Incidences of hamstring muscle injury per 1000 registered athletes and relative risk of injury with lower and upper limits of 95% of confidence interval (±95% CI) in male and female athletes for type, cause, event groups and age categories during outdoor (WOC 2009, WOC 2011, WOC 2013, EOC 2012 and EOC 2014) and indoor (WIC 2014, EIC 2011, EIC 2013 and EIC 2015) championships
| Outdoor championships | Indoor championships | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Male | Female | RR male vs female (±95% CI) | Male | Female | RR male vs female (±95% CI) | |||||
| Per cent | Incidence±95% CI | Per cent | Incidence±95% CI | Per cent | Incidence±95% CI | Per cent | Incidence±95% CI | |||
| Hamstring muscle injury type | ||||||||||
| Muscle tears | 75.7 | 19.3±2.8 | 77.1 | 10.0±2.1 | 1.94 (1.32 to 2.84)* moderate | 73.3 | 8.5±1.0 | 71.4 | 4.7±0.8 | 1.80 (0.63 to 5.16) small |
| Muscle cramps | 24.3 | 6.2±1.6 | 22.9 | 3.0±1.2 | 2.10 (1.05 to 4.21)* moderate | 26.7 | 3.1±0.6 | 28.6 | 1.9±0.5 | 1.64 (0.30 to 8.91) small |
| Hamstring muscle injury cause | ||||||||||
| Overuse with gradual onset | 12.2 | 3.1±1.3 | 10.4 | 1.3±0.8 | 2.31 (0.83 to 6.40) moderate | 13.3 | 1.5±0.5 | 14.3 | 0.9±0.4 | 1.64 (0.15 to 18.0) small |
| Overuse with sudden onset | 44.3 | 11.3±2.5 | 58.3 | 7.5±1.9 | 1.50 (0.95 to 2.37) small | 20.0 | 2.3±0.6 | 14.3 | 0.9±0.4 | 2.45 (0.26 to 23.5) moderate |
| Non-contact trauma | 29.6 | 7.6±2.1 | 20.8 | 2.7±1.1 | 2.80 (1.39 to 5.66)* moderate | 46.7 | 5.4±0.9 | 57.1 | 3.8±0.7 | 1.43 (0.42 to 4.87) small |
| Others | 13.9 | 3.6±1.4 | 10.4 | 1.3±0.8 | 2.64 (0.97 to 7.19) moderate | 20.0 | 2.3±0.6 | 14.3 | 0.9±0.4 | 2.45 (0.26 to 23.5) moderate |
| Missing values | 0.0 | 0.0 | 0.0 | 0.0 | ||||||
| Hamstring muscle injury severity | ||||||||||
| No time loss | 28.7 | 7.3±2.0 | 29.2 | 3.8±1.3 | 1.94 (1.04 to 3.62)* moderate | 26.7 | 3.1±0.7 | 28.6 | 1.9±0.5 | 1.64 (0.30 to 8.91) small |
| Minimal (1–3 days) | 12.2 | 3.1±1.3 | 12.5 | 1.6±0.9 | 1.92 (0.74 to 5.00) moderate | 13.3 | 1.5±0.5 | 14.3 | 0.9±0.4 | 1.64 (0.15 to 18.0) small |
| Mild (4–7 days) | 7.8 | 2.0±1.1 | 12.5 | 1.6±0.9 | 1.24 (0.44 to 3.47) small | 13.3 | 1.5±0.5 | 28.6 | 1.9±0.5 | 0.82 (0.12 to 5.80) small |
| Moderate (8–28 days) | 28.7 | 7.3±2.0 | 31.3 | 4.0±1.4 | 1.81 (0.99 to 3.33) small | 40.0 | 4.6±0.9 | 28.6 | 1.9±0.5 | 2.45 (0.50 to 12.1) moderate |
| Severe (>28 days) | 7.8 | 2.0±1.1 | 10.4 | 1.3±0.8 | 1.48 (0.50 to 4.42) small | 6.7 | 0.8±0.4 | 0.0 | 0.0±0.0 | – |
| Missing values | 14.8 | 4.2 | 0.0 | 0.0 | – | |||||
| Hamstring muscle injuries per event groups | ||||||||||
| Sprints | 46.1 | 35.0±9.3 | 50.0 | 17.9±7.1 | 1.96 (1.21 to 3.15)* moderate | 46.7 | 17.8±13.1 | 57.1 | 11.7±11.4 | 1.52 (0.45 to 5.16) small |
| Hurdles† | 10.4 | 31.4±17.5 | 8.3 | 11.8±11.5 | 2.66 (0.87 to 8.18) moderate | 13.3 | 17.1±23.5 | 28.6 | 18.9±25.9 | 0.91 (0.13 to 6.32) trivial |
| Middle distances | 4.3 | 10.7±9.3 | 8.3 | 10.3±10.0 | 1.04 (0.28 to 3.86) trivial | 0.0 | 0.0±0.0 | 0.0 | 0.0±0.0 | – |
| Long distances | 2.6 | 6.5±7.3 | 8.3 | 10.9±10.6 | 0.59 (0.13 to 2.64) moderate | 0.0 | 0.0±0.0 | 0.0 | 0.0±0.0 | – |
| Marathon | 6.1 | 23.3±17.0 | 0.0 | 0.0±0.0 | – | |||||
| Race walks† | 7.8 | 23.6±15.2 | 2.1 | 5.2±10.2 | 4.51 (0.58 to 35.4) large | |||||
| Jumps | 13.9 | 24.9±12.1 | 8.3 | 6.7±6.6 | 3.71 (1.25 to 11.0)* large | 33.3 | 14.1±12.3 | 0.0 | 0.0±0.0 | – |
| Throws† | 1.7 | 3.1±4.3 | 0.0 | 0.0±0.0 | – | 0.0 | 0.0±0.0 | 0.0 | 0.0±0.0 | – |
| Combined events† | 7.0 | 51.3±34.6 | 14.6 | 51.1±36.9 | 1.00 (0.35 to 2.84) trivial | 6.7 | 18.5±36.0 | 14.3 | 18.9±36.6 | 0.98 (0.06 to 15.3) trivial |
| Hamstring muscle injuries per age categories | ||||||||||
| <20 | 4.3 | 28.9±0.8 | 8.3 | 19.5±0.7 | 1.48 (0.40 to 5.43) small | 0.0 | 0.0±0.0 | 0.0 | 0.0±0.0 | – |
| 20–22 (Under 23) | 17.4 | 21.9±1.6 | 20.8 | 13.9±1.1 | 1.58 (0.74 to 3.34) small | 20.0 | 10.0±0.6 | 28.6 | 8.5±0.5 | 1.18 (0.20 to 6.98) trivial |
| 23–25 | 34.8 | 31.3±2.2 | 27.1 | 12.7±1.3 | 2.46 (1.32 to 4.57)* moderate | 26.7 | 9.5±0.7 | 28.6 | 6.3±0.5 | 1.50 (0.28 to 8.13) small |
| 26–29 | 30.4 | 27.8±2.1 | 25.0 | 11.7±1.2 | 2.38 (1.24 to 4.55)* moderate | 26.7 | 11.3±0.7 | 42.9 | 10.0±0.6 | 1.13 (0.25 to 4.99) trivial |
| 30–34 | 9.6 | 15.6±1.2 | 10.4 | 8.7±0.8 | 1.81 (0.63 to 5.17) small | 20.0 | 22.2±0.6 | 0.0 | 0.0±0.0 | – |
| ≥35 | 3.5 | 23.5±0.7 | 4.2 | 13.3±0.5 | 1.76 (0.33 to 9.50) small | 6.7 | 66.7±0.4 | 0.0 | 0.0±0.0 | – |
| Missing values | 0.0 | 4.2 | 0.0 | 0.0 | ||||||
| Outdoor and indoor championships | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Male | Female | RR male vs female (±95% CI) | |||||||||
| Per cent | Incidence±95% CI | Per cent | Incidence±95% CI | ||||||||
| Hamstring muscle injury type | |||||||||||
| Muscle tears | 75.4 | 16.9±2. 9 | 76.4 | 8.8±2.3 | 1.92 (1.34 to 2.75)* moderate | ||||||
| Muscle cramps | 24.6 | 5.5±1.7 | 23.6 | 2.7±1.3 | 2.02 (1.06 to 3.85)* moderate | ||||||
| Hamstring muscle injury cause | |||||||||||
| Overuse with gradual onset | 12.3 | 2.8±1.4 | 10.9 | 1.3±0.9 | 2.19 (0.86 to 5.60) moderate | ||||||
| Overuse with sudden onset | 41.5 | 9.3±2.6 | 52.7 | 6.1±1.9 | 1.53 (0.98 to 2.40) small | ||||||
| Non-contact trauma | 31.5 | 7.1±2.3 | 25.5 | 2.9±1.3 | 2.41 (1.31 to 4.41)* moderate | ||||||
| Others | 14.6 | 3.3±1.5 | 10.9 | 1.3±0.9 | 2.60 (1.04 to 6.51)* moderate | ||||||
| Missing values | 0.0 | 0.0 | |||||||||
| Hamstring muscle injury severity | |||||||||||
| No time loss | 28.5 | 6.4±2.1 | 29.1 | 3.4±1.4 | 1.90 (1.06 to 3.41)* moderate | ||||||
| Minimal (1–3 days) | 12.3 | 2.8±1.4 | 12.7 | 1.5±0.9 | 1.88 (0.77 to 4.57) small | ||||||
| Mild (4–7 days) | 8.5 | 1.9±1.2 | 14.5 | 1.7±1.0 | 1.13 (0.46 to 2.81) trivial | ||||||
| Moderate (8–28 days) | 30.0 | 6.7±2.2 | 30.9 | 3.6±1.5 | 1.89 (1.70 to 3.33)* small | ||||||
| Severe (>28 days) | 7.7 | 1.7±1.1 | 9.1 | 1.0±0.8 | 1.64 (0.56 to 4.81) small | ||||||
| Missing values | 13.1 | 3.6 | |||||||||
| Hamstring muscle injuries per event groups | |||||||||||
| Sprints | 46.2 | 31.5±7.8 | 50.9 | 16.6±6.1 | 1.89 (1.21 to 2.95)* small | ||||||
| Hurdles† | 10.8 | 28.1±14.5 | 10.9 | 13.5±10.7 | 2.08 (0.81 to 5.37) moderate | ||||||
| Middle distances | 3.8 | 7.7±6.7 | 7.3 | 7.6±7.4 | 1.01 (0.27 to 3.73) trivial | ||||||
| Long distances | 2.3 | 5.3±6.0 | 7.3 | 9.0±8.8 | 0.59 (0.13 to 2.62) moderate | ||||||
| Marathon | 5.4 | 23.3±17.0 | 0.0 | 0.0±0.0 | – | ||||||
| Race walks† | 6.9 | 23.6±15.2 | 1.8 | 5.2±10.2 | 4.51 (0.58 to 35.4) large | ||||||
| Jumps | 16.2 | 21.1±8.9 | 7.3 | 4.4±4.3 | 4.76 (1.64 to 13.8)* large | ||||||
| Throws† | 1.5 | 2.7±3.7 | 0.0 | 0.0±0.0 | – | ||||||
| Combined events† | 6.9 | 42.9±27.4 | 14.5 | 42.1±28.6 | 1.02 (0.40 to 2.58) trivial | ||||||
| Hamstring muscle injuries per age categories | |||||||||||
| <20 | 3.8 | 21.1±0.8 | 7.3 | 14.8±0.7 | 1.43 (0.39 to 5.26) small | ||||||
| 20–22 (Under 23) | 17.7 | 19.0±1.7 | 21.8 | 12.6±1.2 | 1.49 (0.74 to 2.97) small | ||||||
| 23–25 | 33.8 | 25.9±2.3 | 27.3 | 11.2±1.4 | 2.31 (1.29 to 4.12)* moderate | ||||||
| 26–29 | 30.0 | 24.2±2.2 | 27.3 | 11.3±1.4 | 2.14 (1.18 to 3.86)* moderate | ||||||
| 30–34 | 10.8 | 16.7±1.3 | 9.1 | 7.2±0.8 | 2.33 (0.84 to 6.43) moderate | ||||||
| ≥35 | 3.8 | 27.0±0.8 | 3.6 | 12.1±0.5 | 2.23 (0.44 to 11.3) moderate | ||||||
| Missing values | 0.0 | 3.6 | |||||||||
*Significant relative risk between male and female athletes (p<0.05).
†Disciplines differ for male and female athletes: hurdles: 110 m hurdles vs 100 m hurdles; race walks: 20 and 50 km vs 20 km only; throws: the weights of tools are different; and combined events: 10 vs 7 events; for male and female athletes, respectively.
Regarding event groups, the muscle injury incidences differed significantly between events for male and female athletes for outdoor and total championships (p<0.001), but not for indoors.