1. Introduction
ealth, as the most important human asset, is a positive aspect of hygiene. This essential human asset includes social, spiritual, emotional, mental, communicative, and physical dimensions. The physical dimension of health (i.e. the desired physical condition in human life) is of particular importance, and its positive and negative changes can affect other aspects of human life [1]. The quality of adolescents’ motor development is an important issue that experts have always considered in physical and motor development. In this regard, basic motor skills are among the characteristics that provide a framework for motor and sports skills in late adolescence, leading to a better quality of daily life activities later in life. 
In stature abnormalities, therapeutic intervention is performed to maintain and achieve proper body mechanics. The goal of correctional programs is to identify, educate, prevent, and improve abnormalities. The first step in identifying the abnormality is to pay attention to the person’s posture and limbs because all musculoskeletal disorders, regardless of the primary cause, manifest their symptoms on the person’s posture.
“Posture” is the skeletal and muscular balance that protects the body’s supporting structures against injury and progressive deformity at work or rest. In such a situation, the muscles are most efficient, and the abdomen and chest organs are in good condition [4]. Improper posture puts pressure on the intervertebral discs and increases tension in the spine’s posterior tissues [6]. If the low back’s curvature is not maintained and the pelvis is not in the proper vertical position, it causes posterior pelvic tilt, and in the long run, causes changes in the lumbar spine [7].
The ability to maintain postural control is an essential factor in performing many daily activities, and motor skills play a significant role in children’s learning ability and provide the basis for the development of other essential learnings such as academic and social skills [8, 9]; as a result, any disruption in the motor skills process causes weakness and problems in the academic, social, learning and individual skills of adolescents [10]. During the developmental stages, motor skills significantly impact motor development throughout life because they allow for better growth by exploring the environment more.
The development of basic skills is the basis of children’s motor development. A variety of movement experiences can provide children with the correct information to develop their perception of the world around them.
Motor skills are broken up into two categories: first, fine motor skills, which include directional, distinct, precise, and skillful movements that require the use of smaller and delicate muscle groups; second, the gross motor skills performed by the large muscles of the body, which include general movement, statics, and balance control [11].
Due to the lack of adequate knowledge and education in adolescents (middle and high school ages), the prevalence of stature abnormalities is common among students [13], while little has been done on elite athletes. On the other hand, anthropometry is used as a suitable tool in biological developmental research, and from the perspective of sports experts, it is an important but controversial indicator for studying the development of motor skills [14]. Regarding musculoskeletal abnormalities, especially in the lower limbs (such as flat sole, hollow sole, knock-knee, bow-leg, lordosis, and kyphosis), the question has always been whether these factors affect motor skills during adolescence or not. This study aimed to investigate the motor skills and postures of adolescents concerning their sports activities.
2. Materials and Methods
This research was a cross-sectional descriptive study, and its statistical population consisted of adolescents aged 12-14 years in middle and high school. This study’s statistical sample included 30 people (13 volleyball players and 17 basketball players) with at least three training sessions per week, and their selection was purposive. 
Before conducting the research, while explaining the necessity and importance of the research to the subjects, a consent form for taking radiographs and another written consent form was taken from all subjects’ parents. Movement motor skills included “grip strength”, “sit-ups”, “Sargent jump”, and “agility (4mX9m) test”, the total scores of which were calculated for each person.
Demographic information of the subjects in the volleyball group (including age 12.92±0.86 years, height 169.23±4.34 cm, and weight 51.69±3.19 kg) and in the basketball group (including age 12.82±0.88 years, height 166.24±4.53, and weight 56.35±6.27 kg) were measured. Independent t-test and Mann-Whitney test were used to compare the variables of motor skills and posture by SPSS software at a significance level of 0.05. In this study, the CSI method was used to evaluate the arch of the sole. Test items included: grip strength, sit-ups, Sargent jumps, and agility (4mX9m) test.
To perform the test, the researcher thoroughly explained to the subjects how to perform each skill; then, the test was presented for each athlete, and he was asked to perform each skill after one observation. To determine the angles and degrees of kyphosis (angles VP-T12, VP-ITL, ICT-ITL) and lordosis (angles DM-T12, DM-ITL, ILS-ITL) in radiographs, the Cobb angle measurement method was used.
3. Results
The results of the independent t-test to compare the variables of motor skills in the two groups of volleyball and basketball confirm that there was a significant difference between the two groups in the Sargent test and the agility (4mX9m) test (P=0.00) (P≥0.05). The results of the grip strength test (P=0.41) and sit-ups (P=0.75) were different, but there was no significant difference between the two groups (P≥0.05).
Mann-Whitney test results to compare posture-related variables indicated no significant difference between the two groups in any of the parameters of varus, valgus, pronation, supination, lordosis, kyphosis, hollow sole, and flat sole (P≥0.05) (Tables 1 and 2). 




4. Discussion and Conclusion
This study compared selected motor skills including “grip strength” (paw), “sit-ups”, “Sargent jump”, “agility (4mX9m) test”, and “posture” of elite adolescent volleyball and basketball players. This study proved that sports, due to activating the muscles, can adequately control stature condition, but motor skills, depending on the nature of each sport, had a higher impact on some parameters. For instance, this study discovered that volleyball players had more impressive explosive power.
Motor skills are a prerequisite for learning special sports skills such as athletics, basketball, volleyball, etc. Numerous factors such as individual differences, musculoskeletal abnormalities, environmental conditions, and gender differences can help develop these skills. However, based on the results and due to the subjects’ abnormalities, their training patterns could be the most crucial cause of the abnormalities. 
Since more physical activity required more training sessions and because all of the athletes were elite, one of the reasons for the increase in some abnormalities might be the number of sessions and training duration [19, 20]. On the other hand, insisting on using a particular group of specific muscles specific to the desired sport and not paying attention to muscles that are not effective in performing techniques may also cause mechanical and structural disorders and create a physically undesirable situation.

Ethical Considerations
Compliance with ethical guidelines
All ethical principles are considered in this article. The participants were informed of the purpose of the research and its implementation stages. They were also assured about the confidentiality of their information and were free to leave the study whenever they wished, and if desired, the research results would be available to them.

Funding
This research did not receive any grant from funding agencies in the public, commercial, or non-profit sectors. 

Authors' contributions
All authors equally contributed to preparing this article.

Conflicts of interest
The authors declared no conflict of interest.

Acknowledgements
The authors would like to thank all of the Aesthetic & Clinical Center, Pouyesh Setaregan Salamat, Tehran.


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