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Compensatory Muscle Activation During Unstable Overhead Squat Using a Water-filled Training Tube
Stephen C Glass1, Robert W Albert
1Department of Movement Science, Human Performance Lab, Grand Valley State University, Allendale Michigan.
Journal of Strength and Conditioning Research
|May 31, 2017
Summary
Using a water-filled tube during overhead squats increases compensatory muscle activation in the deltoid and paraspinal muscles, especially during the eccentric phase. This instability challenges core and support muscles.
Area of Science:
- Sports Science
- Biomechanics
- Exercise Physiology
Background:
- The overhead squat is a complex exercise requiring significant core and support muscle engagement.
- Instability during exercises can enhance muscle activation and improve motor control.
- Water-filled training tools offer a unique method to introduce variable instability.
Purpose of the Study:
- To investigate compensatory muscle activation patterns in experienced weightlifters during unstable overhead squats.
- To compare muscle activation under varying water movement conditions within a water-filled training tube.
- To analyze the electromyographic (EMG) activity of specific core and support muscles.
Main Methods:
- Eleven experienced male weightlifters performed overhead squats with a water-filled tube under three conditions: 50% valve open, 100% valve open, and stable (closed valve).
- Electromyographic (EMG) data were collected from the vastus lateralis, deltoid, rectus abdominis, and paraspinal muscles during concentric and eccentric phases.
- Compensatory muscle activation was quantified using the natural log of the coefficient of variation of %MVC across repetitions.
Main Results:
- Significant compensatory muscle activation was observed in the deltoid muscle during the eccentric phase when the valve was 100% open compared to the stable condition.
- Paraspinal muscle activity demonstrated greater variability during the eccentric phase with the valve 50% open versus the stable condition.
- These findings indicate that the water-filled tube significantly alters muscle activation patterns.
Conclusions:
- The water-filled training tube effectively induces compensatory muscle activation in the deltoid and paraspinal muscles during the eccentric phase of the overhead squat.
- This type of unstable training may enhance the recruitment of stabilizing muscles, potentially improving overall strength and control.
- Further research could explore the long-term effects and optimal use of such tools in training programs.
