I wanted to take a moment and warn everybody against the societal pressure to perform extreme feats (like ultramarathons or excessive weight lifting) to be considered "fit." Fitness is personal and should not be defined by comparisons to others, but rather by consistency and working toward one's goals. As I've often said, the Greek ideal was moderation. (The Greek saying is, "Nothing in excess.") This means adhering to an exercise program that's the best possible one for you. The appropriate regimen is something only you can figure out for yourself.
Just some thoughts.
Have a wonderful day!