Oh, the Olympic 10K Marathon Swim at the 2024 Paris Olympics is going to be quite an extraordinarily interesting race to watch.

Imagine the speed of the world’s fastest marathon swimmers flying down the Seine when they are swimming in the direction of the river flow.

But now imagine the struggle when they have to comeback against the current.

Whoa. That is going to be one incredibly strategic race. What are the swimmers and their coaches planning to do?

Decision-making during the Olympic 10K Marathon Swim

• Do you pick up the speed going with the current? Especially if you swim around the turn buoy first or among the first few swimmers? Imagine being 15th in the pack of 33 swimmers in the men’s race – or 20th in the pack of 27 swimmers in the women’s race. As the swimmer bunch up and slow down around the first few turn buoys, the lead swimmers are going to get a huge jump on the rest of the trailing pack.
• Or do you pick up the speed going against the current? Especially if you have the make up lost time vis-a-vis the top swimmers in the lead pack? But is that extra effort going to wear on you? Is it going to take something away from your closing speed?
• What about swimming between the two turn buoys at the tight ends of the course? If the Seine current is very fast, how much do you adjust your direction so you hit the next turn buoy just right? Is it best to take the turns on the inside of a large pack – or the outside?
• Do you draft on the outside of a competitor going with the current – or the inside? What about going against the current?
• Do you slow down – or speed up – as you come into the fixed feeding pontoon? How do you and your coach time it just right so you can grab your feeds at precisely the right moment? If the current is flowing fast and you miss your feed, what are your alternatives?
• What happens if flotsam or jetsam hits a swimmer – or a swimmer swims into floating debris on the river? While the first swimmers in the lead pack may be able to see debris in the water and avert a head-on collision during the race, will the second- and third-tier swimmers in the lead and training pack be able to see and avoid that same debris?
• Against the current, do you swim nearer the middle of the Seine – or closer to the shore banks?

Who really knows?

What coaches and what athletes are going to compute and predict all these different possibilities?

There are so many strategic plans to make before the swim – and many more tactical decisions to make during the actual Olympic 10K Marathon Swim.

How are the television and online announcers going to call the river race? How much information will they be able to relay to the global audiences – in real time? While the flow of the river will certainly be fast enough for the swimmers to feel, will the river currents be visible to the television and online viewers?

Normal Flow of the Seine

The normal current of the Seine is between 100 to 150 cubic meters per second during the summer.

From the end of June to the middle of July, the current has been running nearly five times faster – occasionally nearly up to seven times faster than normal (670 cubic meters per second).

That is an incredible difference – and something that all experienced open water swimmers can appreciate.

Considering the rectangle course of the Olympic 10K Marathon Swim in the Seine, it is inevitable that the swimmers will be racing almost incomprehensibly fast with the current – and struggling against the current.

How Fast Is Fast?

At 500 cubic meters per second, the officials and media boats will be moving in the river at 12 km per hour.

12 kilometers per hour – or a speed of 1 kilometer every 5 minutes – or 30 seconds every 100 meters. Add the swimmers’ normal fast pace to that current, and the swimmers will be traveling faster than 30 seconds per 100 meters…along the fast legs of the course.

If the current starts to flow at a rate of 670 cubic m/s, the swimmers could potentially be swimming the enter length of 595 meters along the fast length of the rectangular course in less than 2 minutes.

2 minutes to swim nearly 600 meters.

That speed can really change things.

The current of 500 cubic m/s was too fast for the Paris Olympic Games organizers to hold their opening ceremony rehearsal for three weeks. The organizers were just too worried about maintaining boat speed and maneuverability.

Official and Media Boats

There are always many official boats and media boats on the Olympic 10K Marathon Swim course. There are also turn judges who sit on boats near the turn buoys.

If the current is potentially flowing above 500 cubic m/s, how do the boat pilots manage holding these boats, either still in place or slow during the race? Will personal watercraft be used? If a boat loses control, how do they avoid the swimmers.

How Fast Is the Seine Now?

Watch here – and then imagine the world’s fastest open water swimmers racing with that current – and against.

Analyses

Gerry Rodrigues, coach and founder of Tower 26, has spent decades racing in all kinds of conditions. He talks about the possible currents – both positive and negative – and its impact on the athletes, “Generally, swimmers with greater power can overcome negative currents with relatively greater ease, thus able to put time into their competitors.

Conversely, they won’t gain anything when in the positive flow, in fact, the slower athletes can stay within closer proximity and even gain with positive flow.

Depending on the duration, not distance, that an athlete spends in the negative flow, will likely determine the outcome of this race.

The strategy would be for more powerful swimmers to really press the negative flow legs, and then recover during the positive flow legs. Stated differently, athletes who have done LOTS of resistance training, i.e., swimming with extra weight, drag devices, dryland power building, etc. should be served well for this race. The slender, less powerful, more endurance type athlete would likely be punished more.

Cadence rates will play a role during the negative flow.

It’s going to come down to simple math…time in positive flow versus time in negative flow. That should dictate strategy.”

Steven Munatones says, “I think the men and women’s races will be slightly different if the current is flowing faster than 500 cubic m/s. On the men’s side, the lead pack will include many of the absolutely fastest and fittest men in the world for any distance over 400 meters. In that case, I would recommend that the fastest and fittest swimmers race for that first buoy (assuming they will be swimming against the current on the first le) in order to try to be among the leaders flying with the current on the backstretch.

Why?

If the current is flowing fast, they could cover 600 meters in under 2 minutes. At those speeds, even with a 10-second differential, there could theoretically be up to 50 meters of difference between the leaders and swimmers in positions #10-15, at least. I know that this differential might even out on the way back up against the current, but in these races the lead pack usually just maintains and extends their lead for a few reasons: they are generally the faster swimmers, but also the lead pack has fewer swimmers. As such, there is less physicality in the thinner lead pack. Also, very importantly, they are in the lead and can dictate the race. Their competitors have to respond to them.

Also, swimming into and out from the feeding pontoons is much easier within a smaller pack.

Also, the race officials tend to focus their attention on the larger packs where there is more physicality. Within those larger packs, all things being considered, the swimmers are given more warnings by whistle and occasionally more infractions, usually yellow cards – which further impacts – and limits – their performance.

Also, within the smaller packs among the leaders, the buoy turns are significantly easier and faster with much less probability of getting hit or elbowed or pulled back. Within the larger packs, swimmers either have to swing very wide or sometimes they get caught squeezed in the middle on the inside. All these can cause valuable time and effort.

Plus, trying to catch up to swimmers who swim under 14:40 for 1500 meters when there are no waves does not seem highly likely – because the course in the Seine will be clearly laid out and the banks are straight so navigational IQ is not needed like in a rough water ocean swim.

On the women’s side, the favorites are all experienced and strong open water veterans – all within a fairly narrow range of speeds from 200 meters to 1500 meters – and they know each other so well – that I do not think they will let a few fast pool swimmers surprise them.

That being said, someone like Moesha Johnson, the fast Australian with a 15:55.75 speed in the 1500 meters could be pushed by American Katie Grimes with her 1:57.19 200m and 15:44.89 1500m speed. If they break away with a fast downstream leg, they could gain a tactical advantage over Leonie Beck, Ana Marcela Cunha, Chelsea Gubecka, Mariah Denigan and all the other veterans who are savvy and strong enough to force the women’s lead pack to be quite large and extremely physical. With a lot of physicality present, the most experienced swimmers usually end up on the podium.”

Male Olympic 10 km Marathon Swimmers

• Kyle Lee, Australia
• Nick Sloman, Australia
• Felix Auboeck, Austria
• Jan Hercog, Austria
• Guilherme Costa, Brazil
• Martin Straka, Czech Republic
• David Andres Farinango Berru, Ecuador
• Carlos Garach Benito, Spain
• Logan Fontaine, France
• Marc-Antoine Olivier, France
• Hector Pardoe, Great Britain
• Tobias Patrick Robinson, Great Britain
• Oliver Klemet, Germany
• Florian Wellbrock, Germany
• Athanasios Charalampos Kynigakis, Greece
• David Betlehem, Hungary
• Kristóf Rasovszky, Hungary
• Daniel Wiffen, Ireland
• Matan Roditi, Israel
• Domenico Acerenza, Italy
• Gregorio Paltrinieri, Italy
• Taishin Minamide, Japan
• Woomin Kim, South Korea
• Paulo Strehlke Delgado, Mexico
• Phillip Seidler, Namibia
• Henrik Christiansen, Norway
• Piotr Wozniak, Poland
• Victor Johansson, Sweden
• Ahmed Jaouadi, Tunisia
• Emir Batur Albayrak, Turkey
• Kuzey Tuncelli, Turkey
• David Johnston, USA
• Ivan Puskovitch, USA

Female Olympic 10 km Marathon Swimmers

• Chelsea Gubecka, Australia
• Moesha Johnson, Australia
• Ana Marcela Cunha, Brazil
• Viviane Jungblut, Brazil
• Emma Finlin, Canada
• Xin Xin, China
• Maria de Valdes Alvarez, Spain
• Angela Martinez Guillen, Spain
• Oceane Cassignol, France
• Caroline Laure Jouisse, France
• Leah Phoebe Crisp, Great Britain
• Leonie Beck, Germany
• Leonie Martens, Germany
• Bettina Fabian, Hungary
• Giulia Gabbrielleschi, Italy
• Ginevra Taddeucci, Italy
• Airi Ebina, Japan
• Martha Sandoval Ayala, Mexico
• Lisa Pou, Monaco
• Sharon van Rouwendaal, Netherlands
• Maria Alejandra Bramont-Arias, Peru
• Angelica Andre, Portugal
• Mariah Denigan, USA
• Katie Grimes, USA

© 2024 Daily News of Open Water Swimming

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