Table 1 Summary of the demographic data
Characteristics | Total n = 1215 | Age group by years | |||
|---|---|---|---|---|---|
≤ 10 n = 195 | 11–12 n = 290 | 13–14 n = 320 | 15–16 n = 410 | ||
Position | |||||
Pitcher, n (%) | 216 (17.8) | 13 (6.7) | 75 (25.9) | 43 (13.4) | 85 (20.7) |
Fielder, n (%) | 999 (82.2) | 182 (93.3) | 215 (74.1) | 277 (86.6) | 325 (79.3) |
Gender | |||||
Male, n (%) | 1193 (98.2) | 183 (93.8) | 283 (97.6) | 317 (99.1) | 410 (100) |
Height | |||||
Median (IQR), cm | 163 (147–170) | 136 (132–142) | 146 (141–154) | 164 (159–168) | 170 (167–174) |
Body mass | |||||
Median (IQR), kg | 54 (41–64) | 32 (29–38) | 41 (35–49) | 54 (48–60) | 65 (59–71) |
Rohrer index | |||||
Median (IQR) | 127 (117–139) | 128 (118–144) | 127 (117–140) | 122 (112–134) | 131 (122–141) |
Years of baseball experience | |||||
Median (IQR), years | 4 (3–6) | 2 (1–4) | 3 (2–5) | 4 (2–5) | 7 (5–8) |
Total amount of practice per week | |||||
Median (IQR), h | 15 (11–20) | 12 (10–16) | 12 (10–16) | 12 (10–15) | 24 (20–30) |
Previous history of musculoskeletal injuries during the season | |||||
Hip/Groin, n (%) | 13 (1.1) | 0 (0.0) | 0 (0.0) | 4 (1.3) | 9 (2.2) |
Thigh, n (%) | 14 (1.2) | 0 (0.0) | 1 (0.3) | 4 (1.3) | 9 (2.2) |
Knee, n (%) | 36 (3.0) | 0 (0.0) | 5 (1.7) | 9 (2.8) | 22 (5.4) |
Positive Thomas test | |||||
TS, n (%) | 515 (42.4) | 61 (31.3) | 120 (41.4) | 134 (41.9) | 200 (48.8) |
NTS, n (%) | 498 (41.0) | 54 (27.7) | 108 (37.2) | 133 (41.6) | 203 (49.5) |
Positive SLR test | |||||
TS, n (%) | 262 (21.6) | 25 (12.8) | 59 (20.3) | 80 (25.0) | 98 (23.9) |
NTS, n (%) | 229 (18.8) | 24 (12.3) | 57 (19.7) | 77 (24.1) | 71 (17.3) |
Positive HKT | |||||
TS, n (%) | 517 (42.6) | 19 (9.7) | 91 (31.4) | 159 (49.7) | 248 (60.5) |
NTS, n (%) | 527 (43.4) | 20 (10.3) | 93 (32.1) | 166 (51.9) | 248 (60.5) |