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 Naiquan Zheng and Jeffery E. 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… Expand
Knee biomechanics of the dynamic squat exercise.
  • R. Escamilla
  • Medicine
  • Medicine and science in sports and exercise
  • 2001
TLDR
The squat was shown to be an effective exercise to employ during cruciate ligament or patellofemoral rehabilitation, and can enhance stability if performed correctly. Expand
A Biomechanical Comparison of Back and Front Squats in Healthy Trained Individuals
TLDR
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. Expand
Alterations in Three-dimensional Knee Kinematics and Kinetics during Neutral, Squeeze and Outward Squat
TLDR
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. Expand
Effects of front and back squat techniques on patellofemoral joint kinetics in males
TLDR
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. Expand
Muscle Activation Patterns During Different Squat Techniques
TLDR
Altered muscle activation patterns during squats with intentional frontal and sagittal malalignment are demonstrated by changes in quadriceps, biceps femoris, and gastrocnemius activation during the squat cycle. Expand
The Effects of 2 Different Arm Positions on Maximum Trunk Flexion in the Bodyweight Squat
TLDR
Technique variations have been shown to alter squat mechanics and foot angle did not affect squat mechanics, but a narrow stance resulted in more gastrocnemius involvement. Expand
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TLDR
Squat was tested as motor task revealing differences in functional performance after knee arthroplasty, and FBUA performance appears to be closest to that of the CTR group. Expand
Effects of Trunk and Foot Positions on Electromyographic Activity and Co-contraction of Selected Lower Extremity Muscles During Leg-Press Resistance Training
TLDR
According to the results, it is recommended that, for the recruitment of more motor units when using the 45-degree leg-press machine, the backrest of the machine be adjusted at a 20° angle with the feet placed at the top of the foot-plate. Expand
Kinematic and kinetic effects of knee and ankle sagittal plane joint restrictions during squatting
TLDR
Hip and ankle flexion displacement significantly decreased in the contralateral (non-braced) limb during the ankle joint restricted condition, which may best serve as a general sagittal plane model for clinicians and coaches to reference when using the parallel squat in patients/athletes with knee and ankle dysfunction. Expand
Comparison of muscle activation of 3 different hip belt squat techniques
TLDR
An alternative exercise, such as the belt squat, can prioritize the load to the lower body musculature and be an effective substitute for the traditional back squat. Expand
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