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Procedures for Rat in situ Skeletal Muscle Contractile Properties
Published on: October 15, 2011
Relationship Between Muscle Activity and Force During Suspended Bridge Exercises
Andrew Skibski1, Luk Devorski1, Nolan Orfield2
1REhabilitation, Athletic assessment, & DYnamic imaging (READY) Laboratory, University of Central Florida, Orlando, FL,USA.
Suspended bridge exercises effectively target erector spinae (ES) for core stability. Force output during these exercises correlates with ES activity but inversely with rectus abdominis (RA) activity.
Area of Science:
- Biomechanics
- Exercise Physiology
Background:
- Isometric core stability exercises, including the rectus abdominis (RA) and erector spinae (ES), are vital for lumbopelvic-hip complex strength and endurance.
- Suspension training offers progressive difficulty through modified bases of support or unstable elements.
- Load cells can quantify force during suspension exercises.
Purpose of the Study:
- To investigate the relationship between rectus abdominis (RA) and erector spinae (ES) muscle activity and measured force during suspended bridge exercises.
- To analyze these relationships during both bilateral and unilateral exercise variations.
Main Methods:
- Forty healthy, active participants performed bilateral and unilateral suspended bridge exercises to failure.
- Surface electromyography (sEMG) measured RA and ES muscle activity as a percentage of maximum voluntary isometric contraction.
- A load cell attached to suspension straps recorded force output throughout exercise duration.
Main Results:
- A negative correlation was observed between force and rectus abdominis (RA) activity in both bilateral (r = -.735 to -.842) and unilateral (r = -.300 to -.707) suspended bridges.
- A positive correlation was found between force and erector spinae (ES) activity in bilateral (r = .689 to .791) and unilateral (r = .418 to .448) suspended bridges.
Conclusions:
- Suspended bridge exercises are effective for targeting erector spinae (ES) to enhance core stability and endurance.
- Load cells provide a quantifiable measure of the interaction between exercisers and suspension equipment.
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