2024 Olympics Race Data Breakdown: Women’s 50 Free

The French governing body for swimming (Fédération Française de Natation) recently released a data analysis booklet of each event raced at the Paris Olympics. In this data-packed guide, information including swimmers’ 25m splits, time spent underwater, total stroke count, and more are laid out in a table with a breakdown of each finalist’s information. Over the next few days, I’ll be choosing some of my favorite races from the Olympics and analyzing the data behind the world’s fastest swimmers.

This data gold mine, all in French, has four distinct sections: Laps (splits), Parties Nagees (Parts of the race swum), Parties Non Nagees (Parts of the race not swum, including the start, underwater, and finish), and Mouvements (total strokes and such).

LOOKING BACK

The women’s 50 freestyle was raced on the final day of competition, and with the men’s 1500 freestyle and both medley relays also being in the same session, it was certainly not one that we’ll forget soon. Sarah Sjostrom won her second gold medal of the meet, Meg Harris swam a sub-24 for the first time in her career to take home silver, and Zhang Yufei earned her fourth (out of an eventual five) bronze. Seven out of the eight swimmers in this heat were seeded within the top eight coming into the final except for Slovenia’s Neza Klancar, who was originally entered at 23rd with a seed time of 24.70. The women finished in the following order:

1. Sarah Sjostrom (Sweden) – 23.71
2. Meg Harris (Australia) – 23.97
3. Zhang Yufei (China) – 24.20
4. Gretchen Walsh (United States) – 24.21
5. Katarzyna Wasick (Poland) – 24.33
6. Neza Klancar (Slovenia) – 24.35
7. Wu Qingfeng (China) – 24.37
8. Shayna Jack (Australia) – 24.39

LAPS (SPLITS)

To the 25m mark:

1. Sjostrom/Walsh – 10.98
2. .
3. Harris/Zhang/Wasick – 11.20
4. .
5. .
6. Jack – 11.14
7. Klancar – 11.28
8. Wu – 11.32

Largely thanks to her stellar underwaters, Gretchen Walsh tied the world record holder halfway down the pool, with both swimmers taking less than 11 seconds to reach the middle. What’s odd is that five of these swimmers tied with another to the middle of the pool (which I haven’t come close to seeing in any other race this far) demonstrating how close the women’s 50 free was amongst the third-through-eighth swimmers.

PARTIES NAGEES (PARTS OF THE RACE SWUM)

This section provides the swimmers’ times from 15m to 25m, as well as their times from 25m-45m, accounting for everything except the start and the finish. The following ranking is their total time from the 15m mark to the 45m mark.

1. Sjostrom – 15.28
2. Harris – 15.35
3. Zhang – 15.59
4. Klancar – 15.63
5. Wasick – 15.64
6. Wu – 15.65
7. Jack – 15.75
8. Walsh – 15.83

Sarah Sjostrom‘s consistent speed largely helped her dominate this race. Her consistency in the middle 30 meters as well as her other elements (see more in the next section) continued to show how she became the world record holder. In an opposite way, Gretchen Walsh‘s middle 30m is not her strong suit in the 50, and this race’s was one of the things that kept her off the podium. More than half a second off of Sjostrom’s middle 30m time, Walsh used the other 20m to place herself fourth, only a hundredth of a second behind Zhang Yufei. Aside from Walsh, this order is very similar to the finishing order, which makes sense given that this metric relies on a swimmer’s stroke speed.

PARTIES NON NAGEES (PARTS OF THE RACE NOT SWUM)

This section highlights the starts and finishes of the race, including reaction times, time spent underwater, distance covered underwater, time to hit the 15m mark, closing 5m time, and distance from last stroke into the wall. The following ranking is the total time spent to the 15m mark and in the last 5m going into the wall.

1. Walsh – 8.38
2. Sjostrom – 8.43
3. Zhang – 8.61
4. Harris – 8.62
5. Jack – 8.64
6. Wasick – 8.69
7. Klancar/Wu – 8.72
8. .

Sjostrom had the fastest reaction time in the field, with a 0.61 second time, and Gretchen Walsh had the slowest with a 0.75. But Walsh’s reaction time was quickly made up by her underwaters, as she was easily the first swimmer to the 15m mark. Walsh was the only person to hit the standard in under six seconds (5.88), with the next closest being Sarah Sjostrom with an even six. Meg Harris was the slowest to the initial mark, with 6.27 seconds. Neza Klancar and Walsh had the longest underwaters, with 15.28 and 15.47 respectively. (While this mark is beyond the legal limit, the measurement– “sortie de coulée” is not from where their head pops up, but where their breakout is). Katarzyna Wasick spent the least time underwater, beginning her breakout after only 9.47m, a full six meters before Gretchen Walsh.

Meg Harris had the fastest 5m-closing time, and also the shortest “Approache mur” (wall approach- distance from last stroke to wall) distance, at 2.35s and 0.28m. Wasick had the longest glide into the wall, with a 1.31m distance– over a meter more than Harris. Although she had the fastest underwater of the field, Walsh’s back-end speed was slightly slower than the rest of the field, and she took the longest time to touch after 5m (albeit marginally, with a time of 2.50).

MOUVEMENTS (STROKE)

This final section modeled the total strokes that each swimmer took during the race, and the following ranking shows from most-strokes to least.

1. Wasick – 41
2. Jack/Harris – 40
3. .
4. Wu/Zhang – 39
5. .
6. Sjostrom – 38
7. Klancar – 33
8. Walsh – 32

An odd fact about this section is seen in the ties, with both Australian swimmers and both Chinese swimmers taking the same amount of strokes. Harris and Jack have different coaches, as do Wu and Zhang, so this metric looks to be purely coincidental. The amount of strokes appears to be directly correlated with the time spent underwater at the start of the race, with Walsh and Klancar having by far the fewest amount of strokes and Wasick taking the most. A slight surprise comes from Zhang Yufei who, despite spending 13.01 meters underwater (the third most in the field), took nearly as many strokes as Wasick, Jack, and Wu, who all swam less than 10.75m underwater.

For the full breakdown: see the booklet here.