Vietnam's Blue Lanes After the Anh Vien Era: Rebuilding by the Hundredth of a Second

At the national swimming and diving championship finals held in Hanoi this past May, I sat in stand B with a lined notebook and a handheld stopwatch set to split every 50 meters. The starting area no longer permits recording devices, so all splits had to be recorded by hand and then cross-checked against the electronic board once the heat ended. An almost obsolete method in an age when every lane is scanned by tracking cameras at hundreds of frames per second. But that very hands-on approach gave me something the summary board never does: rhythm. In the men's 200m individual medley final, a swimmer I have been tracking for three seasons opened with a 26.4-second butterfly split, faster than some pure butterfly specialists. Onto the 50m backstroke, speed dropped to 30.1. The breaststroke leg - the fatal weakness of almost the entire Vietnamese swimming scene - took 33.8 seconds. The final freestyle dash: 29.9. Total: 2 minutes 00.2 seconds, breaking the old national record by exactly four hundredths. On the electronic board, that is a notable step forward. In my notebook, it is a warning written in blue ink. Because if you separate the four legs, the structure of this swim tells a completely different story: the athlete won with the butterfly leg and the freestyle leg, barely improved at all in breaststroke, and compensated with a final dash better than expected. On the international stage, a poor breaststroke leg is not compensated by a dash. It simply deducts points, and deducts them painfully. A national record can be built on a lucky final dash; a continental medal cannot. That is the starting point for the story I want to tell about Vietnam's blue lanes right now - the period I call the rebuilding after the Anh Vien era, measured in hundredths of a second. For nearly a decade, Vietnamese swimming lived in a very comfortable psychological state: there was one star large enough to carry almost all medal expectations, and the rest of the national team was allowed to swim in that shadow without too much scrutiny. Nguyen Thi Anh Vien, born in 2026, won dozens of SEA Games gold medals, competed at three consecutive Olympic Games, and set national records in almost every event of her specialty. She was an exceptional phenomenon, an athlete who arrived earlier than the training structure of an entire sporting nation. When a star arrives before the system, the system will believe it has already matured. That is precisely the first data trap I want to address. A sport can mismeasure itself by treating an outlier as the norm. During the peak of Anh Vien's career, Vietnam's swimming medal table at the SEA Games looked beautiful, but if you peel away her contribution from the total, what remains thins out visibly. I once rebuilt the medal tables of several SEA Games, separated Anh Vien's column into its own, and the remaining column left me silent. That was when I understood how deeply a single star can conceal a void. When Anh Vien left the elite competitive lane, that void was exposed. Not because Vietnam lost an athlete - that is the law of every sport - but because the whole system had never been built to run without her. The SEA Games that followed were a severe test, and the swimming medal table began to speak in a truer voice. I do not want to tell this story in a tragic tone. Tragedy is the easiest genre to write and the easiest to get wrong. I want to tell it through data, through splits, through competition structure, and through small anomalies most spectators never notice. Because in sport, what remains after a star is not regret - it is structure. And structure can be read. I have worked in sports data analysis for many years, but I came to swimming before football. In 2026, I started my career at a newsroom as a reporter covering swimming, back when everything was still recorded by hand at the poolside. That job taught me something that later became the backbone of how I write: in swimming, the distance between talent and result is not measured by inspiration, but by very specific numbers - splits, stroke rate, turn efficiency, breathing count. Years later, when I moved into deep data analysis, I carried that same discipline with me. Numbers do not lie, but people always find ways to lie with numbers. In swimming, the most common way is to pick the one number that talks, put it in the paper, and forget all the other numbers. So instead of asking whether Vietnamese swimming is strong or weak, I ask a different question: how is the technical structure of the swims changing, and is that change sustainable. To answer, I use a framework of three data layers. The first layer is the split map. Without a split breakdown, every remark is subjective. The second layer is swimming performance indices - turn efficiency, distance per stroke (DPS), stroke rate, number of breaths per length. The third layer is competition structure - the A and B cuts of regional and continental meets, the number of qualifying slots, and the role of relay events. These three layers, cross-checked against one another, usually point to the same sore spot. I always set my own rule: every number that goes into an article must be verified through at least three independent sources, and every chart must clearly state its statistical timestamp. At least three sources, no more no less, because this profession does not forgive anyone who relies on a single source. Now, let us go into the first sore spot, the one I call the collapse index. When analyzing the splits of a swim, I do not only look at speed. I calculate peak speed, then compare it with the speed in the final leg to find the rate of decline. If you take the fasted 50-meter speed as the numerator, the final collapse tells you whether the athlete has distributed energy rationally. At the world elite level, the decline rate between the fastest leg and the final leg in a 200-meter event usually falls between 4 and 7 percent, depending on the event. But most of the swims I recorded at domestic meets fall between 9 and 13 percent. That gap is not talent. Talent shows up in peak speed. That gap is distribution, tactics, base conditioning, and above all the ability to hold technique while tired - what the profession calls technique under duress. I have reviewed hundreds of swims and noticed a very repetitive pattern: domestic athletes swim the opening leg too fast relative to their base conditioning, then pay the price in the final leg. People think they win by leading. But in events of 200 meters and longer, leading is not winning. Leading is only a loan. The second sore spot is turn efficiency. Swimming is a sport decided by unseen moments - underwater, in the tumble turn, at the wall. A good turn can save three to five tenths of a second each time, and over long distances those turns multiply into real distance. I once measured a domestic athlete losing about 0.9 seconds per turn, while the regional standard is about 0.6. Twenty turns in a 1,500-meter event - that discrepancy adds up to a stretch of about six seconds, exactly the gap between a medal and absence. What is worth noting is that turning is pure technique. It does not demand gifted muscle as much as it demands repetition and training discipline. It is the kind of skill a sport with a good system can produce quickly and cheaply. The fact that we still lack it, therefore, is not a story about people - it is a story about process. The third sore spot is DPS, the distance covered per stroke. This is a metric rarely mentioned in our country yet it distinguishes the two schools of swimming most clearly. The group that chooses to increase stroke rate to swim faster - that is, faster strokes - will go farther in terms of instantaneous speed but tire quickly, and drop sharply at the end. The group that chooses to increase DPS will hold a longer rhythm, tire less, but demands near-perfect technique from start to finish. Most Vietnamese athletes swim in the first school. That is a reasonable choice given the existing training base, because increasing rate is easier to teach, easier to see results from quickly, and creates a feeling of speed on the electronic board in short events. But beyond a certain distance threshold, it exacts a price that keeps repeating. That is when I think of a line I hold dear: xG is not wrong, it is just that football is inherently irrational. After 2026, I learned to count the irrationality too. In swimming, I translate that line into: the technical model is not wrong, it is just that the human body is inherently irrational. After many years, I learned to measure the irrationality of the body too - which is the collapse speed in the final leg. The biggest sore spot, and the least discussed, is breaststroke. Among the four strokes, breaststroke is the most technically demanding, requires the most complex full-body coordination and also demands the greatest explosive power in the start and turn. In many regional countries, this is the event that gets abandoned because it is hard to teach and time-consuming. But breaststroke appears in almost all individual medley events - from 200 meters to 400 meters - and in mixed relay events. A swimming nation weak in breaststroke will hit a ceiling across a range of events: 200m IM, 400m IM, mixed relays. This is a structural debt, not a single weakness. I regard this as the sore spot with the largest ripple effect in the entire domestic swimming system. I do not say this based on feeling. I once built a multi-year tracking table, recording the breaststroke leg speed of each athlete against their own speed in other strokes, then against the regional standard, to find the discrepancy ratio. The numbers I got showed that the breaststroke leg is usually the leg that loses the most time in a medley swim, and most of the gap with the regional standard concentrates here. With distance freestyle events, the story is different. This is where I watch Nguyen Huy Hoang very closely. Huy Hoang was born in 2026, is a distance-specialist swimmer, and has achieved impressive results on the continental stage - a landmark boost for an entire generation of Vietnamese male swimming. He possesses something many domestic athletes do not: long-range conditioning and the ability to hold technique well over extended swims. But Huy Hoang also shows the limits of an individual when the sport around him is thin. One athlete alone cannot upgrade a system. And that is not the athlete's fault - it is structure. I want to pause here to make my view on structure clear, because this is where it is easily misunderstood. In swimming, there is a very large difference between short course and long course in technical terms. A 25-meter short course has more turns, meaning the weight of turn technique increases while the weight of base conditioning decreases. A 50-meter long course is the reverse. So if you read record tables as equal without distinguishing the two, you will compare things that cannot be compared. A good short-course result does not automatically convert into a good long-course result. This is the trap I see domestic sports managers still fall into. In particular, when regional, continental or Olympic events take place in a 50-meter pool, every short-course optimized result needs a conversion factor. Ignoring that factor is systematically lying to oneself. The relay story is the same. For many small swimming nations, the relay is not a technical goal but a medal-optimization goal. If you have one star strong enough and three athletes with an adequate base, you have four medal chances instead of one. This is a math with great appeal, but also a trap of laziness. It makes managers focus on building a few individuals to serve one team event, instead of building a broad training system. The result is that the bridges between relay teams weaken, because the bridge is depth. And what we lack is precisely depth. At regional meets, there is a system of A cuts and B cuts governing entry slots. For Olympic Games, an A cut is a performance level sufficient for an athlete to enter an event directly; in some cases, athletes meeting the B cut may take remaining slots depending on the number of entries. This is a system that benefits nations with deep internal competition. When internal competition is strong, an A cut is not just a target for one individual but a threshold for the whole sport to strive toward. Conversely, when you have only a few athletes reaching that threshold, all the pressure concentrates on a very small group. And a very small group is vulnerable to events. This is precisely where I want to bring up the concept of invisible pressure. There is a pressure no one sees, yet every team fears it. I named it: Binh Duong pressing. I know the name is attached to another sport, but its mechanism can apply to swimming. In swimming, invisible pressure is the pressure of teammates and internal squad pressure. When an athlete knows there are two people behind ready to overtake them in the domestic qualifiers, the way they swim the final leg will differ. When there is no one behind, they swim with an unconscious safety. That state of unconscious safety shows most clearly in the final sprint - where a data model can read a gap of just 1 to 2 percent in speed, but on the international stage it decides the ranking. I have tracked many swims over many years to reach this conclusion, based on cross-checking split indices with the squad structure in each period. Athletes in groups with a dense internal field tend to have a more stable final sprint. This does not lie in any single training session; it lies in structure. Now, I want to tell a story that once changed my writing dramatically. In 2026, when the pandemic brought almost the entire sporting world to a halt, international swimming meets were also suspended. When meets returned under spectator-free conditions, I treated this as an unintended giant laboratory. Continuously tracking swimming meets held under empty stands, I noticed one thing: performance indices in the final sprint changed, and they changed unevenly across groups. This is an observation with great power, because it shows that what seems to depend only on muscle has a significant psychological-social component. Without spectators, some athletes lose a source of energy they never realized they were using. Others are liberated, because the stadium pressure has vanished. When the stadium is empty, every model collapses. I rebuilt from the half-burnt data. In the case of swimming, that half-burnt data was the spectator-free meets. I learned to read them, and from then on I understood that no model can replace context. That was also when I became a writer hunting for anomalies, not describing matches as surface phenomena. In swimming too, I always ask: what does the data prove contrary to the crowd's view? That is the question that shapes every analysis I write from those years onward. From that observation, I draw three conclusions contrary to intuition about domestic swimming. First, Vietnam's gap with the region is not in the butterfly leg, but in the breaststroke leg and in turn ability. What catches the viewer's eye - those powerful butterfly or freestyle legs at the start - is precisely the part that creates the least distance. Second, when we over-optimize for regional medals, we inadvertently optimize for contests with a large weight on short-term sprints, and weaken long-term structures - especially distance conditioning and turn technique. This is a form of goal distortion with systemic character. Third, sometimes what we need is not a better athlete, but more good average athletes. A group of athletes all at a decent level will raise the internal training standard, and the internal standard is what creates real performance thresholds, not statements made to the media. I am aware these conclusions can be misunderstood as criticism. But I do not write to criticize. I write to distinguish between two kinds of signals: signals that show the fierce competition of a system that is evolving, and signals that show the loneliness of a few individuals swimming against the current. I once treated models as scripture. Now it is only a compass - but without it, we are lost. In the case of Vietnamese swimming, that compass is pointing in two very clear directions: training depth, and foundational technique. It is also worth mentioning one factor I have watched very closely in recent years: the structure of the national team across the congress cycle. In swimming, the career of an elite athlete usually lasts about ten years. That means each Olympic cycle - once every four years - allows a sport to replace only about three generations of athletes. If one generation is short, the structure exposes a gap for years. With Anh Vien, her golden period coincided with a long stretch without corresponding generational replacement in the age groups below. That is not her fault - it is the problem of a training system not organized by cycle. Swimming is a sport with a very long training cycle. An elite athlete does not come from one year of training; they come from ten years of structured development. So when you build a national team, you must look at the adolescent cohort and ensure each generation has enough manpower to produce a few elite-level athletes within the next ten years. This is where I want to talk about the concept of a talent map - something I once applied to football when evaluating youth tournaments, and which can perfectly be applied to swimming. A good talent map shows the age groups, the localities, the training bases, and most importantly the vertical flow - how athletes move from one generation up to the one above. When a talent map lacks verticality, you see only isolated stars. When it has verticality, you see an entire current. I once used this concept to analyze a tournament and was called too domineering by some colleagues when I dared to predict results very early. But that is the price of being a data writer: if you do not dare to stand on the side that can be wrong, you have nothing to defend. Early predictions are the only evidence that you truly believe in your data. In swimming, I also want to apply that method. I want to publish a prediction about the structure of Vietnamese swimming in the coming cycle, knowing it can be wrong. And I am ready to pay that price. My prediction is as follows. If Vietnamese swimming continues to prioritize regional medals without simultaneously upgrading breaststroke technique and turn technique in the youth cohort over the next two to three years, the gap with the continental standard will widen further, even if the regional medal count does not fall. I call this the beautiful medals, deep gap scenario. On the other hand, if breaststroke and turn technique are brought into the youth training system, and if there are enough athletes at the B cut level to create internal competition, then within one to two cycles, we will see swims with a lower final decline rate, and the gap with the A cut will begin to narrow across many events rather than just one or two individuals. I call this the rebuilding scenario. I do not say which scenario will happen. I only say that the data allows us to observe progress signals, and those signals will appear in very small places: turn speed, final-leg decline rate, the breaststroke leg in medley swims, and the number of athletes meeting the B cut or above. Reputation is only a name. What remains is always how you read the contest. In swimming too: the name of a star will fade, but how a sport reads itself through numbers will remain. And in the end, it is precisely that reading that decides whether we can rebuild. One question remains that I have not fully answered, and I leave it here as an open point: is Vietnamese swimming truly lacking talent, or is it lacking a structure good enough for talent to develop to the international competitive threshold? If the answer is the second part, then the work ahead is not to find more stars, but to rebuild the foundation. That is slow work, unglamorous, and almost never makes news. But it is precisely that work that decides whether we can break the ceiling. I will keep recording splits by hand at the poolside. And when my notebook shows the final-leg decline rate of the youth generations beginning to fall, that will be when I know the rebuilding has truly begun - before any medal table confirms it. For now, I am still waiting for the next-cycle signal.