Investigation of the Immediate Effect of Instrument-Assisted Soft Tissue Mobilization on Hand Reaction Time, Neck Pain and Cervical Joint Position Sense in University Student E-Sports Players: A Single-Blind Randomized Controlled Pilot Study

''Electronic sports'' or ''E-sports'' are defined as video games played in a virtual environment in an organized and competitive manner with a specific goal in line with individuals or teams. Although the first steps towards introducing e-sports to the public were taken in the 1970s, it continued to attract attention with the popularity of arcade games in the 1980s. It has also been emphasized that the early 1980s were important years in the history of arcade games. While the first period of e-sports consisted of the times of arcade games, the second period was the period when the use of computers and the internet increased instead of arcade games. It has continued to progress with the variety of games and the variety of internet network technology depending on the developments. E-sports continues to increase its popularity by gaining momentum worldwide with players consisting mainly of the younger population following the development of technology.

Due to the nature of competitive sports, frequent and regular training by e-sports players to increase their performance provides e-sports players with success in the field, but it also increases the time spent in front of the screen. It is known that e-sports players train for an average of 5.5 to 10 hours per day. Therefore, sedentary behavior that develops due to screens is an issue that e-sports players should be careful about. While reasons such as disrupted sleep patterns, increased stress levels and mood changes experienced in the game following increased screen time negatively affect cardiovascular and metabolic health, the fact that e-sports do not require any physical effort also negatively affects the e-sports player's muscular activation. Due to the reasons mentioned, e-sports can cause chronic diseases in the long term.

It is stated that the average career years of a typical professional e-sports players are quite short due to the absolute effort he gives to be the best and to continue in the field. It is expected that this performance of the player, who is expected to make quick and accurate decisions in the moves against the complex visual stimuli presented in the game and the opposing team, will decrease after the age of approximately 24.

The process from the presence of a stimulus to the execution of the action that will occur following the stimulus is called reaction time. Reaction time can also be described as the value taken when a stimulus exceeds the threshold value, when movement is released or at the beginning of the explosive response. Reaction time consists of stages. The process, which starts with the transmission of the sensory stimulus through the receptors, establishes a perceptual link with the motor response and decides to produce a reactive response, and ends with the process of producing a movement that requires muscular force in the perceptual process. Stimuli can be visual, auditory or tactile stimuli. In a study, the reaction time was found to be approximately 190 ms (0.19 sec) for light stimuli and approximately 160 ms (0.16 sec) for sound stimuli. When different studies were examined, the reaction time to visual stimuli was found to be 0.15 s, to auditory stimuli 0.12 - 0.27 s, and to tactile stimuli 0.09 - 0.27 s.

In studies conducted on e-sports players, the most common complaints resulting from long training periods are vision problems and eye fatigue, followed by pain experienced especially in the back, neck and wrist areas. E-sports players perform with poor posture compared to traditional athletes. Games played on mobile phones, especially computer-based games, cause changes in the structure of the spine, pain complaints, movement limitations, and loss of stability and balance. It is argued that the main reason for the pain experienced by approximately half of the players is the anterior displacement of the head due to the prolonged static position spent in front of the screen after a certain number of minutes and the pains brought about by muscle strength imbalances. Professional e-sports players perform up to 400 fine motor movements per minute with minor muscle groups. Clicking/pressing movements originating from controllers used repeatedly for long hours do not remain localized with the fingers and can cause pain or injuries in the hand-wrist, elbow, shoulder and cervical region. Neck pain in particular becomes chronic over time. This is because e-sports players train for long hours and compete in competitions in a bad posture where the head is in an anterior tilt position. There are studies in the literature showing that cervical joint position sense is adversely affected in chronic neck pain.