Table 3.
Summary of included studies
| Author & Study Design | Prevention | Participants | Groups | Intervention | Results |
|---|---|---|---|---|---|
| Arnason et al. 28 Cohort (prospective) |
Combined 1° & 2° Prevention | Icelandic and Norwegian elite league male soccer teams (elite) | Warm-up stretching, flexibility, strength training n=8 teams (age: not reported) |
Warm-up stretching of hamstrings using contract-relax Warm-up: throughout entire season before each training session and game |
Incidence of hamstring muscle strain Eccentric training: Overall incidence of hamstring strains was 65% lower compared to control* (0.22 ± 0.06 vs. 0.62 ± 0.05; RR 0.35; 95% CI 0.19-0.62, p<0.001). Incidence of hamstring strains was lower compared to baseline (RR 0.42 [0.21-0.84], p=0.009). |
| Warm-up stretching, strength training n=11 teams (age: not reported) |
Flexibility for hamstrings based on partner contract-relax stretching Flexibility: after training 3x/week during preseason, 1-2x/week during competitive season |
Flexibility training: No significant difference was found in the incidence of hamstring strains between intervention and control (0.54 ± 0.12 vs. 0.35 ± 0.10; relative risk 1.53; 95% CI 0.76-3.08, p=0.22) | |||
| Warm-up stretching, flexibility n=7 teams (age: not reported) |
Eccentric strength training using “hamstring lowers” Eccentric: 5-week intro period, 3 sets of 12, 10, 8 reps; during preseason 3x/week, during competitive season 1-2x/week |
No difference in re-injury rates between “hamstring lowers” group compared to control and baseline. | |||
| Severity of hamstring muscle strain No difference in injury severity between “hamstring lowers” group compared to control. Injuries in the “hamstring lowers” group were less severe compared to baseline. | |||||
| Askling et al. 30 RCT |
Combined 1° & 2° Prevention | Premier league male soccer players from Sweden (elite) | Training group n=15 (age: 24±2.6 yrs) |
General training & eccentric hamstring strength training using YoYo Flywheel ergometer General training not described Eccentric: 4 sets × 8 reps; 16 sessions over 10 weeks |
Incidence of hamstring muscle strain Incidence of hamstring strains decreased in trained group (3/15) when compared to control group (10/15). |
| Control group n=15 (age: 26±3.6 yrs) |
General training General training not described | ||||
| Brooks et al. 2 Cohort (prospective) |
Combined 1° & 2° Prevention | Professional male rugby players in the English Premiership rugby union club (elite) | Strengthening (S) n=148 (age: 25.5±4.1 yrs) Strengthening & stretching (SS) n=144 (age: 25.8±4.0 yrs) |
Regular concentric & eccentric hamstring strengthening Strength: 1.2 sessions/wk; 3.6 sets × 8.2 reps (Exercises not described) Regular concentric & eccentric hamstring strengthening and static stretching Strength: 1.8 sessions/wk; 3.3 sets × 7.5 reps Flexibility: 2.6 sessions/wk; 2.8 sets held 25 seconds (Exercises not described) |
Incidence of hamstring muscle strain S: 1.1 (95% CI 0.74-1.4) injuries/1000 player hours; 26% proportion of recurrences SS: 0.59 (95% CI 0.34-0.84) injuries/1000 player hours; 28% proportion of recurrences SSN: 0.39 (95% CI 0.25-0.54) injuries/1000 player hours; 15% proportion of recurrences |
| Strengthening, stretching and Nordic† strengthening n=200 (age: 25.4±4.1 yrs) |
Regular concentric & eccentric hamstring strengthening, static stretching and eccentric strength training using “hamstring lowers” Strength: 1.3 sessions/wk; 3.0 sets × 7.5 reps Flexibility: 1.8 sessions/wk; 2.6 sets × 28 reps Eccentric: 1.3 sessions/wk; 2.8 sets × 6.7 reps (Exercises not described) |
Severity of hamstring muscle strain S: Mean 17 (95% CI 13-23) days lost per injury SS: Mean 21 (95% CI 12-30) days lost per injury SSN: Mean 14 (95% CI 9-19) days lost per injury |
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| Croisier et al. 1 Cohort (prospective) |
2° Prevention | National or international male soccer, track & field, martial arts athletes (elite) | n=18 (age: 25±8 yrs) | Initial individualized isokinetic concentric, eccentric, or combined eccentric and concentric programs 10-30 sessions; 3x/week, 4-8 reps at 30º or 120ºs−1 | Incidence of hamstring muscle strain No participants sustained a hamstring strain after return to their respective sports for 12 months. |
| Followed by 12-month standardized maintenance program, including manual muscle strengthening and static stretching | Pain of initial hamstring muscle strain Before rehabilitation, pain VAS was 5.9 ± 1.1. On return to activity pain VAS was 0.9 ± 0.6. Intervention significantly reduced pain at P < 0.001. |
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| Gabbe et al. 29 RCT |
Combined 1° & 2° Prevention | Senior or reserve grade male team from VAFA 2004 (competitive) | Eccentric strengthening n=114 (age: 23.4; range 18.0-35.0 yrs) |
Controlled hamstring lowers 5 sessions/12 weeks; 12 sets × 6 reps | Incidence of hamstring muscle strain Intervention group not at decreased risk for hamstring injury when intention to treat was analyzed (RR 1.2, 95% CI 0.5-2.8) |
| Stretching and ROM exercises n=106 (age: 23.9; range 17.4-36.0 yrs) |
Static stretching Gastrocnemius, hip flexors, hamstrings stretches held for 30 seconds; lumbar spine stretch held for 15 seconds. | Of participants who completed at least two training sessions, 4% of the eccentric strengthening group and 13.2% of stretching and ROM exercise group sustained a hamstring strain (RR 0.3, 95% CI 0.1-1.4; p=0.098) | |||
| Queiros Da Silva et al. 40 Cohort (prospective) |
2° Prevention | Male athletes with previous hamstring strain (unspecified level of competition) | n=8 (age: 25±8 yrs) | Eccentric hamstrings using a Cybex® isokinetic dynamometer and classical kinesiotherapy Isokinetic training: 10-14 sessions over 38-52 days, 2x/wk minimum 4 sets × 8 reps (5º/xec); 5 sets × 8 reps (10º/xec); 6 sets × 8 reps (15º/xec) | Incidence of hamstring muscle strain recurrence During the 8-month follow-up, there were no recurrent hamstring injuries reported. |
| Sherry and Best14 RCT (prospective) |
2° Prevention | Male and female athletes with acute hamstring strain (unspecified level of competition) | Stretch and Strength (STST) n=11 (9 male, 2 female) (age: 24.3±12.4 yrs) 1° strain (n=7) 2° strain (n=4) |
Static stretching, isolated progressive hamstring resistance exercise (including eccentric “foot catches”), and icing Mean duration=33.3 days | Incidence of hamstring muscle strain STST: 6/11 injured within 2 weeks PATS: 0/13 injured within 2 weeks STST: 7/11 injured within 1 year PATS: 1/13 injured within 1 year |
| Progressive agility and trunk stabilization (PATS) n=13 (9 male, 4 female) (age: 23.2±11.1 yrs) 1° strain (n=5) 2° strain (n=8) |
Progressive agility and trunk stabilization exercises and icing Mean duration=18.8 days |