Isokinetic leg strength of institutionalized older adults with mental retardation with and without Down's syndrome.

This study compared isokinetic leg strength of aged individuals with mental retardation (MR) with and without Down's syndrome (DS). Nine subjects with MR and DS (mean age = 61) and 16 subjects with MR but without DS (mean age = 63) performed a leg strength test on a Biodex dynamometer. Parameters measured were peak torque, peak torque percent body weight (ratio displayed as a percentage of the maximum torque production to the subject's body weight), and average power percent body weight. In addition, anthropometric measurements (height, weight, skinfolds, and body mass index) and intelligence quotient (IQ) were also analyzed and compared. The results indicate a significant increase of scores for isokinetic knee extension and flexion in the group with MR but without DS over the subjects in the group with MR and DS. As a group, the individuals with MR and DS tended to be smaller and fatter. No significant difference in IQ was observed between the 2 groups with MR. It was concluded that the strength of individuals with MR but without DS is greater than the group of subjects with MR and DS. When comparing their results to aged individuals without MR, a significant decline in muscle strength can be observed among people with MR.