2024 Olympics Race Data Breakdown: Women’s 100 Back

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 Nagées (Parts of the race swum), Parties Non Nagées (Parts of the race not swum, including the start, underwaters, and finish), and Mouvements (total strokes and such).

LOOKING BACK

The rivalry between Kaylee McKeown and Regan Smith was temporarily settled at this year’s Olympic Games, with McKeown defending her title from 2021, winning in a time of 57.33. Smith, who finished second in the event with a time of 57.66, is still the world record holder, with a best time of 57.13 seconds. Katharine Berkoff earned herself a spot on the podium by breaking the 58 second barrier and swimming a 57.98 to take home bronze. This race was one of the only ones that we’ve seen in Olympic history where only four swimmers were represented, with Australia, the United States, Canada, and France sending both of their swimmers to the final. The swimmers finished as follows:

1. Kaylee McKeown, Australia – 57.33
2. Regan Smith, United States – 57.66
3. Katharine Berkoff, United States – 57.98
4. Kylie Masse, Canada – 58.29
5. Iona Anderson, Australia – 58.98
6. Ingrid Wilm, Canada – 59.25
7. Emma Terebo, France – 59.40
8. Beryl Gastaldello, France – 59.80

LAPS (SPLITS)

Opening 50:

1. Smith/Masse – 28.02
2. .
3. Berkoff – 28.05
4. McKeown – 28.08
5. Anderson – 28.47
6. Wilm – 28.69
7. Terebo.- 28.79
8. Gastaldello – 28.80

Closing 50:

1. McKeown – 29.25
2. Smith – 29.64
3. Berkoff – 29.93
4. Masse – 30.27
5. Anderson – 30.51
6. Wilm – 30.56
7. Terebo – 30.61
8. Gastaldello – 31.00

For most of these rankings, there seems to be two distinct groups of swimmers, with McKeown, Smith, Berkoff, and Masse (swimmers that finished 1-4) being the first and Anderson, Wilm, Terebo, and Gastaldello (finished 5-8) being the second. The first group all finished within a second of each other (McKeown at 57.33, Masse at 58.29), as did the second (Anderson at 58.98, Gastaldello at 59.80). In the first group, the swimmers all flipped at virtually the same time, within 0.06 seconds of each other, but McKeown pulled away in the second 50 to win the race. The times from the second 50 matched the final race order exactly.

Smith’s opening 50 was right around where it was when she broke the world record (27.94), but she didn’t have the same back-half speed that we saw from her at US Olympic Trials in June.

PARTIES NAGÉES (PARTS OF THE RACE SWUM)

This section provides the swimmers’ times from 15m to 45m, as well as their times from 65m-95m, accounting for everything except the start, turn, and the finish. The following ranking is their total time spent “swimming.”

1. McKeown – 36.81
2. Smith – 37.20
3. Anderson – 37.34
4. Masse – 37.36
5. Berkoff – 37.39
6. Terebo – 37.44
7. Wilm – 37.73
8. Gastaldello – 38.44

Generally, this part of the analysis tends to reflect the order of the swimmers, without many surprises. The swimmers that combine for the best “swimming” and “non-swimming” times are the ones who win the races. When Kaylee McKeown‘s time was around 0.40 seconds ahead of Regan Smith for 60 meters of the race, it’s difficult for Smith’s underwaters and turns to make up for the deficit.

PARTIES NON NAGÉES (PARTS OF THE RACE NOT SWUM)

This section highlights the start, turn, and finish 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 from the start to 15m, 45-65m, and 95m to the wall (measured in seconds).

1. Smith – 20.46
2. McKeown – 20.52
3. Berkoff – 20.59
4. Masse – 20.93
5. Gastaldello – 21.36
6. Wilm – 21.52
7. Anderson – 21.64
8. Terebo – 21.96

McKeown, Smith, and Berkoff were all right in the mix during both the swimming portion and the auxiliary parts of the race. The segment where they seemed to separate themselves from the rest of the field, earning their spots on the podium, was in their starts, turns, and underwaters. The difference between first and eighth in both this portion and the “swimming” portion was roughly the same, but the distribution was much more segmented in the “non-swimming” part. The podium finishers clumped together with Masse not far behind them, seemingly being the difference that separated them from the rest of the field.

Total distance swam underwater (measured in meters from the start of the breakout):

1. Smith – 30.2
2. Berkoff – 28.9
3. Wilm – 27.9
4. McKeown – 27.7
5. Gastaldello – 26.8
6. Masse – 26.7
7. Anderson – 25.8
8. Terebo – 24.0

Again, we see the American influence on this segment of the analysis. Smith and Berkoff both had the best underwaters in the field, thanks largely in part to their success in SCY swimming.

Distance and time from last stroke into the wall:

1. Anderson – 0.21 meters, 0.13 seconds
2. Wilm – 0.28 meters, 0.17 seconds
3. Terebo – 0.54 meters, 0.33 seconds
4. Smith – 0.56 meters, 0.34 seconds
5. McKeown – 0.64 meters, 0.38 seconds
6. Gastaldello – 0.75 meters, 0.46 seconds
7. Masse – 0.83 meters, 0.51 seconds
8. Berkoff – 1.27 meters, 0.80 seconds

Each swimmer has a different way that they like to finish their backstroke race, some choosing to get much closer to the wall and others choosing to resubmerge to finish their race. Ingrid Wilm and Iona Anderson both came very close to the wall before they took their last strokes, whereas Katharine Berkoff was further out when she took her last stroke, submerging 1.27 meters off of the wall and finishing her race with a powerful kick. Smith and McKeown seemed to prefer the middle option, closer to the wall than Berkoff but with more of a glide than Anderson and Wilm.

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. Berkoff/Anderson – 77
2. .
3. Smith/Terebo/Gastaldello – 76
4. .
5. .
6. Masse – 75
7. McKeown – 70
8. Wilm – 66

Distance per stroke (most to least):

1. Wilm – 1.092 meters per stroke
2. McKeown – 1.033 meters per stroke
3. Terebo – 1.000 meters per stroke
4. Gastaldello – 0.963 meters per stroke
5. Masse – 0.977 meters per stroke
6. Anderson – 0.964 meters per stroke
7. Berkoff – 0.923 meters per stroke
8. Smith – 0.918 meters per stroke

Smith and Berkoff’s race plan of a higher stroke rate/fewer meters per stroke in juxtaposition with McKeown’s lower stroke rate/higher meters per stroke again shows that there are multiple ways to reach the podium. Ingrid Wilm, with an impressively low 66 strokes, was sandwiched (in both lane and rank) between Anderson and Terebo, who both took at least 10 strokes more.

Unfortunately, no part of this data accounts for the kick rate, likely because it’s much more difficult to get an accurate reading on the exact amount of each swimmer’s kick. Just from looking at the race footage, much more white water is being generated by Smith and Berkoff than Terebo and Wilm.

For the previous data breakdowns, see the following articles:

• Women’s 50 Free
• Men’s 100 Breast
• Women’s 200 IM
• Men’s 100 Free

For the full breakdown: see the booklet here.