Hong Kong’s position as the host of one of only five platinum-level half-marathons in the world could be the key to boosting distance running in the city, athletics chiefs said on Friday. This weekend’s Bank of China Hong Kong-Zhuhai-Macau Bridge race was elevated to World Athletics’ highest tier in April, making it the top-rated race in the city. Other platinum events are held in Chonburi in Thailand, Mexico’s Guadalajara, and in the mainland China province of Sichuan and city of Yangzhou. And...