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Muscle Activation and Strength in Squat and Bulgarian Squat on Stable and Unstable Surface
Abstract
The aim of the study was to compare muscle activity using the same relative resistance in squats and Bulgarian squats on stable and unstable surface. Muscle strength and activity were assessed by 6-repetition maximum and concomitant surface electromyography. A cohort of 15 resistance-trained males performed the exercises on the floor or a foam cushion in randomized order. The muscle activity was greater in biceps femoris (63-77%, p<0.01) and core muscle external obliques (58-62%, p<0.05) for the Bulgarian squat compared to regular squats, but lower for rectus femoris (16-21%, p<0.05). Only Bulgarian squat showed differences concerning the surface, e. g. the unstable surface reduced the activation of erector spinae (10%, p<0.05) and biceps femoris (10%, p<0.05) compared to a stable surface. There were similar activations in the vasti muscles and rectus abdominis between the different exercises (p=0.313-0.995). Unstable surfaces resulted in a load decrement of 7% and 10% compared to stable surfaces (p<0.001). In conclusion, the squat was somewhat favorable for the activation of agonists, whereas Bulgarian squat was advantageous for the antagonist and somewhat for core muscles. Bulgarian- and regular squats complement each other, and it may be useful to include both in a periodized resistance training program.
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Compressive forces steadily increase when squatting from a partial to a deep position.
“As for the tibiofemoral joint, compressive forces steadily increase when squatting from a partial to a deep position.3,67”
From A Biomechanical Review of the Squat Exercise: Implications for Clinical Practice. (2024) · cites this paper as [67]
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“Furthermore, to optimize the activation of specific muscles or for the purpose o f variation in a periodized resistancetraining program, it is common to perform different variations of the same exercise (1-3).”
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“The participants started with a standardized, progressive, specific warm-up protocol according to Saeterbakken and Fimland [20].”
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Metadata
- Authors
- Andersen, V., Fimland, M., Brennset, Ø., Haslestad, L., Lundteigen, M., Skalleberg, K., & Saeterbakken, A.
- Affiliations
- Høgskulen i Sogn og Fjordane (NO)
- Norwegian University of Science and Technology (NO)
- Faculty of Teacher Education and Sport, Sogn og Fjordane University College, Norway
- Corresponding author
- Andersen, V.
- Venue
- International Journal of Sports Medicine
- Publisher
- Georg Thieme Verlag KG
- Published
- 2014-09-25
- Volume
- 35
- Issue
- 14
- Pages
- 1196-1202
- ISSN
- 0172-4622 (ISSN-L)
- 1439-3964
- OpenAlex
- W2042373732
- Cited by
- 67
- References
- 0
- Citations by year
- 2026: 8 · 2025: 7 · 2024: 10 · 2023: 2 · 2022: 6 · 2021: 7 · 2020: 10 · 2019: 10 · 2018: 3 · 2017: 1 · 2016: 1 · 2015: 2
- FWCI
- 0.69
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- International Journal of Sports Medicine (publishedVersion)
- PubMed (publishedVersion)
- Topics
- Physical Sciences › Engineering › Biomedical Engineering › Muscle activation and electromyography studies
- Health Sciences › Medicine › Orthopedics and Sports Medicine › Sports Performance and Training
- Physical Sciences › Engineering › Biomedical Engineering › Lower Extremity Biomechanics and Pathologies
- Keywords
- squatting, muscle activation, muscle strength, unstable surfaces, foam cushion, resistance training, biceps femoris, rectus abdominis, erector spinae, external oblique, agonist and antagonist muscles, load reduction, periodization
- MeSH terms
- Adult, Electromyography, Floors and Floorcoverings, Humans, Leg, Male, Weight Lifting, Muscle, Skeletal, Cross-Over Studies, Sports Equipment, Muscle Strength, Resistance Training, Young Adult, Torso
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