Lumbar Muscle Activation Pattern During Forward and Backward Walking in Participants With and Without Chronic Low Back Pain: An Electromyographic Study

Objective: The purpose of this study was to investigate the electromyographic activity of lumbar multifidus (MF) and erector spinae (ES) muscle during forward walking (FW) and backward walking (BW) in participants with and without chronic low back pain (CLBP). Methods: Twenty-one patients with CLBP were recruited from outpatient department of Centre for Physiotherapy and Rehabilitation Sciences, Jamia Millia Islamia. Twenty-one age-matched healthy controls without CLBP were recruited from community. Maximum voluntary isometric contraction (MVIC) was quantified for MF and ES using standard guidelines. Electromyographic activity of MF and ES was recorded using surface electrodes during FW and BW on a motorized treadmill, which was later normalized by respective MVIC's of each muscle. Results: Muscle activity (in percentage MVIC) was determined to be higher for both the muscles during BW. Activity of MF muscle was significantly higher in CLBP patients compared with healthy controls (P < .04). Electromyographic activity of MF and ES was significantly increased during BW (MF: P < .001; ES: P < .001) compared with FW in both healthy and CLBP groups. Conclusion: BW leads to greater activation of the paraspinal muscles. Along with global extensor (ES), activity of core extensor (MF) is also higher during BW than FW in both healthy participants and CLBP patients. BW is a more favorable aerobic activity to enhance lumbar paraspinal recruitment. These findings may have important clinical implications in the rehabilitation of CLBP.