sex, female (%) | 54 (17.5) | 28 (24.1) | 26 (13.5) |
| Weight (kg) | 81.1±14.5 | 82.8±15.5 | 80.1±13.9 |
| Height (inches) | 68.1±14.0 | 67.5±16.1 | 68.5±12.7 |
| Racial background (%) | |||
| African American/Black | 72 (23.4) | 30 (25.9) | 42 (21.9) |
| Asian | 12 (3.9) | 5 (4.3) | 7 (3.6) |
| Caucasian/White | 180 (58.4) | 64 (55.2) | 116 (60.4) |
| Native American/Alaskan Native | 3 (1.0) | 3 (2.6) | 0 (0.0) |
| Pacific Islander | 9 (2.9) | 2 (1.7) | 7 (3.6) |
| Other/missing | 32 (10.4) | 12 (10.3) | 20 (10.4) |
| Rank (%) | |||
| Enlisted (E2–E9) | 259 (84.1) | 97 (83.6) | 162 (84.4) |
| Officer (O1–O5) | 38 (12.3) | 11 (9.5) | 27 (14.1) |
| Warrant officer | 11 (3.6) | 8 (6.9) | 3 (1.6) |
| Time in service (years) | 5.2±5.4 | 6.3±6.3 | 4.6±4.7* |
Age, weight, height and time in service are mean±SD. Sex, racial background and rank are frequencies (%).
*P<0.050.