1.    Introduction
Due to technological advances, exercise is considered an individual need and a social necessity, which is one of the valuable factors in society. It can improve physical and intellectual capabilities and eliminate poor mobility. However, obesity and inactivity are two of the most common health problems worldwide, leading to various diseases such as blood pressure, diabetes, heart attacks, musculoskeletal disorders, and more. These health problems definitely affect the normal functioning of daily life. Fat people often believe that their daily energy intake is not higher than that of their thinner counterparts, and they have reported that they are unable to lose weight despite reducing the amount of daily food intake. This claim led to the creation of the hypothesis that obesity is a result of metabolic disorders and incorrect behavioral habits that cause a decrease in energy consumption in people. Therefore, the present research aimed to compare musculoskeletal disorders in the upper limbs of male athletes with non-athlete males who are obese and non-athlete males who are thin.
2.    Methods
This descriptive and analytical study was conducted on Bojnord University students with 15 athletic men, 15 obese men, and 15 thin men in North Khorasan province. The subjects were purposefully selected from the available population and entered the research after completing the consent form to participate in the research and receiving information about the matter and mode of cooperation. The criteria for entering the study in the athlete group were having at least 5 years of training experience and obtaining a position at the level of the city, province, or country in one of the sports fields. In the non-athlete group, not participating in sports was the criterion for entering the study. These people should have a body mass index less than 18.5 (as thin) and more than 30 (as obese). The criteria for not entering the study included the presence of physical and sports injuries or disease. Before the measurements, none of the subjects did heavy exercise, and all the measuring devices used to evaluate the height were tested.
A tape measure with an accuracy of one centimeter was used to measure the height. A digital scale with a measurement accuracy of 100 grams was used to measure the weight, and the body mass index was calculated according to the ratio of weight to kilograms divided by height to the power of two in meters. A flexible ruler was used to evaluate the abnormality of hyperkyphosis and hyperlordosis, and the amount of forward head and forward shoulder deformity was measured using the method of taking pictures of the body profile. All data were analyzed using SPSS version 22 software. Descriptive statistics were used to measure the mean and standard deviation, and inferential statistics were used for one-way analysis of variance and Sheffe's post hoc test at a significance level of less than 0.05.

3.    Results
The subjects were divided into three groups of 15 male athletes (mean and standard deviation: age 25.00±1.92 years, height 174.67±4.83 cm, weight 79.60±1.59 kg, body mass index 25.90±5.19), 15 obese men (mean and standard deviation: age 25.1±86.55 years, height 179.00±4.07 cm, weight 114.13±1.40 kg, body mass index 35.70±4.38), and 15 thin men (mean and standard deviation: age 27.06±3.08 years, height 180.87±4.22 cm, weight 59.80±5.03 kg, body mass index 18.32±1.12). According to Table 1 (Comparison of Musculoskeletal Disorders in the Upper Limb of Male Athletes with Obese and Thin Non-Athlete Males), the forward head angle of obese and thin men was lower than that of athletic men (P=0.001). The forward shoulder angle in athletic and obese men was significantly more than in thin men (P=0.001). Additionally, the angle of kyphosis in male athletes and obese people was significantly higher than in thin people (P=0.001). Furthermore, the angle of lumbar lordosis was higher in obese people than in athletic men, and this angle was determined more in athletic men than in thin people (P=0.001).
4.    Conclusion
Based on the research findings, it can be concluded that abnormalities in the head, shoulders, and spine areas are affected by the type of sport due to repeated movements and techniques. Continuous training of athletes at professional levels can be associated with the risk of skeletal-muscular abnormalities. On the other hand, obesity is also a significant factor in disrupting the human body structure and can lead to the occurrence of these disorders in people.
It has been found that the pressure that high-level athletes put on their bodies during training or competitions can lead to the occurrence of skeletal-muscular abnormalities, but similar disorders and abnormalities may appear in obese people without applying any pressure, indicating one of the dangers of excessive weight gain in people. Furthermore, compared to athletes and obese people, thin people had fewer abnormalities, emphasizing the need for coaches and athletes to pay more serious attention to periodic examination of posture and its angles.

Ethical Considerations
Compliance with ethical guidelines
All ethical principles were considered in this article. The participants were informed about the purpose of the research and its implementation, and they were also assured about the confidentiality of their information. Moreover, they were allowed to leave the study whenever they wished, and if desired, the results of the research would be made available to them.
Funding
This research did not receive any grants from funding agencies in the public, commercial, or non-profit sectors.
Authors' contributions
All authors equally contributed to preparing article.
Conflicts of interest
The authors declared no conflict of interest.