Effect of Cognitive Dual Tasks on Lower Extremity Kinematics and Ground Reaction Force during Repeated Tuck Jump Landings

Large number of studies showed that landing with great impact forces may be a risk factor for knee injuries. The purpose of this study was to illustrate the different landing loads to lower extremity of both genders and examine the relationships among selected lower extremity kinematics and kinetics during the landing of a stop-jump task. A total of 35 male and 35 female healthy subjects were recruited in this study. Each subject executed five experiment actions. Lower extremity kinematics and kinetics were synchronously acquired. The comparison of lower extremity kinematics for different genders showed significant difference. The knee and hip maximum flexion angle, peak ground reaction force and peak knee extension moment have significantly decreased during the landing of the stop-jump task among the female subjects. The hip flexion angle at the initial foot contact phase showed significant correlation with peak ground reaction force during landing of the stop-jump task (r=-0.927, p<0.001). The knee flexion angle at the initial foot contact phase had significant correlation with peak ground reaction force and vertical ground reaction forces during landing of the stop-jump task (r=-0.908, p<0.001; r=0.812, P=0.002). A large hip and knee flexion angles at the initial foot contact with the ground did not necessarily reduce the impact force during landing, but active hip and knee flexion motions did. The hip and knee flexion motion of landing was an important technical factor that affects anterior cruciate ligament (ACL) loading during the landing of the stop-jump task.

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Patellar Tendon Straps Decrease Pain and May Alter Lower Extremity Kinetics in Those With Patellar Tendinopathy During Jump Landing

International Journal of Athletic Therapy & Training ◽

10.1123/ijatt.2016-0014 ◽

2017 ◽

Vol 22 (4) ◽

pp. 51-57 ◽

Cited By ~ 2

Author(s):

Adam B. Rosen ◽

Jupil Ko ◽

Kathy J. Simpson ◽

Cathleen N. Brown

Keyword(s):

Lower Extremity ◽

Patellar Tendon ◽

Ground Reaction Force ◽

Reaction Force ◽

Patellar Tendinopathy ◽

Jump Landing ◽

Drop Jumps ◽

Kinetics Of

Patellar tendinopathy is often managed with a patellar tendon strap, however, their effectiveness is unsubstantiated. The purpose of this study was to determine if straps altered pain or lower extremity kinetics of individuals with patellar tendinopathy during landing. Thirty participants with patellar tendinopathy and 30 controls completed drop jumps with and without patellar tendon straps. Wearing the strap, tendinopathy participants demonstrated significantly decreased pain and reduced knee adductor moment; all participants displayed significantly decreased anterior ground reaction force while wearing a strap. Patellar tendon strapping may reduce pain due to alterations in direction and magnitude of loading.

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Lower Limb Joint Kinetics During Moderately Sloped Running

Journal of Athletic Training ◽

10.4085/1062-6050-45.1.16 ◽

2010 ◽

Vol 45 (1) ◽

pp. 16-21 ◽

Cited By ~ 25

Author(s):

Gaurav Telhan ◽

Jason R. Franz ◽

Jay Dicharry ◽

Robert P. Wilder ◽

Patrick O. Riley ◽

...

Keyword(s):

Lower Extremity ◽

Ground Reaction Force ◽

Injury Risk ◽

Reaction Force ◽

Surface Slope ◽

Joint Moments ◽

Joint Kinetics ◽

3 Dimensional ◽

Modifiable Factors ◽

The Impact

Abstract Context: Knowledge of the kinetic changes that occur during sloped running is important in understanding the adaptive gait-control mechanisms at work and can provide additional information about the poorly understood relationship between injury and changes in kinetic forces in the lower extremity. A study of these potential kinetic changes merits consideration, because training and return-to-activity programs are potentially modifiable factors for tissue stress and injury risk. Objective: To contribute further to the understanding of hill running by quantifying the 3-dimensional alterations in joint kinetics during moderately sloped decline, level, and incline running in a group of healthy runners. Design: Crossover study. Setting: Three-dimensional motion analysis laboratory. Patients or Other Participants: Nineteen healthy young runners/joggers (age = 25.3 ± 2.5 years). Intervention(s): Participants ran at 3.13 m/s on a treadmill under the following 3 different running-surface slope conditions: 4° decline, level, and 4° incline. Main Outcome Measure(s): Lower extremity joint moments and powers and the 3 components of the ground reaction force. Results: Moderate changes in running-surface slope had a minimal effect on ankle, knee, and hip joint kinetics when velocity was held constant. Only changes in knee power absorption (increased with decline-slope running) and hip power (increased generation on incline-slope running and increased absorption on decline-slope running in early stance) were noted. We observed an increase only in the impact peak of the vertical ground reaction force component during decline-slope running, whereas the nonvertical components displayed no differences. Conclusions: Running style modifications associated with running on moderate slopes did not manifest as changes in 3-dimensional joint moments or in the active peaks of the ground reaction force. Our data indicate that running on level and moderately inclined slopes appears to be a safe component of training regimens and return-to-run protocols after injury.

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