Surface electromyography analysis of the free, smith and split squats performed by strength trained males

Issue: Vol. 5 No 3

Published by Journal of Fitness Research, 08/12/2016. Volume 5.3

Tags: Biceps Femoris , Lateral Gastrocnemius , Muscle Activity , Squat Type , Strength And Conditioning

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  1. Eric Chauhan
    Faculty of Arts & Sciences, Edge Hill University
  2. Craig Bridge
    Faculty of Arts & Sciences, Edge Hill University
  3. Benjamin Hammond
    Faculty of Arts & Sciences, Edge Hill University
  4. Pascual Marques-Bruna (Corresponding Author)
    Faculty of Arts & Sciences, Edge Hill University


Introduction: Squats recruit a large proportion of the body’s muscular system and provide a foundation for strength training programs for athletes. However, our understanding of electromyographical activity in variations of the high-bar back-squat, notably the split squat, is limited. Therefore, this study aims to investigate surface electromyography (EMG) in the free, Smith and split types of squat.

Method: A randomised sample of 10 healthy strength-trained males (mean ± SD age, 20.3 ± 0.5 years;height, 1.7 ± 0.6 m; mass, 78.1 ± 9.5 kg; strength training, 2.5 ± 0.5 years) performed 3 repetitions of each type of squat at 75% of their one repetition maximum. A Noraxon EMG - Raxon system was used to collect peak EMG, root-mean-square EMG (RMS EMG), and integrated EMG (iEMG) data for the eccentric and concentric phases of the squat. EMG data from the free and split squats were normalised to the Smith squat. Two-way ANOVAs were used for the analysis of type-of-squat and phase-of-squat (p ≤ 0.01).Results: Statistically significant effects for type-of-squat were found for peak EMG and iEMG of the bicep femoris (BF), lateral gastrocnemius (LG) and tibialis anterior (0.001 ≤ p ≤ 0.003), and for RMS EMG of the BF(p = 0.002) and LG (p = 0.001). Significant differences in phase-of-squat were found for peak EMG and RMS EMG of BF (p = 0.001).

Discussion: The split squat elicited higher BF and LG muscle activity compared to the free and Smith squats. The findings suggest that the split squat effectively stimulates the BF and LG muscles and should consequently form an integral part of strength programs for athletes.

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Article Title

Surface electromyography analysis of the free, smith and split squats performed by strength trained males

Journal Title

Journal of Fitness Research Volume 5.3

Online Publication Date


Author Names

Eric Chauhan
Craig Bridge
Benjamin Hammond
Pascual Marques-Bruna (Corresponding Author)
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