Mean (SD) tibial and sacral impact characteristics of junior fast bowlers with (n=8) and without (n=13) a history of low back pain (junior retrospective)
| Tibial acceleration | LBP (n=8) | No-LBP (n=13) | P value | Effect size (d) | ||||
| BFI | FFI | BFI | FFI | BFI | FFI | BFI | FFI | |
| Peak Acc x (g) | 10.1 (4.6) | 28.0 (13.2) | 12.0 (4.6) | 25.0 (5.4) | 0.283 | 0.557 | −0.41 | 0.33 |
| Peak Acc y (g) | 2.5 (1.7) | 15.5 (9.2) | 2.8 (1.9) | 12.0 (6.8) | 0.676 | 0.327 | −0.18 | 0.44 |
| Peak Acc z (g) | 13.0 (5.3) | 19.1 (8.9) | 17.6 (10.7) | 16.3 (6.3) | 0.209 | 0.449 | −0.50 | 0.38 |
| Peak resultant Acc (g) | 15.4 (5.2) | 36.2 (17.5) | 19.8 (8.0) | 31.3 (7.2) | 0.141 | 0.470 | −0.63 | 0.41 |
| Time-to-peak Acc x (ms) | 28.1 (18.1) | 16.8 (4.3) | 19.6 (6.9) | 16.4 (2.7) | 0.238 | 0.982 | 0.69 | 0.09 |
| Time-to-peak resultant (ms) | 39.8 (11.6) | 59.0 (18.8) | 50.6 (28.8) | 56.5 (8.5) | 0.305 | 0.735 | −0.45 | 0.19 |
| Mean loading rate x (g.s-1) | 581.1 (396.4) | 1848.0 (959.1) | 715.2 (288.1) | 1621.1 (378.5) | 0.423 | 0.540 | −0.40 | 0.35 |
| Mean resultant loading rate (g.s-1) | 465.8 (276.8) | 897.5 (937.0) | 480.8 (232.1) | 644.6 (194.4) | 0.831 | 0.668 | −0.06 | 0.43 |
| Normalised peak Acc x (g.kg-1) | 0.2 (0.1) | 0.4 (0.2) | 0.2 (0.1) | 0.3 (0.1) | 0.416 | 0.474 | −0.35 | 0.40 |
| Normalised resultant Acc (g.kg-1) | 0.2 (0.1) | 0.5 (0.2) | 0.3 (0.1) | 0.4 (0.1) | 0.220 | 0.479 | −0.54 | 0.40 |
| Sacral acceleration | ||||||||
| Peak vertical Acc (g) | 2.5 (0.7) | 3.1 (0.6) | 2.7 (0.8) | 3.2 (0.7) | 0.366 | 0.697 | −0.40 | −0.17 |
| Peak mediolateral Acc (g) | 0.5 (0.1) | 0.6 (0.2) | 0.7 (0.3) | 1.1 (0.7) | 0.165 | 0.028 | −0.65 | −0.89 |
| Peak anterioposterior Acc (g) | 1.5 (0.7) | 1.6 (1.0) | 1.3 (0.7) | 1.4 (0.9) | 0.492 | 0.582 | 0.32 | 0.23 |
| Resultant Acc (g) | 3.0 (0.8) | 3.7 (0.8) | 3.2 (0.8) | 4.0 (0.8) | 0.691 | 0.456 | −0.18 | −0.33 |
| Time-to-peak vertical Acc (ms) | 70.1 (19.0) | 60.6 (16.5) | 72.9 (18.5) | 64.1 (10.8) | 0.749 | 0.185 | −0.15 | −0.26 |
| Time-to-peak resultant Acc (ms) | 73.6 (22.2) | 65.1 (12.8) | 75.0 (20.9) | 68.2 (13.6) | 0.891 | 0.316 | −0.06 | −0.16 |
| Mean vertical loading rate (g.s-1) | 38.7 (8.3) | 61.2 (21.5) | 46.0 (16.9) | 63.7 (17.2) | 0.204 | 0.837 | −0.51 | −0.10 |
| Normalised peak vertical Acc (g.kg-1) | 0.04 (0.01) | 0.05 (0.01) | 0.04 (0.01) | 0.05 (0.02) | 0.537 | 0.619 | −0.28 | −0.22 |
Acc, acceleration; BFI, back foot impact; FFI, front foot impact; g, units of gravity; kg, kilogram; LBP, low back pain; s, second.