Weak Abdominal Strength and Low Hip-and-Trunk Flexibility Increase Low-Back Pain Incidence

Document Type

Conference Proceeding

Publication Date



Weak abdominal strength and low hip and trunk flexibility may be associated with chronic low-back pain (LBP).

PURPOSE: The purpose of this study was to determine if weak abdominal strength, low hip-and-trunk flexibility, or a combination of these two variables increase the incidence of LBP.

METHODS: One hundred and eighty eight adults (95 females, 90 males and 3 who did not report their gender) attending a health and fitness fair were given a low-back health history questionnaire, and their abdominal strength and hip-and-trunk flexibility were measured using an isometric abdominal strength (IAS) test and a hip-and-trunk flexibility (HTF) test. Statistical analysis was conducted using SAS 9.12 and correlations, chi-square and logistic regression analyses were employed to determine the relationships among variables.

RESULTS: The average age for the studied sample was 40 ± 14 (mean ± standard deviation) yr, with an average weight of 73 ± 16 kg and height of 172 ± 11 cm. A total of 52% of the participants reported having suffered from LBP in the past, 18.5% indicated that they suffered from frequent LBP, and 9.1% were currently suffering from LBP. There was an association between weak relative (to body weight) IAS and the incidence of LBP as well as low HTF and LBP, with HTF being a significant predictor for the incidence of LBP. However, the incidence of LBP did not increase if both relative IAS and HTF were low. Furthermore, associations were found among individuals who "suffered low-back pain in the past", "frequently suffer from low-back pain" and "are currently suffering from low-back pain". Participants who indicated they had suffered from low back pain in the past were more likely to report that they also suffered frequently from low back pain (Chi-square = 39.14, p<0.001) and "are currently suffering from low back pain" (Chi-square = 16.80, p<0.001). Participants who indicated they suffered frequently from low back pain were more likely to report they also "are currently suffering from low back pain" (Chi-square = 36.9, p<0.001).

CONCLUSION: Based on the results of this study, both weak relative IAS and low HTF are independent factors that increase the incidence of LBP, but no greater increase in LBP was seen when individuals had both weak relative IAS and low HTF.