I felt really good because I ran along the coast, and I relieved my many stresses.

I would say that "the run relieved my stress" or "I felt less stressed (because of the run."

I rawent for a run this morning.

I felt really good because I ran along the coast and I relieved my many stresses, which had been at a high level.

So, I reduced my stress is better?

I studied that after for is with - ing but in this case is not. Why?

"I relieved by stress" is best, but it suggests that your stress more or less went away (at least temporarily), whereas "reduced" or "lowered" ("lowered" seems more common, actually) suggests that you may still be under a bit of pressure, just not as much anymore. So it depends on what you want to convey.

Sorry, but I'm not quite sure which part you're referring to, or how it connects to this specific sentence? Quotation marks might also be helpful here.

I'm sorry. I'll write more clearly now. If I use "for", Should I change a verb to -ing? Ex. I woke up early for "making" breakfast.

Thanks, that makes more sense. Off the top of my head, it’s true that we need the “-ing” form after “for,” but in your example, “to” would be better. I associate “for” with adjectival phrases, like “an app for tuning one’s instrument.”