Apparently there is a difference between the “world record” and “world’s best.” In any case, the “world’s best” title belongs to the former British long-distance runner, Paula Radcliffe who set it in a race where she was paced by men.
That title is still over two minutes faster than any women’s marathon in history. Her speed is simply unbeatable and no one other woman has come close. The only one who can top that title is Radcliff herself.
Oscar Robertson The Offender
The NBA had a crazy year from 1961-62. The defense playing practically disappeared and the number of possessions each team had per game sky-rocketed. Beyond Wilt Chamberlain, almost no one gained anything more from this offensive boom. Unless you were Oscar Robertson. His triple-double average was buoyed by the fact that the team points per game average that year (118.8) was the highest in the league's history.
Of course, we will never see that little emphasis placed on defense ever again, so the probability of a player being able to maintain that kind of output for an entire season is non-existent.
The Lakers 33 Wins Remains Unbeaten 40 Years Later
In 1971 the LA Lakers achieved the unthinkable when they won 33 games in a row. Anything is possible but it's going to take a majorly powerful team to break that record. The 73 win Warriors couldn't even do it.
In 2008, the Houston Rockets challenged that record but last after 22 games. In the time the Lakers had their hot streak, they beat their opponents by an average for 17 points a game.
Grete Waitz The History Maker
Grete Waitz achieved the unimaginable when she did not only become the first woman in history to run a marathon in under two and a half hours, but she also won 9 New York City Marathons between 1978 and 1988. That is more than any other runner in history.
How did she do it? Sheer super-human abilities apparently.
Rocky Marciano Knock Out Champ
Knockouts are common in the heavyweight class, far more than in the lower weight classes. So for a boxer to not only go 49-0 but to also get 43 knockouts in the process sounds like an impossibility.
The famous Klitschko brothers couldn't even rack up those kinds of wins. Floyd Mayweather may have a higher knock out rate but he's in a lower weight class and intentionally avoids both delivering and taking big hits, so we can't compare.