Despite the ease of the first heat, McLaughlin-Levrone isn't without competition. Femke Bol of the Netherlands is the reigning world champion. The two women are the only athletes to have ever posted a time below 51 seconds in the event.
McLaughlin-Levrone has the chance to defend her two gold medals from Tokyo during the track and field events at the 2024 Paris Olympics.
McLaughlin-Levrone won gold for the women's 400m hurdles and the women's 4x400m relay in the 2020 Olympics. She is expected to compete in both events in Paris and is a favorite to return to the top of the podium.
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McLaughlin-Levrone keeps pushing herself and the competition to new heights. At the Olympic Trials in Oregon in June, she set a new world record of 50.65 seconds in the women's 400m hurdles, her premiere event.
McLaughlin-Levrone is 24-year-old but will celebrate her birthday on Aug. 7 in the middle of competition in Paris.
Paris is her third Olympics. She's also competed in Rio in 2016, where she made her Olympic debut at the age of 17, the youngest U.S. Olympian in track and field since 1972. She lost in the semi-final around that year.
Sydney McLaughlin-Levrone is expected to compete in the women's 400m hurdles and the women's 4x400m relay, the events she and the United States are defending gold medalists in coming into Paris.
The women's 400m hurdles will take place from Aug. 4-8 at the Paris Olympics.
Sunday, Aug. 4 - The women's 400m hurdles first round takes place starting at 6:35 a.m. ET on Sunday, Aug. 4.
Monday, Aug. 5 - The women's 400m hurdles repechage round takes place starting at 4:50 a.m. ET on Monday, Aug. 5. Sydney would only race in this if she didn't place high enough from the first round.
Tuesday, Aug. 6 - The women's 400m hurdles semi-final takes place at 2:07 p.m. ET on Tuesday, Aug. 6.
Thursday, Aug. 8 - The women's 400m hurdles final will take place at 3:25 p.m. ET on Thursday, Aug. 8.
In the first found of the women's 400m hurdles, there will be six heats. The top three athletes in each heat will move onto the semifinals.
Athletes who do not qualify in the first round will have a chance to compete in a repechage round, which will feature four heats. The top athlete in each heat, and the two fastest athletes not already qualified, will qualify.
In the semifinals, there will be three heats. The top two in each heat but the fastest two who have not already qualified will advance.
The women's 4x400m relay events will take place Friday, Aug. 9 and Saturday, Aug. 10 in Paris.
Friday, Aug. 9 - The women's 4x400m relay first round takes place starting at 4:40 a.m. ET on Friday, Aug. 9.
Saturday, Aug. 10 - The women's 4x400m relay final will take place at 3:14 p.m. ET on Saturday, Aug. 10.
Four athletes from the same country run in a relay format with each racing 400 meters.
For the first 1.25 laps, each county must stay in their own lane, but can converge on the inside lane on the back stretch of the second lap.
Runners have 20 meters to pass the baton.
Athletes can be disqualified for dropping the baton, for passing the baton out of the designated exchange/takeover zone, or for corssing into another lane.
At most, 16 countries will qualify for the first round and then eight teams will compete in the finals.
