NIPH Clinical Trials Search

JRCT ID: jRCT1030220003

Registered date:06/04/2022

A Study of the Effects of Soccer Heading on the Brain Using Pupillometry

Basic Information

Recruitment status Recruiting
Health condition(s) or Problem(s) studiedEvaluation of the brain trauma from heading
Date of first enrollment21/06/2022
Target sample size40
Countries of recruitment
Study typeInterventional
Intervention(s)The subject will be fitted with an electrocardiograph to monitor heart rate and other parameters during the evaluation. Pupillary response will be measured using the NPi-200 pupilometer. Measurements will be taken in a room with sufficient space and height for heading. The room should have an illumination level of 200-500 lux in order to perform pupil measurements in a uniformly illuminated environment. The subject will perform the pupillometry prior to heading in a situation where the subject has not engaged in strenuous physical activity, including soccer, for at least 24 hours. Heading is then performed in the following manner From a distance of 10 m from the subject, a caregiver will head a No. 5 soccer ball (diameter 22 cm, weight 410-450 g) thrown by hand toward the subject's forehead 10 times. Immediately after, pupil response is measured using a pupilometer. After the measurement, the next set is performed immediately without a rest period. After 10 minutes of rest, pupil measurements are taken. 24 hours later, the subject is checked for concussion symptoms such as headache and dizziness. On another day at least one week apart, the subject will perform heading using a lightweight rubber ball (22 cm in diameter, 240-260 g in weight) in the same manner as with the soccer ball, but without strenuous exercise including soccer for at least 24 hours, and pupillary measurements will be taken. Check for the presence or absence of This will be the end of the study. The results of these measurements will be observed prospectively. The subject will be subjected to a head impact by heading. The subject has sufficient soccer experience and is not of an age where heading is restricted by the JFA. The subject will perform 30 headings, which is the standard number of headings performed in one practice session5). Therefore, it is expected that the impact to the subject's head from heading will be minimized. In addition, in this study, heading will be performed twice on two separate days with different types of balls, each time requiring about 15 minutes of time.


Primary OutcomeChanges in pupil response before and after heading.
Secondary OutcomePresence or absence of symptoms typical of concussion, a minor head injury, such as changes in heart rate before and after heading, headache or dizziness after heading.

Key inclusion & exclusion criteria

Age minimum>= 18age old
Age maximum< 30age old
Include criteria1) Healthy adults 2) Age between 18 and 30 years old at the time consent is obtained 3) Have at least 5 years of soccer experience in total
Exclude criteria1) History of brain disease (traumatic cerebral hemorrhage, stroke, brain tumor, infection, autoimmune disease, etc.) 2) History of vestibular dysfunction 3) History of ocular trauma, history of ocular disease with visual dysfunction 4) History of psychiatric disorders 5) Strenuous exercise within 24 hours prior to heading

Related Information


Public contact
Name Junzo Nakao
Address 2-1-1Amakubo, Tsukuba, Ibaraki, Japan Ibaraki Japan 305-8576
Telephone +81-29-853-3900
Affiliation University of Tsukuba
Scientific contact
Name Ai Muroi
Address 2-1-1Amakubo, Tsukuba, Ibaraki, Japan Ibaraki Japan 305-8576
Telephone +81-29-853-3900
Affiliation University of Tsukuba