1. Department of Physical Education, College of Education, Seoul National University, Seoul, Korea
2. Department of Food and Nutrition, Seoul National University, Seoul, Korea
3. College of Nursing, The Research Institute of Nursing Science, Seoul National University, Seoul, Korea
4. Department of Child Development and Family Studies, Seoul National University, Seoul, Korea
5. Department of Psychology, Seoul National University, Seoul, Korea
6. Institute of Sport Science, Seoul National University, Seoul, Korea