I don't get the logic: singing's not allowed but jogging is?

 One of the courses I do is singing. This last term, there were only 8 of us rather than the usual number of somewhere between 20 and 30 people. 

We had to sit far apart - two metres at least between us to the sides and fore and aft. We all had to face the front and there was no moving about. And we had to keep the same seat week after week. The windows were kept open until we started to freeze, upon which we shut them but kept opening them every 10 minutes or so. As soon as this 'lockdown lite' was imposed, however, the course was cancelled. "Too dangerous," they said. "Have to close it down."

Today, I walked to the university library and went through a huge park to get there. Time and time again, I was either overtaken by pairs and even groups of joggers or had them run towards me. These people are moving through the park, panting heavily as they go. And we walkers are then forced to walk in their wake, breathing in their stale, sweaty air. How the hell can that be safe?? 

As you may know, I go out with a walking group. All our walks in the countryside (not public parks) have been cancelled as a) you can only walk in pairs and b) each pair has to keep 5 metres apart from each other. That's not always practical with walks in woods, especially if there are lots of pathways and you are turning left and right all the time.

I read some official guidelines months ago that stated that whereas walkers had to keep 5 metres apart from each pair, joggers had to keep 10 metres apart and cyclists 15 m apart so that they don't breathe in each what the others have just breathed out. 

Joggers in parks are a danger to other park users. If singing in a well-ventilated room while keeping one's distance from each other is not allowed, then jogging in public should also be banned forthwith.