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Objective: To compare the differences in the concentric hamstrings:quadriceps (H:Q) ratio among athletes in different sports at 3 velocities.
Design and Setting: We measured the H:Q ratio of both knees using the Biodex Pro Isokinetic Device.
Subjects: Eighty-one male and female collegiate athletes.
Measurements: We performed analyses for sport, velocity, and side of body for each sex. To compare the means of the concentric H:Q ratios for mean peak torque and mean total work, a 2 x 3 x 4 mixed-factorial analysis of variance was
computed for women and a 2 x 2 x 3 mixed-factorial analysis of variance was computed for men.
Results: We observed no significant interactions for men and women for the concentric H:Q ratio for mean peak torque. There was a significant mean difference among velocity conditions and a significant difference for men with respect to velocity. No significant differences were found for side of body or sport.
Conclusions: The H:Q ratio increased as velocity increased. No differences existed for the H:Q ratio for sport or side of body.
Key Words: knee, sex, concentric, eccentric
Isokinetic assessment can be used to measure torque values at several joints in the body; the knee is perhaps the joint most commonly tested. This assessment typically involves comparing the involved joint with the uninvolved joint.1 Isokinetic testing can be used to evaluate quadriceps and hamstrings muscle strength, providing a determination of the magnitude of torque generated, and subsequently, the hamstrings to quadriceps (H:Q) strength ratio.2
The H:Q ratio has been used to examine the similarity between hamstrings and quadriceps moment-velocity patterns and to assess knee functional ability and muscle balance.1,3,4 This ratio has conventionally been expressed as concentric hamstrings to quadriceps strength5,6 and recently as eccentric hamstrings to concentric quadriceps strength.7 Researchers have examined this ratio in both sexes and in different age groups and rehabilitation settings.1,6,8-21 The H:Q ratio is velocity and position dependent7 and may reflect predisposition to injury.22,23 This predisposition may result from decreased antagonist hamstrings coactivation during extension loads.24
Baratta et al24 examined antagonist musculature assisting in knee joint stability. Athletes who did not regularly exercise their hamstrings had a significant decrease in hamstrings activation compared with normal healthy subjects and athletes who regularly exercised the hamstrings...