Abstract: Introduction: In many sports, the body composition of the individual athlete plays an important role. Changes in body composition have been used as information regarding the athlete\\\'s adaptation to different types of training .Aspect such as body composition is of primary importance in success of soccer team. Thus, the aim of this study was to compare body composition of Iranian soccer players in different playing positions during competitions season. Methodology: This was a quasi-experimental research with three experimental groups. In this research 24 players of Pasargad soccer team; defenders (N=8), middles (N=8) and attackers (N=8) were selected randomly as statistical sample. With using In-Body system body composition was measured in the beginning of competition season and after the 15Th match during competition season. Finally, using paired sample T Test (t-student) and ANOVA data was analyzed. Findings: Defender, middle and attacker players showed a significant reduction in BMI during competition season (p<0.05). Also, Middle and attacker players showed a significant reduction in body Fat percentage (p<0.05). Discussion and conclusion: Based on the results of performed research, body composition profiles in soccer players changed during competitions season.

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