At the Rio de Janeiro Games, 10 world records have been broken in swimming and athletics with just two days of action remaining.
The Straits Times looks at some marks that have been shattered.
1. Men's 400m
New record: Wayde van Niekerk in 43.03 seconds on Aug 14, 2016
Old record: Michael Johnson in 43.18sec on Aug 26, 1999
Prior to these Olympics, the men's 400m world record had been broken just twice since the 1968 Mexico City Games, when American Lee Evans posted 43.86sec. Evan's time would have been good enough to win gold at Munich 1972, Montreal 1976, Moscow 1980, Los Angeles 1984, Seoul 1988, Athens 2004, and London 2012.
It took almost 20 years before American Butch Reynolds shaved 0.57sec off it, and another 11 years for Johnson to take it down by another 0.11sec.
Johnson's 43.18sec effort was widely regarded as an almost unbreakable record. The closest anyone came to that mark was compatriot Jeremy Wariner (43.45sec) in 2007 before van Niekerk took to the track on Aug 14.
From lane eight, the South African crossed the line in 43.03sec - bettering Johnson's record by 0.15sec. No man had ever won the 400m from the outside lane.
2. Women's 10,000m
New record: Almaz Ayana in 29min 17.45sec on Aug 12, 2016 (awaiting ratification)
Old record: Wang Junxia in 29:31.78 on Sept 8, 1993
Ethiopia's Ayana did not just break Wang's record that stood for 23 years, she obliterated it by taking more than 14 seconds off.
Wang's mark had been questionable since the Chinese runner reportedly admitted to doping this year, forcing Ayana to address questions on whether she was on drugs.
Ayana rejected all accusations after what was the fastest-ever women's 10,000m race.
No woman had gone under 30 minutes in the last seven years. But the first four finishers all boasted sub-30 times. The top 13 finishers all clocked personal best times.
3. Men's 100m breaststroke
New record: Adam Peaty in 57.13sec on Aug 7, 2016
Old record: Peaty in 57.55sec on Aug 6, 2016
Great Britain's Peaty broke his own mark two times in as many days in Rio - in the heats and final.
He first became the world record holder in April 2015, when he clocked 57.92sec. The 21-year-old remains the only swimmer to go under 58 seconds in this event.
He finished 1.56sec ahead of silver medallist Cameron van der Burgh - the largest margin of victory in the history of the two-lap race.
Van der Burgh was the world record holder before Peaty. The South African's 58.46sec effort in July 2012 stood for over two years and nine months.
4. Women's 400m individual medley
New record: Katinka Hosszu in 4min 26.36sec on Aug 6, 2016
Old record: Ye Shiwen in 4:28.43 on July 28, 2012
When China's Ye won gold in the 400m individual medley at the 2012 London Games, she stunned the world. Over the last 50m she was quicker than American Ryan Lochte, who had won the men's event in the second-fastest time in history.
Ye went 1.02sec under Australian Stephanie Rice's world record - set en route to winning gold at the 2008 Beijing Games.
In Rio, Hungarian Hosszu went 0.77 per cent faster than Ye in 2012, taking 2.07sec off the world mark.
To put the progression of this event's world record in perspective, China's Chen Yan (4:34.79) bettered East Germany's Petra Schneider (4:36.10) mark by 1.31sec in 1997. Schneider's mark stood for over 15 years and 2 months.
5. Women's 800m freestyle
New record: Katie Ledecky in 8:04.79 on Aug 12, 2016
Old record: Ledecky in 8:06.68 on Jan 17, 2016
American Ledecky was without peer in the final, and arguably, in this event's history.
She was 11.38sec - or almost half a pool-length - ahead of silver medallist Carlin Jazz of Great Britain. Her time of 8:04.79 was also 9.31sec lower than the anyone in history, with Great Britain's Rebecca Adlington posting 8:14.10 to become the world record holder in 2008.
Before Adlington's effort, the mark was held by American Janet Evans for 19 years.
Now, Ledecky owns the 13 fastest times ever in the 800m free. Since clocking 8:13.86 to win gold at the 2012 London Games, she has broken this event's world record five times.
