Comparison of hamstring injury incidences between teams in which all players performed the Nordic Hamstring Exercise (NHE) (n=5) and teams in which only some players performed NHE (n=6)
| Team training (n=5) | No team training (n=6) | Rate ratio | P value | |
| Training hamstring injury incidence, injuries/1000 hours (95% CI) | 0.6 (0.3 to 1.0) | 0.7 (0.5 to 1.1) | 0.80 (0.42 to 1.54) | 0.502 |
| Match hamstring injury incidence, injuries/1000 hours (95% CI) | 1.4 (0.6 to 3.1) | 4.0 (2.5 to 6.5) | 0.35 (0.14 to 0.89) | 0.028 |
| Hamstring injury recurrence incidence, injuries/1000 hours (95% CI) | 0.0 (0.0 to 0.2) | 0.3 (0.2 to 0.5) | 0.12 (0.02 to 0.95) | 0.045 |