The comparison of hand grip and trunk muscle strength in active and non-active students with mental retardation and healthy students

Due to special condition of people with mental retardation and their need to have an independent life، muscle strength، is very principal. Various studies have been reported sedentary life style is one of the main causes of physical weakness and health-related problems in these individuals. The purpose of this study was to comparison of hand and trunk muscles strength in athletes and non-athletes mental retarded students and healthy students. Sixty adolescent students (mean age ± SD، 16. 58 ± 1. 13 years) were randomly recruited in this study. This sample is included thirty mental retarded (mean IQ ± SD، 62. 87 ± 5. 15) and thirty healthy age matched students. They were divided into four groups: Non-Active adolescent with Mental retardation (MR)، Active adolescent with mental retardation (AMR)، Non-active Healthy adolescent (HA) and Active healthy adolescent (AHA). The inclusion criteria for mental retardation were IQ between 50 and 70 and for being athletic having more than one year experience in sport fields. Hand grip and trunk muscle strength (back، chest، and shoulders) was assessed by manual dynamometer. MANOVA test was applied to analyze the data at the significant error of 0. 05. All data were analyzed by SPSS، Version 17. The MANOVA results showed a significant difference in hand grip strength between MR and other three groups: AMR (P = 0. 023)، HA (P = 0. 016) and AHA (P < 0. 001). Also in trunk muscle strength significant difference was observed between MR and other groups: AMR (P = 0. 008)، HA (P = 0. 002) and AHA (P < 0. 001)، But no significant difference was found between two groups of AMR and HA in both hand grips (P = 0. 871) and trunk muscle strength (P = 0. 597). Also there is no prominent difference between two groups of HA and AHA in both hand grip (P = 0. 090) and trunk muscle strength (P = 0. 056). The findings identified that sport activities could be an appropriate factor to improve muscle strength in people with mental retardation.