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It’s amazing how bureaucrats have behaved towards the fitness industry during the pandemic [THREAD] 
At the beginning some look at exercise as an important potential activity, and gyms as dangerous places to spread the virus, since small closed places can increase airborne transmission after only 15m of a positive case exposure and up to 3h https://advances.sciencemag.org/content/7/1/eabe0166?utm_campaign=TrendMD_1&et_rid=316434840&et_cid=3615969&utm_source=TrendMD&utm_medium=cpc
But gyms are not small
It has been argued that ventilation is increased during exercise
But wearing a mask can be enforced
Moreover, social distancing is easy to carry out in big spaces (and fitness centers have implemented measures that allow 1/ contact tracing due to access control, and 2/ clean and safety measures that allow individuals to exercise safely)
Nonetheless data doesn’t support the exercise/fitness center as a superspreader place (in any country)
https://www.ihrsa.org/improve-your-club/industry-news/university-research-gyms-are-low-risk-for-covid-transmission/ https://www.ihrsa.org/improve-your-club/industry-news/university-research-gyms-are-low-risk-for-covid-transmission/
https://www.ihrsa.org/improve-your-club/industry-news/university-research-gyms-are-low-risk-for-covid-transmission/ https://www.ihrsa.org/improve-your-club/industry-news/university-research-gyms-are-low-risk-for-covid-transmission/
Some publications and research had become popular during this time regardless of their evidence or methodology
Such as the TMA COVID19 TASK FORCE risk chart (TMA is a panel of experts based in Texas)
Or some simulation studies based on time and mobility, and that produces a model that fits to historical data (quick reminder, cum hoc ergo propter hoc) … ( https://www.nature.com/articles/s41586-020-2923-3#Fig3)
In both cases, and mostly, theoretical dangerous places such as trains or buses in which individuals use to spend +15m are missed because of the difficulty to be added into analyses
Exercise can reduce impact of a possible COVID19 (or any other) respiratory infection disease
Exercise is a critical sector to keep population healthy. PERIOD.
