The choice of a sport is random, and the sport may not have any effect. In this case, Taekwondo may have no effect on the personalities of the students and neither beginners nor advanced students show any pattern in their personalities.
Those entering a sport may show similar personalities, but changes and attrition may cause the pattern to become non-discriminating. In this case, students may choose Taekwondo because it suits their personality, but changes and dropouts will be random, so beginners will show a similar pattern of personality while advanced students will not.
A 1967 study by Kroll and Carlson, Discriminant function and hierarchical grouping analysis of karate participants' personality profiles, in Research Quarterly, noted that combat sports may provide a chance to display prowess or masculinity, to develop self-confidence, release tension, and reduce aggression. Karate (Taekwondo) is suggested as having several advantages as a combat physical education system in that:
- Women may participate.
- As method of self-defense, it may be considered superior to amateur boxing or wrestling.
- It effectively develops certain muscular strengths.
- Emphasis on wholesome character attributes and etiquette help reduce asocial tendencies.