Effects of technique variations on knee biomechanics during the squat and leg press.

@article{Escamilla2001EffectsOT,
  title={Effects of technique variations on knee biomechanics during the squat and leg press.},
  author={Rafael F. Escamilla and Glenn S. Fleisig and Nigel Zheng and Jeffrey Evan Lander and Steven W. Barrentine and James R. Andrews and Brian W. Bergemann and C. T. Moorman},
  journal={Medicine and science in sports and exercise},
  year={2001},
  volume={33 9},
  pages={
          1552-66
        }
}
PURPOSE The specific aim of this project was to quantify knee forces and muscle activity while performing squat and leg press exercises with technique variations. METHODS Ten experienced male lifters performed the squat, a high foot placement leg press (LPH), and a low foot placement leg press (LPL) employing a wide stance (WS), narrow stance (NS), and two foot angle positions (feet straight and feet turned out 30 degrees ). RESULTS No differences were found in muscle activity or knee… 

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Suitable stance width and foot placement angles should be chosen according to the targeted joint moments in order to avoid injury.

Knee biomechanics of the dynamic squat exercise.

  • R. Escamilla
  • Medicine, Biology
    Medicine and science in sports and exercise
  • 2001
The squat was shown to be an effective exercise to employ during cruciate ligament or patellofemoral rehabilitation, and can enhance stability if performed correctly.

Effects of External Load on Sagittal and Frontal Plane Lower Extremity Biomechanics During Back Squats.

The results indicate that submaximum squats performed at increased velocities can provide similar moments at the ankle and knee, but not hip, as maximal loads and significant emphasis on hip strength is necessary for heavy back squats.

A Biomechanical Comparison of Back and Front Squats in Healthy Trained Individuals

The results suggest that front squats may be advantageous compared with back squats for individuals with knee problems such as meniscus tears, and for long-term joint health.

Alterations in Three-dimensional Knee Kinematics and Kinetics during Neutral, Squeeze and Outward Squat

A neutral position is recommended to perform the squat exercise, while the squeeze squat and outward squat might contribute to the occurrence of joint pathologies.

Effects of front and back squat techniques on patellofemoral joint kinetics in males

The back squat appears to place lifters at greater risk from injury, and it may be prudent therefore for lifters who are predisposed to patellofemoral pain syndrome to utilize the front squat in their training.
...

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