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Lower Extremity Joint Moments of Collegiate Soccer Players Differ between Genders during a Forward Jump

Joseph M. Hart, J. Craig Garrison, Riann Palmieri-Smith, D. Casey Kerrigan, and Christopher D. Ingersoll

Context:

Lower extremity kinetics while performing a single-leg forward jump landing may help explain gender biased risk for noncontact anterior cruciate ligament injury.

Objective:

Gender comparison of lower extremity joint angles and moments.

Design:

Static groups comparison.

Setting:

Motion analysis laboratory.

Patients or Other Participants:

8 male and 8 female varsity, collegiate soccer athletes.

Intervention:

5 single-leg landings from a 100cm forward jump.

Main Outcome Measures:

Peak and initial contact external joint moments and joint angles of the ankle, knee, and hip.

Results:

At initial heel contact, males exhibited a adduction moment whereas females exhibited a abduction moment at the hip. Females also had significantly less peak hip extension moment and significantly less peak hip internal rotation moment than males had. Females exhibited greater knee adduction and hip internal rotation angles than men did.

Conclusions:

When decelerating from a forward jump, gender differences exist in forces acting at the hip.

Cover Journal of Sport Rehabilitation

In Journal of Sport Rehabilitation Volume 17 (2008): Issue 2 (Jan 2008)

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Hand-Held Dynamometry: Reliability of Lower Extremity Muscle Testing in Healthy, Physically Active, Young Adults

Brent M. Kelln, Patrick O. McKeon, Lauren M. Gontkof, and Jay Hertel

Context:

Hand-held dynamometry (HHD) has been shown to be a reliable, objective way to obtain strength measurements in elderly and physically impaired subjects.

Objective:

To estimate the intratester, intertester, and intersession reliability of HHD testing of lower extremity movements in young, healthy subjects.

Design:

Repeated measures.

Setting:

Sports medicine laboratory.

Participants:

Nine males and eleven females (Mean age = 26 years).

Measurements:

Strength measures of 11 right lower extremity movements were taken by 3 different testers on 2 separate days using a HHD.

Results:

Intratester ICC range was .77 to .97 with SEM range of .01 to .44 kg. Mean intertester ICC range was .65 to .87 with SEM range of .11 to 1.05 kg. Mean intersession ICC range was .62 to .92 with SEM range of .01 to .83 kg.

Conclusions:

HHD has the potential to be a reliable tool for strength measurements in healthy, strong subjects; however, there are noteworthy limitations with movements where subjects can overpower the testers.

Cover Journal of Sport Rehabilitation

In Journal of Sport Rehabilitation Volume 17 (2008): Issue 2 (Jan 2008)

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The Relationship between Isokinetic Open and Closed Chain Lower Extremity Strength and Functional Performance

Rodney Negrete and Jay Brophy

Objectives:

To determine (1) correlations between isokinetic lower extremity strength and functional performance and (2) correlations among different modes of isokinetic testing.

Design and Setting:

A correlational design with 6 measures. A series of strength, power, and agility tests was performed at a hospital-based outpatient physical therapy clinic.

Participants:

A volunteer sample of 29 male and 31 female, college-age subjects participated.

Measurements:

All subjects were tested in the following isokinetic tests: reciprocal leg press, single-leg squat, and knee extension. Performance tests included single-leg hop and vertical jump and a speed/agility test.

Results:

Analysis showed isokinetic knee extension, leg press, and single-leg squat strength significantly correlated to all functional tests. There were significant correlations among the 3 different isokinetic strength measures, as well.

Conclusions:

These results suggest a significant relationship between lower extremity open and closed chain isokinetic strength and functional performance testing.

Cover Journal of Sport Rehabilitation

In Journal of Sport Rehabilitation Volume 9 (2000): Issue 1 (Jan 2000)

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Intralimb Joint Coordination Patterns of the Lower Extremity in Maximal Velocity Phase Sprint Running

Marianne J.R. Gittoes and Cassie Wilson

This study aimed to develop insight into the lower extremity joint coupling motions used in the maximal velocity phase of sprint running. Two-dimensional coordinate data were used to derive sagittal plane joint angle profiles of sprint running trials. Intralimb joint coupling motions were examined using a continuous relative phase (CRP) analysis. The knee-ankle (KA) coupling was more out of phase compared with the hip-knee (HK) coupling across the step phase (mean CRP: KA 89.9° HK 34.2°) and produced a lower within-athlete CRP variability (VCRP) in stance. Touchdown (TD) produced more out-of-phase motions and a larger VCRP than toe-off. A destabilization of the lower extremity coordination pattern was considered necessary at TD to allow for the swing-to-stance transition. The key role that the KA joint motion has in the movement patterns used by healthy athletes in the maximal velocity phase of sprint running was highlighted.

Cover Journal of Applied Biomechanics

In Journal of Applied Biomechanics Volume 26 (2010): Issue 2 (Jan 2010)

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Test–Retest Reliability of Lower Extremity Functional Tests after a Closed Kinetic Chain Isokinetic Testing Bout

Robert C. Manske, Barbara Smith, and Frank Wyatt

Context:

Athletes are often examined for return to sports using a functional-testing algorithm. No research has determined whether a closed kinetic chain (CKC) isokinetic testing bout influences the reliability of functional tests.

Objective:

To determine whether a concentric CKC isokinetic test bout alters test–retest reliability of lower extremity functional testing.

Design:

Subjects participated in velocity-spectrum CKC isokinetic bouts on 2 days 1 week apart.

Setting:

Hospital-based clinic.

Participants:

28 normal subjects (mean age 26.7 years, height 27.2 cm, weight 75.8 kg).

Analysis and Results:

Means and SDs were determined. Intraclass correlation coefficients were used to calculate test–retest reliability and between days 1 and 2 ranged from .91 to .98.

Conclusions:

Even after a CKC isokinetic test bout, test–retest reliability of functional tests is very high. Future research should determine test–retest reliability of functional tests for patients with lower extremity pathology.

Cover Journal of Sport Rehabilitation

In Journal of Sport Rehabilitation Volume 12 (2003): Issue 2 (Jan 2003)

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Lower Extremity EMG in Male and Female College Soccer Players during Single-Leg Landing

J. Craig Garrison, Joe M. Hart, Riann M. Palmieri, D. Casey Kerrigan, and Christopher D. Ingersoll

Context:

Gender differences in muscle activity during landing have been studied as a possible contributing factor to the greater incidence of anterior cruciate ligament injuries in women.

Objective:

To compare root-mean-square (RMS) electromyography (EMG) of selected lower extremity muscles at initial contact (IC) and at peak knee internal-rotation (IR) moment in men and women during landing.

Design:

Preexperimental design static-group comparison.

Setting:

Motion-analysis laboratory.

Participants:

16 varsity college soccer players (8 men, 8 women).

Main Outcome Measures:

EMG activity of the gluteus medius, lateral hamstrings, vastus lateralis, and rectus femoris during landing.

Results:

When RMS EMG of all muscles was considered simultaneously, no significant differences were detected between genders at IC or at peak knee IR moment.

Conclusion:

Male and female college soccer players display similar relative muscle activities of the lower extremity during landing. Gender landing-control parameters might vary depending on the technique used to analyze muscle activity.

Cover Journal of Sport Rehabilitation

In Journal of Sport Rehabilitation Volume 14 (2005): Issue 1 (Jan 2005)

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The Relationship between Lower Extremity Isokinetic Work and Single-Leg Functional Hop-Work Test

Robert English, Mary Brannock, Wan Ting Chik, Laura S. Eastwood, and Tim Uhl

Context:

Lower extremity functional testing assesses strength, power, and neuro-muscular control. There are only moderate correlations between distance hopped and isokinetic strength measures.

Objective:

Determine if incorporating body weight in the single-leg hop for distance increases the correlation to isokinetic measures.

Study Design:

Correlational study.

Setting:

Musculoskeletal laboratory.

Participants:

30 healthy college students; 15 men and 15 women; ages 18 to 30 years.

Main Outcome Measures:

Isokinetic average peak torque and total work of quadriceps and hamstrings and single-leg hop work and distance.

Results:

Significant correlations include hop work to total-work knee extension (r = .89), average peak-torque knee extension (r = .88), distance hopped to total-work knee extension (r = .56) and average peak-torque knee extension (r = .63). Correlations involving hop work were greater than distance hopped (P < .05).

Conclusions:

Use of body weight in the assessment of distance hopped provides better information about the patient’s lower extremity strength and ability than the distance hopped alone.

Cover Journal of Sport Rehabilitation

In Journal of Sport Rehabilitation Volume 15 (2006): Issue 2 (Jan 2006)

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Lower Extremity Kinematics and Kinetics When Landing From Unloaded and Loaded Jumps

Ina Janssen, Jeremy M. Sheppard, Andrew A. Dingley, Dale W. Chapman, and Wayne Spratford

Countermovement jumps loaded with a weighted vest are often used for the training of lower body power to improve jump performance. However, it is currently unknown how this added load affects the lower extremity kinematics and kinetics, in particular whether this results in an increased injury risk. Therefore, the purpose of this investigation was to determine how lower extremity kinematics and kinetics during landing are affected by loaded jumps as demonstrated in a volleyball block jump landing. Ten elite male volleyball players performed block jump landings in an unloaded and loaded (9.89 kg) condition. Kinematic and kinetic landing data from the three highest jumps were collected and assessed. Paired samples t test was used to establish whether load condition had a significant effect on lower extremity kinematics and kinetics. Hip flexion was significantly greater in the unloaded condition compared with the loaded condition (p = .004). There was no significant difference in any other kinematic or kinetic variables measures between the unloaded and loaded conditions. These results suggest that landing from loaded volleyball block jumps does not increase injury risk compared with unloaded jumps in elite male volleyball players.

Cover Journal of Applied Biomechanics

In Journal of Applied Biomechanics Volume 28 (2012): Issue 6 (Jan 2012)

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Effects of Turn Angle and Pivot Foot on Lower Extremity Kinetics during Walk and Turn Actions

Dali Xu, John W. Chow, and Y. Tai Wang

This study examined lower extremity joint moments during walk and turn with different turn angles and pivot feet. Seven young adults (age 21 ± 1.3 yrs) were asked to walk at a self-selected speed (1.35 ± 0.15 m/s) and to turn to the right using right (spin turn) and left (step turn) pivot feet at turn angles of 0° (walking straight), 45°, and 90°. Video and forceplate systems were employed for kinematic and kinetic data collection. Inverse dynamics approach was used to compute joint moments using segmental kinematics, ground reaction forces, and moments. The participants decreased their forward speed by increasing the ankle plantar flexion moment as the turn angle increased. The peak ankle plantar flexion moment during the braking phase increased with increasing turn angle for both spin and step turns. Ankle invertor moments were observed only in spin turns, suggesting that more ankle muscles are involved in spin turns than in step turns. The turn angle had a significant effect on the transverse plane moment profiles at the different lower extremity joints. The results suggest that the loading patterns of different anatomical structures in the lower extremity are affected by both turn angle and pivot foot during walk and turn actions.

Cover Journal of Applied Biomechanics

In Journal of Applied Biomechanics Volume 22 (2006): Issue 1 (Jan 2006)

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What Is the Influence of Cambered Running Surface on Lower Extremity Muscle Activity?

Birgit Unfried, Arnel Aguinaldo, and Daniel Cipriani

Running on a road for fitness, sport, or recreation poses unique challenges to the runner, one of which is the camber of the surface. Few studies have examined the effects of camber on running, namely, kinematic studies of the knee and ankle. There is currently no information available regarding muscle response to running on a cambered road surface. The purpose of this study was to investigate the effects of a cambered road on lower extremity muscle activity, as measured by electromyography in recreational runners. In addition, this study examined a true outdoor road surface, as opposed to a treadmill surface. The mean muscle activity of the tibialis anterior, lateral gastrocnemius, vastus medialis oblique, biceps femoris, and gluteus medius were studied. Fifteen runners completed multiple running trials on cambered and level surfaces. During the stance phase, mean activities of tibialis anterior, lateral gastrocnemius, and vastus medialis oblique were greater on the gutter side than the crown side. There were no differences in mean muscle activity during the swing phase. The findings of this study suggest that running on a road camber alters the activity of select lower extremity muscles possibly in response to lower extremity compensations to the cambered condition.

Cover Journal of Applied Biomechanics

In Journal of Applied Biomechanics Volume 29 (2013): Issue 4 (Jan 2013)