Tehran University of Medical Sciences Acta Medica Iranica 0044-6025 51 2 2013 02 15 101 106 EN Mohsen Rostami Sports Medicine Research Center, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran. AND Spine Division, Noorafshar Rehabilitation and Sports Medicine Hospital, Tehran, Iran. Amir Hosein Abedi Yekta Sports Medicine Research Center, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran. Pardis Noormohammadpour Sports Medicine Research Center, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran. Farzin Farahbakhsh Sports Medicine Research Center, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran. AND Spine Division, Noorafshar Rehabilitation and Sports Medicine Hospital, Tehran, Iran. Mahboobeh Kordi Spine Division, Noorafshar Rehabilitation and Sports Medicine Hospital, Tehran, Iran. Ramin Kordi Sports Medicine Research Center, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran. AND Spine Division, Noorafshar Rehabilitation and Sports Medicine Hospital, Tehran, Iran. 2015 10 11 In light of provided progresses in ultrasound measurements of lateral abdominal muscles, an important role for these muscles, particularly transverse abdominis (TrA) muscle in stability of the spine has been suggested. Some authors have found significant correlations between body mass index (BMI) and thickness of these muscles. The aim of this study was to examine possible association between different methods of measurements of fatness and lateral abdominal muscles thicknesses, employing ultrasound imaging in healthy subjects. Ninety healthy male volunteers aged 18 to 38 (mean= 31.37, standard deviation=5.09) who met our inclusion criteria participated in this study. BMI, skin fold thickness, weight and waist circumference were assumed as the major outcomes for measurement of fatness of the subjects. Employing ultrasound measurements, the thickness of TrA, internal oblique (Int Obl) and external oblique (Ext Obl) muscles were also measured. We found positive significant relation between Ext Obl muscle thickness and all methods of measurements of fatness. Reversely, the results show that Int Obl muscle thickness significantly decreases with the rise of all methods of fatness measurement except weight which had no significant correlation with Int Obl thickness. No significant relation between the TrA muscle thickness and different measurements of the fatness of the subjects were found. In the studies investigate the thickness of lateral abdominal muscles; the authors try to match the participants of different groups of their study regarding the BMI. We found that both waist circumference and skin fold thickness measurements might be assumed as surrogate of BMI, in aim of matching the participants on Ext Obl muscle thickness. https://acta.tums.ac.ir/index.php/acta/article/view/4482 https://acta.tums.ac.ir/index.php/acta/article/download/4482/4337