Last weekend saw the rare occurrence of world-level triathlon events taking place concurrently. On the Saturday, Chengdu hosted a World Cup race. The following day, athletes took on another World Cup event in Brasilia.
The double header meant that there were smaller fields than usual although both events had broadly similar numbers. More importantly, the back-to-back World Cups offered a chance to compare how World Cups can unfold in different ways.
Of course, different courses will affect races in different ways. On that note, Brasilia was a hillier course than Chengdu. The different athletes starting will also bring different qualities to the table. As a result, it would be unlikely for any two races to look the same, even if elite triathlons frequently follow a similar set of patterns.
The focus of the comparisons in this article will be on the swim and run in Chengdu in Brasilia. In Chengdu, the athletes took on a two lap 1500m swim and a four lap 10km run. In Brasilia, the athletes had a single lap in the 1500m while the run consisted of three laps.
The differences were likely less pronounced in the swim. In both races, wetsuits were not permitted so athletes were racing under the same conditions. The difference in laps also would have had a fairly small effect on the field.
Rather than focusing on individuals, we will look at the field as a whole. More specifically, we will look at how the times in the swim and run were distributed across the entire field.
If the below graphs look the same, an argument could be made that World Cup racing is more similar than not, even with the differences in course and start list. By contrast, if the graphs look different, we will be able to more clearly visualise how different athletes can bring about different outcomes at World Cup events.
Swim
Men
The men’s swim in Chengdu saw Márk Dévay and Dylan McCullough push into an early lead. By the end of the 1500m, the pair had earned a lead of 18 seconds over the next quickest man, the race winner Tim Hellwig.
The 18 second gap can be seen in the above graph. Dévay and McCullough emerge at the front and then the density of athletes drops. It then picks up with the arrival of Hellwig and the chasers.
Notably, the peak density of athletes exited the water around the 30 second mark. This put a large gap on the heels of the two leaders, making it harder for them to stay clear on the bike.
The density then dropped rapidly at the 40 second mark, only to pick up again as a second large group formed. The second pack would later merge with the main chase group during the bike. Meanwhile, Dévay and McCullough were caught on the first lap of the bike.
As such, the swim stretched the men’s field in Chengdu, but it did not ultimately break the field apart.
Interestingly, the men’s swim in Brasilia looked completely different to that of Chengdu.
Rather than having a small two-man breakaway at the front of the race, a large group fought for control. In Chengdu, the opening density of athletes was under 0.005. In Brasilia, it was around 0.01 higher, a sizeable increase, as a more established front pack came together.
The peak density also came a lot earlier in Chengdu. The concentration of athletes peaked at the 15 second mark and from there only really dropped. There was a second bounce in density around the 55 second mark, although compared to the main pack this was insignificant in size.
When comparing Chengdu and Brasilia, it would be easy to think that the swim in the former yielded a small breakaway group on the bike. After all, the pack had broken up whereas in Brasilia a throng of athletes arrived in T1 together. Yet the opposite was true.
The field came back together on the bike in Chengdu but clear packs formed in Brasilia. By the end of the bike, the front pack in Chengdu was almost three times larger than in Brasilia. The extra hills on the course in Brazil may have helped towards this outcome.
Nevertheless, we can see that the men’s swims were quite different and that the subsequent outcomes on the bike did not fully conform to standard expectations.
Women
The women’s swim in Chengdu had a similar dynamic to the men’s albeit with one clear difference. Rather than two athletes darting away at the front, the women’s swim was dominated by Bianca Seregni. She swam 23 seconds faster than the next best athlete.
In a way, the women’s swim distribution then looks rather like the men’s race in Brasilia. If you take out Seregni, the peak density would have been fairly close to the leader and then dropped considerably.
As it happened, Seregni was soon caught on the bike (instead of trying to take on the race solo). A large front pack then came together over the course of the bike which makes sense given how clustered the field had been in the water.
If we turn to the women’s swim in Brasilia, we see something completely different.
Again, the swim saw a solo leader set the pace; this time it was Vittoria Lopes that impressed. Behind the leader, though, the density of athletes was all over the place.
You can see three clear spikes in the concentration of athletes at the 20, 45 and 70 second marks. Essentially, every 25 seconds a new group formed. Moreover, the three groups were broadly comparable in size.
The tireless work of Miriam Casillas Garcia in the second pack (the spike at 45 seconds) helped that group catch the front pack. Thereafter, the front of the field was made up by a pack of a similar size to the lead group in Chengdu.
Thus, while the women’s swims looked rather different, the outcomes later on in the race were much more similar.
Run
Men
The above run time distributions for the men’s races in Chengdu and Brasilia show how the race concluded in different ways.
In Chengdu, a large pack stayed together throughout and any of at least six men had a realistic shot of winning the gold. The top-6 were separated by a matter of seconds (with the silver and bronze medallists matching one another’s times to the second). As a result, the greatest density of athletes on the run was actually at the front of the race.
Brasilia was a little different. Miguel Hidalgo, Antonio Serrat Seoane and Charles Paquet broke clear on the first lap of the run. Then, on the final lap, Hidalgo broke clear to win by over 20 seconds.
The men’s graph therefore starts at a lower density as Hidalgo was alone. While the density in Chengdu continuously decreases, in Brasilia it rises and then more or less stabilises until the 200 second mark.
The two graphs therefore capture the difference between pack running and a sprint finish against a much more broken up field.
Women
In the women’s race in Chengdu, Seregni ran away to victory with the fastest split of the day by 30 seconds. With the biggest winning margin of the four victors at the weekend, her performance saw the women’s race in Chengdu start with the smallest density on the run.
A very spread out top-5 meant that it took quite some time for the density to rise. It only really grew at the 90 second mark, indicating just how much the majority of the field had fallen behind the winner.
In Brasilia, the story was different. Alice Betto won the race ahead of Katie Zaferes by a smaller margin. From there, the density steadily rose. By the 90 second point (where the women’s density only began to rise in Chengdu), the density of athletes had already peaked in Brasilia.
The front of the field, then, was much more tightly-bunched in Brasilia.
Further behind, Chengdu saw three clear peaks in density while Brasilia only saw a second peak.
Overall, the examples of Chengdu and Brasilia show how different Olympic distance racing can look at the same level. Different athletes and different courses play their part but it is interesting to see how radically opposed the profiles of Chengdu and Brasilia looked at times.
The main takeaway from this is that no two elite triathlons really look the same. Many may have similarities, but each race has a certain unique quality to it.
