RIOT AND LAG

This has been a recurring problem recently for the past few weeks. I'm just casually playing league then right before teamfights break out i massive ping spikes and freezes and i know what your thinking " maybe your just unlucky " or " maybe your setting " ive tried it all. It really ruins the gaming experience of league that i want to love but cant because of this random lag. It does the exact same thing in 1v1's as well i walk near my opponent and i get more lag then i had before. If there is a logical explanation for this, please put it down below.