JOURNAL ARTICLE

Hip-abductor fatigue and single-leg landing mechanics in women athletes

Mary F Patrek, Thomas W Kernozek, John D Willson, Glenn A Wright, Scott T Doberstein
Journal of Athletic Training 2011, 46 (1): 31-42
21214348

CONTEXT: Reduced hip-abductor strength and muscle activation may be associated with altered lower extremity mechanics, which are thought to increase the risk for anterior cruciate ligament injury. However, experimental evidence supporting this relationship is limited.

OBJECTIVE: To examine the changes in single-leg landing mechanics and gluteus medius recruitment that occur after a hip-abductor fatigue protocol.

DESIGN: Descriptive laboratory study.

PATIENTS OR OTHER PARTICIPANTS: Twenty physically active women (age  =  21.0 ± 1.3 years).

INTERVENTION(S): Participants were tested before (prefatigue) and after (postfatigue) a hip-abductor fatigue protocol consisting of repetitive side-lying hip abduction.

MAIN OUTCOME MEASURE(S): Outcome measures included sagittal-plane and frontal-plane hip and knee kinematics at initial contact and at 60 milliseconds after initial contact during 5 single-leg landings from a height of 40 cm. Peak hip and knee sagittal-plane and frontal-plane joint moments during this time interval were also analyzed. Measures of gluteus medius activation, including latency, peak amplitude, and integrated signal, were recorded.

RESULTS: A small (<1°) increase in hip-abduction angle at initial contact and a small (<1°) decrease in knee-abduction (valgus) angle at 60 milliseconds after contact were observed in the postfatigue landing condition. No other kinematic changes were noted for the knee or hip at initial contact or at 60 milliseconds after initial contact. Peak external knee-adduction moment decreased 27% and peak hip adduction moment decreased 24% during the postfatigue landing condition. Gluteus medius activation was delayed after the protocol, but no difference in peak or integrated signal was seen during the landing trials.

CONCLUSIONS: Changes observed during single-leg landings after hip-abductor fatigue were not generally considered unfavorable to the integrity of the anterior cruciate ligament. Further work may be justified to study the role of hip-abductor activation in protecting the knee during landing.

Full Text Links

Find Full Text Links for this Article

Discussion

You are not logged in. Sign Up or Log In to join the discussion.

Related Papers

Remove bar
Read by QxMD icon Read
21214348
×

Save your favorite articles in one place with a free QxMD account.

×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"