Editor's Note: Is the marathon a sport for all or just a carnival for the middle class? Do so many roads need to be closed and so many volunteers posted,which disrupt the public order, to ensure a marathon race proceeds smoothly? Two experts and a marathoner share their views on the issues with China Daily's Wu Zheyu. Excerpts follow:

Don't ignore the business potential

Yi Jiandong, director of sport industry and health management program at Peking University's National School of Development