It's called long distance SUL/UL solo cross-country fastpacking.
No rules, no sponsors, no fees, no designated routes, no help, no cheering crowd at the finish line.
Do what many of us do; find a really hard looking loop and go and try to do it. Try 30 miles in 24 hours. If that's not tough enough, try 50 miles in 24 hours. If that's not tough enough, try 120 miles in 24 hours. Throw in 25,000 feet of cumulative climbing for good measure. Not hard enough? Go barefoot. Still too cushy? Leave your shelter, sleeping bag, and jacket home. Hell, try it naked. I don't know of any "rules" for wilderness travel...Just don't let any rangers catch a glimpse of your naked erse going in; hence the 2AM start time without a light.
Just don't go dragging SAR into some ill-conceived epic or tell anyone I told you to do it.