Winning an Olympic gold medal is quite an accomplishment regardless of what event it is in. Winning 7 gold medals of the course of 8 days is an achievement that the world had never seen up until this point and Mark Spitz was completely dominant in the Munich swimming pools that particular Olympics.
The year was 1972
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you weren't allowed to play sports without a mustache in the early 70's
In 1968, Mark kind of upset the world with his arrogance as he claimed he was "definitely going to win 6 medals." He only won two, which would be the best day ever for us mere mortals but Mark was extremely disappointed. The media and most Olympic fans actually applauded his inability to back up his bold claims but apparently failing to deliver had an effect on Spitz because he began training even more vigorously and turned up in 1972 with something to prove... this time, he kept his mouth shut and let his swimming do the talking.
Mark entered 7 events in the 1972 Olympics. He won gold in all 7 events and also set a new world record in each and every one of them. Not all of them were singles events of course but lucky for Spitz, the rest of his teammates were also quite accomplished in the ol' swimming hole. Many of the individual events saw USA taking the silver medal as well as Mark's gold.
Mark truly held himself to a different standard than the rest of us: Nervous about entering the 100-meter freestyle (his weakest stroke) he told a reporter " If I swim six and win six, I'll be a hero. If I swim seven and win six, I'll be a failure."
Official tribute video from the Olympic channel
Watching this video seems really strange by today's standards. Many of the opening dives seem almost amateurish the way that their legs drag upon entry - some even look almost like belly flops. You can also see that almost no one wears swim caps and I didn't notice a single person wearing goggles. There were plenty of mustaches though.
I might be wrong about this but i think mustaches are now banned because it gives competitors an unfair advantage.
It should come as no surprise but he is regarded as one of the greatest athletes of all time. Mark Spitz' record of winning 7 medals in one Olympic Games stood for 36 years before it was broken by Michael Phelps in 2008 at the Beijing games. Phelps is a superhuman though, and no one should feel bad about having their record broken by someone that has a career 23 gold medals.
I wasn't alive when it happened, but according to my friends who were, Mark's face was everywhere after this Olympics. He was admired by everyone. Consequently, Mark was the first swimmer to make a ton of money in sponsorship deals after his Olympic performance.
When asked about whether or not he is upset about his record being broken by Michael Phelps, he replied "Phelps is the greatest Olympic athlete ever... how can anyone be upset about that?" Whether or not that is genuine sentiment, only Mark knows, but it was a nice public gesture regardless.