Joke, maybe sarcasm - the whole basis of allowing people to leave home and the reasons for doing so is just so wishy washy.
What is exercise to one may not be to another - not all of us wrinklies are capable of walking/running/cycling etc. for half an hour to an hour. But half an hour sat on a bench, (or even, dare I say, the beach), is certainly possible, good for our health and I would claim a far lower risk of being contaminated or contaminating others.
Either stop people from leaving their houses except for truly essential reasons or if you are going to say it is ok to leave for recreational, (exercise), reasons then put a time limit on it and enforce social distancing rigorously. The photo I posted was ridiculous, the whole promenade should have been shut down.
I'm not actually sure why you are mentioning exercise TBH as the people this thread is about are clearly not doing that.
I can understand your point about having a rest half way through a walk/run/cycle, I'm sure the police would accept that. ( but not sitting on the beach to rest )
Stopping for a breather seems fair.
The types that are having a BBQ on the beach ( which isn't allowed during the day and on some beaches) are going to spoil it for others that actually want to exercise.