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Related Experiment Video

Updated: Apr 27, 2026

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Regional differences in muscle activation during hamstrings exercise.

Brad J Schoenfeld1, Bret Contreras, Gul Tiryaki-Sonmez

  • 11Department of Health Sciences, CUNY Lehman College, Bronx, New York; 2Sport Performance Research Institute New Zealand, AUT University, Auckland, New Zealand; 3Department of Health Sciences and Human Performance, University of Tampa, Tampa, Florida; 4Department of Physical Therapy, Nova Southeastern University, Fort Lauderdale, Florida; and 5Department of Physical Medicine and Rehabilitation, University of Michigan, Ann Arbor, Michigan.

Journal of Strength and Conditioning Research
|July 1, 2014
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Summary

The lying leg curl (LLC) activates the lower hamstrings more than the stiff-legged deadlift (SLDL). This suggests exercise selection can target specific hamstring regions for muscle adaptation.

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Area of Science:

  • Exercise Physiology
  • Biomechanics
  • Muscle Physiology

Background:

  • Regional muscle activation may drive site-specific adaptations.
  • The hamstrings, being biarticular, might show differential activation based on exercise type (hip vs. knee dominant).

Purpose of the Study:

  • To compare electromyography (EMG) activity in proximal and distal hamstring regions.
  • To assess activation differences between hip-dominant (stiff-legged deadlift - SLDL) and knee-dominant (lying leg curl - LLC) exercises.

Main Methods:

  • Ten resistance-trained men participated in a within-subject design.
  • Participants performed SLDL and LLC to failure at 8 repetition maximum (8RM).
  • Surface EMG recorded normalized muscle activity in upper/lower medial/lateral hamstrings.

Main Results:

  • The LLC significantly increased normalized mean activation in lower lateral and medial hamstrings compared to SLDL.
  • EMG data indicates regional hamstring activation differences between the two exercises.

Conclusions:

  • Exercise selection, like choosing between SLDL and LLC, can target specific hamstring regions.
  • Further research is needed to confirm if these activation differences translate to superior site-specific muscle adaptations.