Document Type : Original Articles


1 a: Department of Physiotherapy, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran b: Student Research Committee, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran.

2 Assistant Professor in Physical Therapy, Department of Physical Therapy, School of Paramedical Sciences, Mashhad University of Medical Sciences , Mashhad, Iran.

3 Department of Physiotherapy, School of Rehabilitation Sciences, Iran University of Medical Sciences, Tehran, Iran

4 Department of Physiotherapy, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran


Background: Abdominal muscles are one of the most important componentsthat provide trunk stability. It has been reported that abdominal musclesendurance can be decreased in patients with low back pain. Tests that canbe used for the assessment of abdominal muscles endurance; include supineisometric 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 verbalencouragement on endurance tests of deep abdominal muscles.Methods: In this two-factor mixed design study, a convenient sample of 40asymptomatic (healthy) participants (20 males and females each) aged between20-35 years was selected. Each subject performed the SICR and SDSLR tests under4 conditions: no feedback, visual feedback, verbal encouragement, and combinedvisual feedback and verbal encouragement. The tests were terminated when thesubject was no longer able to maintain a position. Furthermore, each test wasrepeated twice with 5 min interval and the average time was recorded for analysis.Results: Endurance test time was improved significantly when 2 types of feedbackwere given during the tests (P<0.01). However, combined visual feedback andverbal encouragement had superior effect on endurance test time compared tovisual feedback or verbal encouragement alone (P=0.01).Conclusion: The incorporation of verbal encouragement and visual feedback isan important factor in improving holding time during endurance tasks. Thismay have important implications on endurance training and rehabilitationprogrammes of abdominal muscles.


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