Assuming you meant "ever" and not "every", "take" in this case refers to length of time - how much time is spent doing something. The time used is "as long as this took me", the length of time it took the speaking to do something. The "nothing" and the "ever" combined function similar to "never", it is saying it has never happened before. And who is taking this time? "Any human". So, it's a bit of exaggeration saying that what the speaking did was the longest lasting activity that any human has ever done, basically emphasizing how long it was.

The verb 'to take' can be used to indicate the amount of time an action requires. For instance, it takes me an hour to prepare dinner. The real action is this sentence is preparing dinner, but the verb 'to take' indicates how much time has passed, or will have passed, in order to complete that action. So in your example, whatever action the word 'this' describes has taken a very large amount of time to complete. It would be much clearer if the sentence featured a direct object to the word 'this'. Written that way: Nothing has ever taken any human as long as this marathon took me.

First, the sentence should read "Nothing has ever taken any human as long as this has taken me." ¨Take¨ here refers to the duration of time. "as long" meaning "as much time" or "as long a time" The sentence means that the writer thinks that something they have done has been so slow to complete, i.e. has taken so much time, that no-one else has ever done anything so slowly or over such a long period of time. Obviously its an exaggeration, but that´s okay.