For remedy, i just do regular foam rolls pre and post run.
I, personally, think it is because of my stride. Sometimes i feel like i cant find my stride; there are times wherein my body's so stiff and there are times wherein my form is very relaxed though both are ran at the same pace. And from what ive observed, stiffness usually happens during fast interval runs. During easy runs, i find that after running easy for a long while, i still have the speed to maintain a fast pace for a long period of time. What do you think? Whats the reason why this happens all the time? It's not that kind of pain that lingers after workout. It's something that only happens during runs :/