Children with intellectual disabilities (ID) exhibit numerous impairments in different domains of functioning. Alongside impairments in cognitive, social and adaptive behaviour, they also report lower levels of physical fitness at all stages of life (Pitetti and Boneh, 1995, Skowroński et al., 2009 and Van De Vliet et al., 2006). Furthermore, numerous researchers have reported lower performance on standard fitness tests for the assessment of strength, endurance, flexibility and motor coordination, cardiovascular endurance in persons with ID (Chaiwanichsiri et al., 2000, Fernhall and Pitetti, 2001, Graham and Reid, 2000, Guideti et al., 2010, Horvat et al., 1997, MacDonncha et al., 1999 and Skowroński et al., 2009). Lower scores in the domain of physical fitness are associated with limited mental ability and short attention span (Vuijk, Hartman, Scherder, & Visscher, 2010), limitations and impediment in motor development (Frey and Chow, 2006, Hartman et al., 2010, Vuijk et al., 2010 and Westendorp et al., 2011), sedentary lifestyle (Bickum, 1995, Lotan et al., 2004 and Pitetti and Boneh, 1995), and lack of motivation to try one's best during testing (Halle, Gabler-Halle, & Chung, 1999). Test scores are influenced by gender, age, and level of intellectual disability (Fernhall and Pitetti, 2001 and Skowroński et al., 2009). In that respect, children with mild ID have lower scores on locomotor skills than children with borderline ID (Hartman et al., 2010) and athletes with lower ID obtain higher performance scores in motor coordination test (Guideti et al., 2010).
Little information is available on the provision of physical fitness and intervention programs among people with intellectual disabilities, particularly concerning children with ID. Authors Hayakawa and Kobayashi (2011) reported significant improvement in children with ID in the 50 m dash, mean 10 m walk time, 10 m obstacle course walk and a significant increase in the hip joint split angle. Earlier studies done on adults with ID reported beneficial effects of exercise as shown in statistical decreases in individual weight, especially among the mild disability level group, BMI score, and positive improvement in V-shape sit and reach test, sit-up tests. (Wu et al., 2010). Benefits of physical activity were observed in balance, strength, endurance and health self-perception (Carmeli, Zinger-Vaknin, Morad, & Merrick, 2005). Movement difficulties, impossible or impeded coordination of upper and lower limbs significantly reduce activities in children with ID, which is first observed in the family and school environment, and continues throughout adulthood. Reduced number of activities that would enable children to improve existing and develop new abilities may significantly affect their functioning in further everyday life, thereby putting them at risk of declining health associated with low physical fitness (Graham and Reid, 2000, Horvat and Croce, 1995 and Piek et al., 2008).
The aim of our research was to determine whether and to what extent application of different planned activities, i.e. specific exercise program, could affect the development of physical fitness in children with borderline and mild ID.
