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Do sweep rowers symmetrically activate their low back muscles during indoor rowing?
N G Readi1,2, V Rosso1, A Rainoldi1
1Scuola Universitaria Interfacoltà di Scienze Motorie, Dipartimento di Scienze Mediche, Università degli Studi di Torino, Torino, Italy.
Sweep rowers exhibit asymmetric low back muscle activation during indoor rowing, indicating potential adaptations beyond equal loading. These findings highlight the sensitivity of electromyography (EMG) to subtle muscle activation differences.
Area of Science:
- Sports Medicine
- Biomechanics
- Exercise Physiology
Background:
- Sweep rowing involves asymmetrical loading demands on the body.
- Indoor rowing typically imposes equal loading on left and right sides.
- Asymmetric muscle activation in sweep rowers may persist even in symmetrical exercise.
Purpose of the Study:
- To investigate asymmetric low back muscle activation in elite sweep rowers during indoor rowing.
- To determine if indoor rowing reveals underlying asymmetric adaptations from sweep rowing.
- To analyze the spatial distribution of electromyograms (EMG) along the lumbar spine.
Main Methods:
- Six elite sweep rowers performed indoor rowing exercise.
- Surface electromyograms (EMGs) were recorded from lumbar spine locations.
- Trunk kinematics and EMG amplitude distribution were analyzed and compared between sides.
Main Results:
- Significant differences in EMG amplitude were observed between trunk sides.
- The region of greatest EMG amplitude varied between participants and sides.
- Trunk lateral inclination and rotation were minimal (<5°), suggesting activation differences are not due to gross movement.
Conclusions:
- Sweep rowers demonstrate asymmetric low back muscle activation during indoor rowing.
- Factors beyond the rowing side contribute to these observed asymmetries.
- Surface EMG amplitude distribution effectively detects bilateral changes in back muscle activation.
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