I too have only experienced it sporadically since beginning to run during the pandemic. Perhaps it is a function of time and a certain level of exertion; when it happens it is rather like a flow state that arrives unbidden, and doesn’t last the whole run. I have never run more than 13km, and would have averaged more like 6-7km per run, so hang in there, I suspect as your fitness improves you will experience it.
I too have only experienced it sporadically since beginning to run during the pandemic. Perhaps it is a function of time and a certain level of exertion; when it happens it is rather like a flow state that arrives unbidden, and doesn’t last the whole run. I have never run more than 13km, and would have averaged more like 6-7km per run, so hang in there, I suspect as your fitness improves you will experience it.