Gyms across Hong Kong were allowed to reopen on September 4, 2020, after being closed for more than 50 days in the second round of social-distancing measures ordered by the city to fight Covid-19. But gyms face heavy restrictions as they get back to business, and many owners and operators say the damage has already been done and is most likely irreparable. The recently formed Hong Kong Alliance of Boutique Fitness Operators, which represents more than 100 locally owned and operated gyms,…