Is creativity good brain exercise?

I have just had a short exchange with a journalist. I sent her a possible story. She decided it might be more lifestyle than health (her area) and sent it on to one of her colleagues. Fair enough but I do think that creativity is good brain exercise and is much part of a healthy life-style as going for a run in the mornings - but that may be because I do not go for runs in the morning. I pedal later in the day, most days.
It is rare for me not to pedal at least once each day. I may not do it tomorrow with a projected temperature of 36'C but then the runners, if they have any sense, will not be out in the heat either. I may do some internal exercise instead.
I admit that pedalling is part of creativity. I sometimes find that a large chunk of idea will fall into place while I am pedalling. If the chunk is the right shape it will stay there. I do not have to worry about remembering it. It will remember itself until I get time to write it down. There are other chunks which wriggle around and teeter over the edge. They may need to be picked up and knocked into shape...a word off here or there or an entire sentence levelled out so that it sits comfortably with the other shapes. It is all exercise.
I think my writing is a bit like building a dry stone wall. I have to find the chunks and work out how the chunks fit into the spaces. It is not like building a brick wall where each brick goes on and gets tapped gently into place with a mortar of words. That is a different sort of exercise.