Affiliations: [a] Sports Medicine Research Center, Tehran University of Medical Sciences, Tehran, Iran | [b] Spine Division, Noorafshar Rehabilitation & Sports Medicine Hospital, Tehran, Iran | [c] Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Science, Tehran, Iran
Correspondence:
[*]
Corresponding author: Pardis Noormohammadpour, Sports Medicine Research Center, Tehran University of Medical Sciences, No 7, Al-e-Ahmad Highway, Tehran, P.O. Box: 14395-578, Iran. Tel.: +98 21 88630227 8; E-mail:normohamadpour@tums.ac.ir
Abstract:
OBJECTIVES: To compare the thickness of lateral abdominal muscles
and Cross Sectional Area (CSA) of lumbar Multifidus Spinae (LM) muscles of
competitive off-road cyclists with and without Low Back Pain (LBP). We also
aimed to compare the maximum isometric back strength and endurance, as well
as flexibility of lower back in cyclists with LBP and in the controls. METHODS: The thickness of Transversus Abdominis (TrA), Internal
Oblique (IO) and External Oblique (EO) along with the CSA of LM muscles of
14 professional competitive off-road cyclists with LBP and 24 controls were
measured by ultrasound (US) in hook-lying position on the examination table,
and mounted on the bicycle. In addition, the back strength and endurance of
the subjects and the flexibility of the participants were measured. RESULTS: Data showed a significantly lower thickness of
Transversus Abdominis (TrA) and CSA of LM muscles in cyclists with LBP
comparing to controls in all positions. No significant result regarding the
flexibility of the subjects in case group comparing with the controls was
found (p= 0.674). In addition, it was found that there is no significant
difference in isometric back strength of the subjects between the groups
(p= 0.105). However, we found that subjects with LBP have a lower endurance
in back dynamometry with 50% of their maximum isometric back strength
(p= 0.016). CONCLUSION: In this study, useful information regarding possible
factors associated with low back pain in off- road cyclists was found (lower
thickness of TrA and LM muscles and decreased back endurance).
