The Effects of Visual Feedback and Verbal Encouragement on Abdominal Muscles Endurance Tests

Background: Abdominal muscles are one of the most important components that provide trunk stability. It has been reported that abdominal muscles endurance can be decreased in patients with low back pain. Tests that can be used for the assessment of abdominal muscles endurance; include supine isometric chest raise (SICR) and supine double straight-leg raise (SDSLR) tests. The aim of this study is to investigate the effects of visual feedback and verbal encouragement on endurance tests of deep abdominal muscles. Methods: In this two-factor mixed design study, a convenient sample of 40 asymptomatic (healthy) participants (20 males and females each) aged between 20-35 years was selected. Each subject performed the SICR and SDSLR tests under 4 conditions: no feedback, visual feedback, verbal encouragement, and combined visual feedback and verbal encouragement. The tests were terminated when the subject was no longer able to maintain a position. Furthermore, each test was repeated twice with 5 min interval and the average time was recorded for analysis. Results: Endurance test time was improved significantly when 2 types of feedback were given during the tests (P<0.01). However, combined visual feedback and verbal encouragement had superior effect on endurance test time compared to visual feedback or verbal encouragement alone (P=0.01). Conclusion: The incorporation of verbal encouragement and visual feedback is an important factor in improving holding time during endurance tasks. This may have important implications on endurance training and rehabilitation programmes of abdominal muscles.