In the last 15 years or so, the establishment of parkour gyms and online searches for them worldwide has been a major cultural shift in parkour and freerunning communities. And, like all major changes, the existence of parkour gyms has become a source of controversy.
On one side of the debate is what I am going to call the purist parkour community. By this I mean that some trainers believe the true, and really only, way to train parkour is with no equipment in dynamic urban environments to strengthen both physical and mental resolve. In addition, indoor facilities arguably offer unnatural training simulation, which does not translate perfectly to outdoor training, potentially offering oversimplified environments. Furthermore, parkour gyms are expensive to both attend and maintain, making them inaccessible for many people who do not have the financial resources for continued indoor training.
All that being said, the existence of parkour gyms has several circumstantial and cultural functions. The most paramount of these functions is safety, as indoor training facilities offer a controlled environment for both new and experienced trainers to learn and develop basic movements with reduced likelihood of serious injury. Indoor training facilities are also particularly useful in countries like Canada with a very distinct winter season, offering a space to train during weather-non-permitting months when the ground and major urban structures are covered in snow and ice. Gyms also provide a central locale for connection and relationship development within the parkour community. In many cities, gyms offer a central hub for the organization of classes, workshops, and jams that bring together trainers of all different skill levels and foster trust and friendship between all.
In short, the controversy surrounding parkour and freerunning gyms is an issue of respect, understanding, and preference. Indoor training facilities have many merits, including offering a safe, year-round, community space, but it must be acknowledged that parkour is an outdoor endeavour that was founded to solely exist in outdoor urban environments. Thus, indoor facilities are reasonable alternatives and serve to foster growth and development of strength and skill, but cannot replace the execution of physical and mental feats in ever-changing urban environments and natural elements.