The Impact of Visual Impairment on Human Development

by. Tommy H. Firmanda
School of Education, Flinders University

Introduction

In general, a person with visual impairment is known as an individual who has weak eyesight or accuracy of vision is less than 6/60 (20/200) after correction or no longer have a vision. According to Silberman, Bruce, and Nelson (2004), there are two standard categories of visual impairment. First, a legal blindness which is defined as someone who has a central visual accuracy of 20/200 (6/60) or less, after the correction. If after someone wearing glasses or contact lenses, he has an accuracy of 20/200 (6/60), this means that he can see an object at a distance of 20 feet (6 meters), while people with normal vision can see from a distance of 200 feet (60 meters). Also, if a person has a visual field of 20 degrees or less, then he can be considered as totally blind. In this category, it also including someone with normal visual acuity but has visual field less than 20 degrees or less, or in other words no side vision (tunnel vision) (Silberman et al., 2004). Second, persons with low vision is individuals who although  have already being corrected, still presents damages and disruptions in terms of visual acuity (between 20/70 until 20/200), the field of vision (20-40 degrees or less), sensitivity to light, and the ability of contrast, but still has a residual capability eyesight which can be optimized using visual compensation strategies, low vision aids, and environmental modifications, to read, write and mobilize although limited in its use (Brilliant & Graboyes 1999; Corn & Koenig, 1996; cited in Silberman et al., 2004). Currently, the term “low vision” including moderate visual impairment combined with severe visual impairment, can be seen as follows:

The level of blindness based on the vision acuity

No	Category of Visual Acuity (after corrected)	WHO Standard Definition
1	6/6-6/18	Normal
2	< 6/18-6/60	Visual Impairment/ LowVision
3	< 6/60-3/60	Severe Visual Impairment/ Low Vision
4	< 3/60-1/60	Blind
5	< 1/60-PL	Blind
6	NPL	Totally Blind

Based on the data from WHO (2014), approximately there are 85 million people who are identified to living with blindness and visual impairment throughout the world which is around 39 million are blind, and the rest (246 million) have low vision. In fact, around 90% of people with visual impairment are living in developing countries (WHO, 2014).

This condition has an impact on the development of people with blind and visual impairment. It results in the child's gross motor skills or mobility skills, social, cognitive and conceptual perception being affected. As Lowenfeld (1981; cited in Silberman et al., 2004) stated, visual impairment can have an impact on the range and variety of experience, mobility, and social interactions. This paper aim is to explore Visual Impairment and the effects on range areas of development, so challenges and learning needs can be understood.

Overview of Vision Impairment

In general, people with visual impairments still has a residual vision that can be used optimally. In fact, individuals with visual impairments who declared "totally blind", are less than those who still have some good vision. Based on the latest data, the number of people with low vision is three to four times the blind persons, excluding those with uncorrected refractive errors (Foster & Resnikoff, 2005; WHO, 2014). The leading causes of global blindness are a cataract, glaucoma, corneal scarring (from various causes), retinal diseases (age-related macular degeneration, retinitis pigmentosa), diabetic retinopathy, congenital abnormalities, and hereditary retinal dystrophies (Foster & Resnikoff, 2005; Gilbert & Foster, 2001; Kingman, 2004), prenatal factors such as infections and abnormalities, hypoxia, chromosomal and genetic defects, and parental alcohol and drug abuse (Silberman et al., 2004). In addition, Gilbert and Foster (2001) also mentioned that the leading causes of blindness in developing countries are corneal scarring from measles, vitamin A deficiency, the use of harmful traditional eye medicines, and ophthalmia neonatorum, while in developing countries, the primary cause of blindness are lesions of the optic nerve and higher visual pathways predominate. Even though children and adolescent with low vision still have a useful vision, some development is still affected by the limitation of the vision as well as those children with the blind condition. Research had indicated that low vision does affect the children and adolescents’ sensorial, physical, psychological development and social well-being (Rainey, Elsman, Nispen, Leeuwen, & Rens, 2016). Moreover, there a variety of difficulties related to these limitation of people with visual impairment such as mobility, daily activities, and physical performance (Salive et al., 1994), social function as well as health-related quality of life (Campbell, Crews, Moriarty, Zack, & Blackman, 1999; Nyman, Gosney, & Victor, 2009), facing a risk to get falls or fracture (de Boer et al., 2004), and reading development (Thurston, 2014),. Although the number of children and adolescents with visual impairments and blindness is much less than adults, they tend to potentially have a greater lifelong impact of the disorder. A discussion about the problems associated with obtaining certain life skills for children with visual impairment will follow next.

Physical and self-help skills

In this matter, the physical limitations arise as a result of weakness or loss of vision. Basically, a vision was instrumental in the development of children, because they will be motivated to see the various objects in the surrounding areas by approaching the object. As a result of limited vision, many blind children have poor motor coordination, tend to be unmotivated to move, and may have limited opportunities to reach, grasp objects, and release it (Silberman, 2000; cited in Silberman et al., 2004). In addition, blind children also experience delays in the development of fine motor skills or has limitations of using their arms, hands, and fingers that hamper daily living skills such as eating, dressing, and self-care (Jacobs, Hammerman-Rozenberg, Maaravi, Cohen, & Stessman, 2005; Silberman et al., 2004). This problem will continue to occur until old age, in line with a study which revealed that eye disorders are significantly increasing dependence on others to perform ADLs (Marx, Werner, Cohen‐Mansfield, & Feldman, 1992). Furthermore, visual function is significantly associated with physical function, especially for mobility (Salive et al., 1994). An example regarding physical and mobility issue:

“A boy who is blind does not know how to get to his cubby or to the teacher’s desk without individuals orienting him to the classroom. Outside of the classroom, he does not know how to go to the lunchroom or gym, and on field trips, obstacles are not apparent to him, so he is not free to explore the environment without another person going with him” (Silberman et al., 2004, p. 436)

A mobility instruction plays a significant role in overcoming the mobility problem. To engaged and move to other places efficiently, it contains two elements, namely orientation and mobility elements. Orientation is the process of using the senses which still serves to define the position of self and its relationship with the objects that exist in the environment, while mobility is the ability to move and migrate safely, independently, and purposefully in an atmosphere (Pagliano, 2005).  Pagliano (2005) also suggest that the training of O and M needs to start as early as possible in conjunction with the development of body image and concept. Although the impact of O and M training does not occur directly, which means it needs time to obtain the skills, we need to consider about the measurement of the mobility performance after training (Soong, Lovie-Kitchin, & Brown, 2001). Other strategies which can be used to improve the physical performances is vision rehabilitation. Despite its small outcomes of the reconstruction (Lamoureux et al., 2007; McCabe, Nason, Demers Turco, Friedman, & Seddon, 2000), this strategy gives hope for the improvement to perform daily living skills. As Horvat et al. (2003) indicate, the Orientation and Mobility (O&M) for individuals with visual impairment rely on the use of sensory information obtained from other senses (exclude sight) to start the movement which is affected by changes in center of gravity and the support base.

Experts who can help people with visual impairment, in this case, is the Orientation and Mobility Specialist. COM is a Certified Specialist who has completed their education at the undergraduate or graduate level and has received national certification from the Academy of Professional Certification of Vision Rehabilitation and Education (ACVREP).A COMSs' duty is to help those who has visual disturbances or other disorders associated with difficulties in mobility, to learn to adjust and mobile safely and efficiently in a variety of settings (Koenig & Holbrook, 2000; cited in Silberman et al., 2004).

Sensory skills

Persons with a visual impairment may have different responses to sensory information compared to normal development on the average age. Silberman et al. (2004) mentioned some of the responses of children with visual impairment, such as having a poor posture due to lack of role model through direct visual examples, lack of interest to do something because of limited vision, but can be overcome by expanding sensory experience, lack of visual stimulation so that the children often do their own self-stimulation, and often using other senses which are still functioning normally (e.g. hear or tactile) to obtain information. In fact, people with visual impairment prefer to use the other senses instead of their vision, although they still have some vision (Colenbrander & Fletcher, 1995). For example, listening to the radio rather than reading the newspaper or watching television. In some cases, using other senses has made those senses superior to sight people. For instance, research indicates that tactile spatial acuity in blind Braille readers is excellent compared to sight people (Van Boven, Hamilton, Kauffman, Keenan, & Pascual–Leone, 2000).

Regarding education, students with visual impairment often receive incomplete information and tend to use sensory feedback to focus or compose him/herself. As a result of problems in sensory processing, these students tends to experience a difficulty to perform functional and academic tasks. A study by Fraser and Maguvhe (2008) has revealed that the result of a lack of vision, lack of confidence, lack of motivation in children with visual impairment and blindness include a very rarely involved in practical work and field trips. Practical activities were limited to very straightforward and basic exercises that provide little intellectual challenge and do not call for advanced problem-solving skills. Also, students also have limited access to computers, encyclopedias, reference sources and relevant publications. Although not all type of visual impairment needs attention, early intervention and sensory stimulation are necessary to be considered.

Cognitive skills and Academic

The limitations of vision could impact to a wide range of aspects related to cognitive development. Students with blind and visual impairment tend to have difficulty to imitating or copying others, cannot integrate specific things into a whole which has a particular meaning, lack of ability to confirm or remember and emulate a similar experience. Furthermore, these students have a slow learning speeds and need more time to acquire new skills or working on something (Silberman et al., 2004). Additionaly, Strickling (2010) divide the cognitive domain into five aspects namely construct of the world, object permanence, causal relationship, constancy, and conservation. First, regarding construct of the world, children with blind and visual impairment have difficulties in verifying the general information. Thus, they have a different perception of reality than sighted children. The process of concept building and problem-solving also tend to be harder to develop and less profitable for them. Second, Children with visual impairments experienced delays in getting permanent object capabilities. Objects permanent requires a stable visual field capacity as well as doing other conceptual tasks. This is because they do not have the ability to reach objects and need the support of sound cues. Third, children with visual impairments tend not to understand the capacity to make a change because there is no motivation to take action. This is because they can not see the results of their work. Forth, inability to observe objects from different orientations lead to the emergence of difficulty to manipulate objects or to recognize patterns and duplicate it. Fifth, Children with blind tend to have difficulties to understand the concept of similarities and differences as well as a lack of generalization and association skills, as a result of the limitations to explore objects and cause the classification errors. Last, regarding conservations, delays in a preservation of substance, weight, volume, length and liquids often occur.

To assure that the appropriate testing accommodations and modifications are made, a screening test such as a Functional Vision Evaluation (FVE) and Learning Media Assessment (LMA) which runs by the relevant teacher, must be completed before any assessments are conducted (Landa-Vialard; Silberman et al., 2004). To overcome the challenges to participating in the academic areas, Pagliano (2005) suggests an appropriate low vision device check the environments such as additional lighting, modify font size, contrast, preferential seating, reduce visual clutter and frustration and increase opportunities for academic success for children with low vision. While for children with blindness, we need to build lesson based on the children’s experiences, provide learn by doing approach, use real objects, provide opportunities for overlearning, and help child generalize transition to other settings. Indeed, he also points out that students with visual impairment need an extra time. Also, Holbrook and Koenig (2000; cited in Pagliano, 2005, p. 352) suggest that “students with vision impairment be held to the same academic and social standards as their sighted classmates to prepare them for adult life”.

Communication and language skills

Vision and language have played an essential role in the development of communication skills. Language is used to interact and build a relationship with other people, while vision (e.g. eye contact) is used to accommodate the communication Children with visual impairments and cerebral palsy has more difficulties with strong and nonverbal forms of communication (Silberman et al., 2004). Moreover, Silberman et al. (2004) also stated that children with visual impairments have more difficulties with powerful and nonverbal forms of communication.

Basically, speech and language in children with visual impairment are almost the same as children without disabilities, although in some cases, it has been found that the achievement of language and communication skills tends to be slow or even has a communication disorder such as using the word inappropriately  (James & Stojanovik, 2007). This is due to the limited capabilities of mobility and lack of visual stimulation so that the experience is limited and affected the ability of language (Scholl, 1986; cited in Silberman et al., 2004). Despite limited experience, the language may be delayed but not distorted. As Silberman et al. (2004) said, there are some characteristics of children with VI related to language and communication's issues, such as being able to respond appropriately and enjoy two-way verbal communication, vocabulary build through direct experience, challenging and slow in understanding the abstract concept. However, they may also have difficulties to initiate and engage in meaningful conversations, which due to their narrow range of “topics of interest” (Silberman et al., 2004). Silberman et al. (2004) recommend to use universal modes of communication and adapting communication to learner’s pace to facilitate the improvement of communication skills.

Social and interpersonal skills

Some research indicates that many children and youth with visual impairments are socially isolated, have smaller social networks due to their limited opportunities to engage in many social activities, which this means that they require targeted interventions in some areas in order to interact with other peers (Silberman, 2000; cited in Silberman et al., 2004).  This limitation is because they have difficulties to make an eye contact. Thus they are unable to respond to social signals and recognizing facial expression (Silberman et al., 2004).

Silberman et al. (2004) state that there are some characteristics of children with visual impairment related to social difficulties, including “difficulty in observing, organizing, and synthesizing the environment; imitative and make-believe play may be delayed but enjoys playing with other children, requires a variety of opportunities to learn and to generalize; needs feedback to understand and comprehend some social situations, initiates interactions with adults and children, shows social curiosity; is curious about environment, demonstrates empathy and able to comprehend another’s feelings” (p. 438). Children with VI also tend to have limited flexibility in managing changes in routine (Silberman et al., 2004).

To be able to interact effectively, social skills need to be taught to children with visual impairments, under monitoring by teachers or professionals to ensure they successfully learn these skills. Professionals in charge to identify appropriate strategies for teaching social skills, provide consistent support and follow their development over the long term period because short-term intervention seems to do not have an effect on social skills (Kekelis, and Gaylord-Ross, 2001; cited in Celeste, 2007). However, need to be noted that although they have acquired the social skills, they might still face difficulties to build a relationship, as a result of insufficient situational cues, the lack of honest feedback from interactants, inappropriate behaviors of sighted people, and negative attitudes toward visual impairment in society. By negative interactions with others without disabilities (Kim, 2003).

Vocational skills

The number of people with a blind and visual impairment in the workforce throughout the world is generally lower than those without disabilities (Wolffe & Spungin, 2002; cited in La Grow, 2004). In fact, the majority of developing countries has reported that only approximately a quarter of working age are employed, while the rest (70-75%) are unemployed and underemployed (Bruce, McKennell, & Walker, 1991; Hagemoser, 1996; Hanye & Crudden, 1999; Kirchner, 1988; Leonard, D'Allura, & Horowitz, 1999; McNeil, 1996; Roy, Dimigen, & Taylor, 1998; Tillsley, 1997; cited in La Grow, 2004). La Grow (2004) identify the degree of severity, gender, and the presence of additional conditions as the cause of lower rates of employment. Other has also identified out-of-date or remote assistive devices and materials, lack assistance, transportation problems and environmental barriers, poor remuneration, job status, discrimination, lack of funds or time, housing issues, and less training opportunities as work walls (Wolffe, Ajuwon, & Kelly, 2013). In addition, a negative attitude toward people with sensory disabilities, especially among woman and minority group, still exists in the community at the moment (Pagliano, 2005). He suggests that by teaching pre-employment skills, promoting social interaction, and providing job training as a solution to overcome the issues (Pagliano, 2005).

Conclusion

This essay has described the impact of visual impairments on some of the developmental aspects. An overview of this disability was presented, as well as the issues related to VI in terms of physical and mobility, daily living skills, sensory issues, cognitive and academic, communication and language skills, social interaction and vocational skills. Although there are many solutions to overcome the educational and developmental issues, considerations when implementing the management strategies needs to be a concern regarding assessments, environmental modification, assistive technology, classrooms adaptation and core curriculum. This essay has a limitation. All procedures describe in this paper might only reflect a practical use. However, further, improvement is required in the future.

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The Role of Physical Activity and Obesity among Children and Youth with Intellectual Disability

by. Tommy H. Firmanda
School of Education, Flinders University

Obesity is one of a health problem that currently has become the public health concern, because of its trend of the increasing number of people with obesity among children and adolescents each year. Several studies have indicated that the prevalence of overweight and obesity is higher among children with intellectual disability/developmental disabilities than in the general population (Hsieh, Rimmer, & Heller, 2014; Lin, Yen, Li, & Wu, 2005; J. H. Rimmer & Yamaki, 2006). Overweight and obesity are defined as “abnormal or excessive fat accumulation that may impair health” (WHO, 2016). Research suggest that more study needs to be conducted on successful weight reduction strategies for obese persons with ID. Adolescent need to engage with 60 minutes daily physical activities to get a better health and behavior outcomes (Strong et al., 2005). Although obesity has become a major health issue among children and adolescents with intellectual disability, a positive expectation from the implementation of physical activity as an accessible and effective prevention solution still exists. The purpose of this paper is to presents an overview of current studies related to a health-related problem of overweight and obesity among children and adolescents with intellectual disability. It then will generally describe the role of physical activities in promoting health. Last, it will discuss the relationship between physical activity and overweight and obesity and its role in promoting health among these children with ID.

The effect of unhealthy lifestyle among youth with ID has become a concern for the last few decades. Unhealthy lifestyle is associated with health problems which could lead to some chronic diseases as a secondary health condition among youth with an intellectual disability. Van Itallie (1985) reported that the relative risk of hypertension, hypercholesterolemia, and diabetes is likely to be higher in overweight adult under 35 years old. In line with the findings, cardiovascular has also become another risk facing children and youth in general population (Freedman, Dietz, Srinivasan, & Berenson, 1999). Meanwhile, among youth with intellectual disability (ID), a higher number of obesity-related secondary conditions bringing them to greater health problems during their transition into adulthood (Rimmer, Yamaki, Lowry, Wang, & Vogel, 2010). As Rimmer et al. (2010) mentioned that these obesity-related secondary conditions including hypertension (high blood pressure), hypercholesterolemia (high blood cholesterol), diabetes, cancer, depression, fatigue, liver or gallbladder problems, low self-esteem, preoccupation with weight, early maturation, and pressure sores. Moreover, a psychological effects also found in some studies such as reducing quality of life (Hughes et al. 2006; cited in Rimmer et al., 2010), difficulty building relationships with peers (Gortmaker et al. 1993; Koplan et al. 2005; cited in Rimmer et al., 2010), as a result of discrimination among youths with disabilities. It was been reported that the number of mortality was significantly higher for people with disability (Yang et al. 2002; cited in C. Melville et al., 2008). However, this study only involved people with Down Syndrome, which means that these results can not be generalized to all persons with intellectual disability. In addition, many types of research have analyzed the impact of obesity on longevity, and conclude that the life expectancy among obese people will decline significantly (Olshansky et al., 2005). Unhealthy lifestyle such as eating habits and physical inactivity might contribute to increase the risk of people with intellectual disabilities developing obesity.

Deckelbaum and Williams (2001) assert that one of the causes of obesity is the increased supply of food and calorie intake, but it is not balanced with appropriate levels of physical activity (decreasing). Physical activity is the movements of the body as a whole (muscle activity) which have an impact on the rise of energy consumption (Caspersen, Powell, & Christenson, 1985; Must & Tybor, 2005; Ortega, Ruiz, Castillo, & Sjöström, 2008). Indeed, studies have recommended school-age youth to participate in an average of 60 minutes or more per day of at least moderate to vigorous physical activity that is fun and age developmentally appropriate (Janssen & LeBlanc, 2010; Strong et al., 2005). It is known that physical activity in appropriate amounts, is needed to beneficial changes in the body health such as body composition,  bones health, fitness, muscular strength, endurance, and reduce overweight as well as contribute to prevention or delay of chronic diseases  (LeMURA & Maziekas, 2002; Strong et al., 2005). Furthermore, not only derive health benefits, its also includes improved gross motor function, and high levels of participant or parent satisfaction for children and youth with intellectual disability or developmental delay (Johnson, 2009).

Even though many studies has proven the benefits and positive effects of physical activity to improve the development, quality of life, future health and life outcomes (Anderson, Bedini, & Moreland, 2005; King et al., 2003) for children and youth with disabilities, the amount of participation is remaining lower than those children without disabilities. Based on the systematic review of some resources related to this issue, Shields, Synnot, and Barr (2012) has identified some barriers and facilitators to physical activity perceived by children with disabilities. The barriers were divided into three categories namely personal, social environment and policy barriers. First, personal barriers to participation include lack of knowledge about the exercises and skills (physical and social), the child's preferences for activities other than physical activities, and feeling of fear. Second, social barriers include parental actions, behavior or concerns, a lack of friends to participate with or unsupportive peers and negative societal attitudes to disability which is not only from peers but also teachers’ attitudes. In terms of environmental barriers, the barriers include inadequate, inaccessible or inconvenient facilities and a lack of transport to access the facilities. Last, the policy or program barriers include lack of appropriate physical activity programs,  lack of staff capacity, and cost, and negative attitudes towards working with children with disability. Another factor related to the participation of children with disabilities is the facilitators of those personal, social environment and policy barriers (Shields et al., 2012). First, personal facilitators included the child's desire to be active and fit, practicing skills and gain competence, and having fun. Second, social facilitators included involvement of peers, family support, opportunities to access the activity, child’s motivation, interest, positive encouragement, the family’s role (parent or siblings) in facilitating and involve in the physical activity. Third, environment facilitators included accessible facilities and proximity of location and facilities. Last, in terms of policy and program, a structured, varies, non-competitive, in a small group or individual and age-appropriate programs provided, and skilled staff and information seen as facilitators. Similarly, Bodde, Seo, and Frey (2009) conclude that the main barriers faced by persons with disorders of intellectual accessing physical activity is transportation issues, cost limitations and the lack of awareness of choice, negative support from the caregiver and authority figures (such as teachers, coaches and parents) and the lack of clear policies to engage in routine activities in the residential and day service programs. It should be noted that the intervention program would be difficult to be implemented if these obstacles, including the association between each aspect, can not be clearly understood.

Interestingly, in terms of the correlation, there are a lot of studies investigated the relationship between physical activity and overweight, which include gender difference as a consideration, reported inconsistent findings. Rauner, Mess, and Woll (2013) conclude that the interaction between physical activity and overweight is still unclear, due to the variety of method, measurement instruments, parameters, and other aspects which make the results inconsistent. For example, some studies were found the correlation between physical activity and overweight, while in contrast, other studies found that there were no relationships between physical activity and overweight. Additionally, in terms of the effect, there are not much research investigated the effectiveness of physical activity interventions to reduce the risk of overweight or obesity. This has led to the assumption, despite having been proven to have positive effects on health, whether physical activity is directly related to obesity and whether the risks would mean overweight and obesity can be prevented by sufficient physical activity is still in doubt. A review on the effects of exercise interventions for children and adolescents who are overweight, confirm that exercise can reduce body fat percent of overweight and obese children and adolescents (Kelley & Kelley, 2013). Another research shows that Physical Activity (PA) intervention was working on reducing gestational weight gain (GWG) in obese pregnant women (Renault et al., 2014). Assuming that regular physical activity and exercise has the same effect, these studies indicate the role of physical activity in the prevention of weight gain. However, little evidence exists that physical activity or exercise influencing weight loss. Several studies show that there is no significant change in weight after following PA interventions (Church et al, 2010; Bateman et al, 2011; cited in Swift, Johannsen, Lavie, Earnest, & Church, 2014). Similar to those studies, there are no significant differences between implementing PA and either combines with caloric restriction or not tp achieve weight loss (Miller et al, 1997; Wing, 1999; cited in Swift et al., 2014).

In spite of no clear evidence about the influence of physical activity on weight loss and prevents obesity, evidence that physical activity has a positive impact on health can be the basis for implementing the PA programs. A literature review by Harris, Hankey, Murray and Melville (2015) on some studies related to the PA interventions for youth with intellectual disability revealed that there was no significant impact of physical activity (PA) interventions on preventing weight gain. In contrast, one study shows that a long term PA program including an aerobic or physical exercise for overweight to obese women with ID can be used as an effective plan for reducing subcutaneous fat mass (Merrick, Bachar, Carmeli, & Kodesh, 2013). Moreover, a study shows that healthy exercise program had a positive effect on the fitness of people with ID, although in this study also found that the highest effectiveness in this program on weight loss was more visible in those with mild ID (Wu et al., 2010). Besides physical activity, many types of research were conducted to measure the intervention effect to weight loss of persons with intellectual disability. A restricted diet including consuming high volume, low-calorie foods, and beverages, as well as using meal-replacement has proven to have a contribution to weight loss in children with ID(Saunders et al., 2011). In fact, a study by C. A. Melville et al. (2011) has confirmed that a diet intervention (i.e. TAKE 5) is effective intervention to reduce weight among adult with an intellectual disability. Based on the finding results of such research, we still believe that interventions to overcome overweight and prevent obesity may show more positive results among people with or without intellectual disability.

Although studies on the relationship between physical activity (PA) and obesity among children and adolescents with intellectual disorders and the effectiveness of the PA programs to prevent excess weight has not shown a definitive results yet, the positive effects on health need to be considered as a reasonable reason, so that the PA programs still can be implemented to address obesity-related health problems. Therefore, the role of prevention and management of obesity in children and adolescents with an intellectual disability through a structural, accessible and effective physical activity are still important. It is recommended to not only focus on physical activity but also all the elements, such as eating habits and environmental supports (supportive community network), also needs to be implemented to prevent overweight and obesity among children and adolescents with ID. In addition, the need for further research to investigate the role of physical activity associated with effective interventions to prevent health problems caused by obesity is also highly recommended.

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