The first phase focused on creating the study groups with different treatment. Three treatment groups were formed.
The first, experimental group (E) included 21 participants, 12 of whom were children with mild ID and 9 with borderline
ID, all of whom participated in the fitness program. The second group, control group 1 (K1), included the same number
of participants (21), 11 of whom were diagnosed with mild ID, 10 with borderline ID. This group did not participate
in the fitness program, but was only involved in the initial and final testing. In order to achieve adequate control
of numerous other factors which may affect the scores, groups E and K1 were evenly matched and pairs were
formed, whereby each child from group E was matched with a child of identical gender, age and IQ from group K1.
Consequently, the two groups were aligned by gender, age and abilities. Children without disabilities made up the third
group, control group 2 (K2), consisting of 45 typically developing participants, who did not participate in the fitness
program, either.
The research was reviewed and approved by the Research Committee. Written consent was obtained from children’s
parents or guardians, as well as from schools administrators, who were informed about the aim and course of this research.