Table 2

Characteristics of the included studies

StudyStudy designSample and/or sportNumber and/or rate of HSIAll factors examinedSpecific isokinetic strength measuresAll angular velocities testedTracking length
Bennell et al 16 Mixed cohortSenior male Australian rules football players
(n=102)
6 elite and 4 A-grade amateur-level teams		n=12Absolute hamstring peak torque (concentric, eccentric); absolute quadriceps peak torque (concentric, eccentric); strength ratios; between-side strength imbalances/asymmetries; leg dominance; history of HSIConcentric HS
Eccentric HS
Concentric Qu
Eccentric Qu
Conventional HS:Qu
Eccentric HS:Qu
Functional HS:Qu
Concentric HS:Opp HS
Eccentric HS:Opp HS		60°/s, 180°/s
60°/s, 180°/s
60°/s, 180°/s
60°/s, 180°/s
60°/s and 180°/s
60°/s and 180°/s
60°/s and 180°/s
60°/s and 180°/s
60°/s and 180°/s		1–2 seasons
Cameron et al 30 Mixed cohortElite Australian rules football players
(n=20)		n=6Relative hamstring peak torque (concentric); relative quadriceps peak torque (concentric); strength ratios; movement discrimination testConcentric HS
Concentric Qu
Conventional HS:Qu		60°/s
60°/s
60°/s		2 seasons
Croisier et al 19 Prospective cohortProfessional soccer players (n=462)n=35Absolute hamstring peak torque (concentric, eccentric); absolute quadriceps peak torque (concentric); between-side strength imbalances/asymmetries; strength ratiosConcentric HS
Concentric Qu
Eccentric HS
Conventional HS:Qu
Mixed HS:Qu		60°/s, 240°/s
60°/s, 240°/s
30°/s, 120°/s
60°/s and 240°/s
HSEcc 30°/s:QuCon 240°/s		1 season
Dauty et al 20 Prospective cohortProfessional soccer players
(n=194)		n=36Absolute hamstring peak torque (concentric, eccentric); absolute quadriceps peak torque (concentric); between-side strength ratios; strength ratios; strength ratio cut-offsConcentric HS
Concentric Qu
Eccentric HS
Conventional HS:Qu
Concentric HS:Opp HS
Eccentric HS:Opp HS
Mixed HS:Qu		60°/s, 240°/s
60°/s, 240°/s
30°/s
60°/s
60°/s
30°/s
HSEcc 30°/s:QuCon 240°/s		15 seasons
Fousekis et al 18 Mixed cohortProfessional soccer players (n=100)n=16Absolute hamstring peak torque (concentric, eccentric); absolute quadriceps peak torque (concentric, eccentric); strength ratios; between-side strength imbalances/asymmetries; leg length discrepancy; history of HSI; muscle flexibility; weight; height; joint stability; neuromuscular coordination; proprioception; absolute plantar and dorsi flexor peak torques (concentric, eccentric)Concentric HS
Eccentric HS
Concentric Qu
Eccentric Qu
Functional HS:Qu		60°/s, 180°/s, 300°/s
60°/s, 180°/s
60°/s, 180°/s, 300°/s
60°/s, 180°/s, 300°/s
180°/s		1 season
Henderson et al 15 Prospective cohortProfessional male soccer players
(n=36)		n=14Age; lean mass; non-countermovement jump; active and passive hip flexion range of movement; absolute and relative hamstring peak torque (concentric); absolute and relative quadriceps peak torque (concentric); Yo-Yo Intermittent Endurance Test; anaerobic capacityConcentric HS
Concentric Qu
Conventional HS:Qu		60°/s, 180°/s, 300°/s
60°/s, 180°/s, 300°/s
60°/s, 180°/s and 300°/s		1 season
Orchard17 Prospective cohortProfessional Australian rules football players
(n=37)		n=6Relative hamstring peak torques (concentric); relative quadriceps peak torques (concentric); between-side strength imbalances/asymmetries; strength ratios; anaerobic fitness; aerobic fitness; running speed; abdominal strength; flexibility; body compositionConcentric HS
Concentric Qu
Conventional HS:Qu
Concentric HS:Opp HS		60°/s, 180°/s, 300°/s
60°/s, 180°/s, 300°/s
60°/s, 180°/s and 300°/s
60°/s, 180°/s and 300°/s		1 season
Sugiura et al 33 Prospective cohortElite male sprinters
(n=30)		n=6Relative and absolute hamstring peak torque (concentric, eccentric); relative and absolute quadriceps peak torque (concentric, eccentric); relative and absolute hip extensor peak torque (concentric)Concentric HS
Eccentric HS
Concentric Qu
Eccentric Qu
Concentric hip ext
Functional HS:Qu		60°/s, 180°/s, 300°/s
60°/s, 180°/s, 300°/s
60°/s, 180°/s, 300°/s
60°/s, 180°/s, 300°/s
60°/s, 180°/s, 300°/s
60°/s		1 year
van Dyk et al 14 Prospective cohortProfessional soccer players (n=614)n=190Relative and absolute hamstring peak torque (concentric, eccentric); relative and absolute quadriceps peak torque (concentric); strength ratios; age; height; weight; BMI; history of HSI; player position; limb dominanceConcentric HS
Eccentric HS
Concentric Qu
Mixed Qu:HS		60°/s, 300°/s
60°/s
60°/s, 300°/s
QuCon 60°/s:HSCon 60°/s
QuCon 300°/s:HSCon 300°/s
QuCon 300°/s:HSEcc 60°/s		4 years
Yamada and Mastumoto31 Prospective cohortRugby players (n=21)n=7Reaction time of mental rotation (motor imagery capacity); straight leg raise angle; single leg stance tests; absolute hamstring peak torque (concentric); absolute quadriceps peak torque (concentric); strength ratiosConventional HS:Qu60°/s and 180°/s0.5 years
Yeung et al 32 Prospective cohortSprinters
(n=44)		n=8; 0.87 HSI per 1000-hour exposureTime point of season; strength ratios; hamstring flexibility; relative hamstring peak torques (concentric, eccentric); relative quadriceps peak torques (concentric); angle of peak torque; strength ratios; between-side strength imbalances/asymmetriesConcentric HS
Eccentric HS
Concentric Qu
Concentric H:Opp HS
Conventional HS:Qu
Functional HS:Qu		60°/s, 180°/s, 240°/s
60°/s, 180°/s, 240°/s
60°/s, 180°/s, 240°/s
60°/s, 180°/s and 240°/s
60°/s, 180°/s and 240°/s
60°/s, 180°/s and 240°/s		1 season
Zvijac et al 8 Case–control studyProfessional American football players
(n=1252)		n=172Playing position; absolute hamstrings peak torques (concentric); absolute quadriceps peak torques (concentric); strength ratios; between-side strength imbalances/asymmetries; initial peak torques (HS, Qu); work per repetition; fatigue index; total workConcentric HS
Concentric Qu
Conventional HS:Qu		60°/s, 300°/s
60°/s, 300°/s
60°/s and 300°/s

  • BMI, body mass index; Con, concentric; Ecc, eccentric; HS, hamstrings; HSI, hamstring strain injury; Opp, opposite; Qu, quadriceps.