The Relationship Between Core Stability & Squat Ratio in Resistance-Trained Males

Tyler Ray, Kent J. Adams, Mark DeBeliso


Background: The lumbopelvic-hip complex, also referred to as the “core”, is composed of every muscle between the knees and sternum. The back squat (BS) and front squat (FS) are both staple exercises that challenge the core in different ways.  Possessing a properly balanced squat ratio (SR = 1-RM FS/1-RM BS; 1-RM = one-repetition maximum) could lead to a more stable core. Objective: This study attempted to determine if there was a meaningful relationship between the SR and core strength (CS) in resistance-trained males. If a strong relation exists between the SR and CS, strength and conditioning professionals would have a readily available assessment tool for examining CS by simply viewing the SR. Method: Twenty-one resistance-trained males (age = 28.3 ± 6.2 years; body mass = 93.1 ± 13.1 kg; height = 181.9 ± 7.6 cm; weight training experience with FS & BS = 6.4 ± 3.7 years) performed CS tests (flexor endurance, extensor endurance, prone bridge, left side-bridge, and right side-bridge), along with a 1-RM in the BS and FS.  An aggregate of the CS test times (CSA) was also calculated for comparison with the SR. A Pearson product-moment correlation coefficient (r) was used to compare the SR with the CS tests and the CSA. Results: The CS test results were as follows (secs): flexor endurance 228.2±93.0, extensor endurance 137.0±28.2, prone bridge 166.7±51.3, left side-bridge 97.36±31.0, right side-bridge 100.2±28.3, and CSA 729.8±165.4. The 1-RM BS, 1-RM FS, and SR were: 157.5±29.7 kgs, 132.2±24.3 kgs, and 0.84±0.06 respectively.  A moderate correlation was found between total CSA and the SR (r = 0.50, CD2 = 0.25, p<0.05).  In addition, a moderate correlation was found between the prone bridge test and the SR (r = 0.49, CD2 = 0.24, p<0.05).  A very strong positive correlation was also found between 1-RM BS and 1-RM FS (r = 0.93, CD2 = 0.86, p<0.05). Conclusions: The results of this study suggest that the CSA and prone bridge test are moderately related to the SR. However, the low coefficient of determination between the SR and CS times suggests that the SR is not a suitable estimate of CS. The very strong relationship between the 1-RM FS and 1-RM BS provides strong evidence for the interchangeable use of these modalities within a resistance training protocol.



Front Squat, Back Squat, Core Strength

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