You can learn from everything you do, including and especially running. If others make jokes about your running, let them. There's nothing you can do about that. You can, however, control your own self-criticism, or at least be aware of it. Running is a way to help yourself and to achieve the things you want. That's hardly trivial. Running clears the mind the way a summer storm blows the smog and haze from the sky. And with a clear mind and strong heart, what isn't possible in this life?