Background The influence of various physical exercise frequencies on postural balance and muscle performance among young persons with intellectual disability (ID) is not well understood.

Method Cross-sectional data from 26 elite athletes were compared with 37 students at a sports school and to 57 students at a special school, all diagnosed with mild to moderate ID and with different exercise frequencies. Data were also compared with a group of 149 age-matched participants without ID.

Results There were no significant differences in postural balance between young ID groups regardless of physical exercise frequency, all of them had however impaired postural balance compared to the non-ID group. The group with high exercise performed better than the other ID groups in the trunk muscle endurance test.

Conclusions It appears as if physical exercise frequency don’t improve postural balance but endurance in the trunk muscles for young persons with ID.