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Updated: Jun 28, 2026
06:36
Lower Limb Biomechanical Analysis of Healthy Participants
Published on: April 15, 2020
Muscle activation during lower body resistance training
W P Ebben1, C R Feldmann, A Dayne
1Exercise Science, Marquette University, Milwaukee, Wisconsin 53201, United States. webben70@hotmail.com
International Journal of Sports Medicine
|November 1, 2008
Summary
This study found that different resistance exercises significantly affect hamstring and quadriceps muscle activation. Exercise selection is crucial for targeting specific muscles like the biceps femoris, rectus femoris, and vastus lateralis.
Area of Science:
- Biomechanics
- Exercise Physiology
- Sports Science
Background:
- Understanding muscle activation patterns is crucial for effective exercise prescription.
- Previous research has not comprehensively compared hamstring and quadriceps activation across various knee extension resistance exercises.
Purpose of the Study:
- To evaluate the biceps femoris (BF), rectus femoris (RF), and vastus lateralis (VL) muscle activation during knee extension exercises.
- To determine the effects of exercise type on muscle activation ratios (BF/RF and BF/VL).
- To investigate if subject strength or gender influences these activation variables.
Main Methods:
- Electromyography (EMG) was used to measure muscle activation as a percentage of maximum voluntary isometric contraction (MVIC).
- Exercises evaluated included leg extension, squat, deadlift, lunge, and step up.
- Subjects comprised 20 athletes and recreationally active college students.
Main Results:
- Significant main effects for exercise type were observed for RMS EMG of BF, RF, and VL (p < 0.001).
- Significant main effects were found for BF to RF (p < 0.001) and BF to VL (p = 0.003) activation ratios between exercises.
- No significant interaction between gender and exercise type was found for any measured muscle activation.
Conclusions:
- Exercise selection significantly influences hamstring and quadriceps muscle activation and their relative activation ratios.
- Clinicians and trainers should consider these differences when prescribing exercises for hamstring and quadriceps development.
- Gender and strength levels did not significantly alter muscle activation patterns across the evaluated exercises.
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