Nine Data Dimensions for One Lane: When Vietnam's Swimming Data Sheet Is Still Empty

On my desk in Shanghai there is an Excel file called pool_empty.xlsx. It contains nothing but a header row: start position, reaction time, first 15 metres, stroke rate, distance per stroke, turn time, final 50 metres. Seven columns. Not a single number.

That file was born on a May evening, when I sat in the stands of an aquatics venue watching a final. The crowd screamed the winner's name. The scoreboard flashed a string of digits, then went dark three seconds later. No split sheet. No reaction time. Nothing to tell me what percentage of the winner's first-50 stroke rate survived at the 250-metre mark.

The race finished in front of me, and the only thing I carried home was memory. I keep that empty file to this day because it reminds me of one thing: most of the debate about Vietnamese swimming is happening on an empty spreadsheet, and people still draw conclusions with enormous confidence.

I was born in Vietnam, I work as a sports data analyst, and I currently report on swimming for the Chinese market. My job is to read a 50-metre lane and tell people what happened inside it. But my job has also taught me that most lanes in this region have never been recorded at all.

A race with no data still generates thousands of opinions. That is the real problem, not the result.

Since Nguyen Thi Anh Vien left the elite lane, Vietnamese swimming entered what I call the quiet transition. Fans still remember the gold medals at regional level. But the distance between a medal memory and a verifiable data system is a very different distance.

In 2026, at eighteen, I sat in a volunteer statistician's seat at a youth Asian championship in Shanghai. I built my own tracker with twenty variables per possession, purely to prove something the newspapers would not mention the next morning. My first article drew five thousand reads overnight, not because I wrote well, but because I was the only person holding a number.

Moving to swimming, I found the gap is far wider. At a football match, positional and event data is captured automatically, published openly, downloadable. At a regional swim meet, the only things usually released are the final time and the placing. Two data points. A 200-metre individual medley contains at least twenty separable measurement points.

Fans are not wrong to care only about who touched first. But someone in my trade is not allowed to stop there. When a swimmer is three seconds off a personal best, the right question is not "declining form" — it is where those three seconds live: reaction time, underwater phase, two turns, or the closing sprint.

Seven empty columns in my Excel file are not a minor inconvenience. They mark the boundary between a swimming nation governed by data and one governed by collective emotion. So I built myself a nine-dimension frame for reading a lane, even when the sheet is nothing but empty cells.

Dimension one: technique. A swim is not one continuous block. It is a sequence of start, underwater phase, swimming segments and turns. In the start, reaction-time gaps between elite swimmers are often a few hundredths of a second, but over 50 metres those hundredths are the entire ranking. In the underwater phase, world aquatics rules require the head to surface before the 15-metre mark; inside that zone, dolphin kicking produces far higher velocity than arm stroking. Whoever uses more underwater metres gets free advantage.

In the middle segment, two variables decide everything: stroke rate and distance per stroke. Their product is velocity. A swimmer can stroke very fast and still be slow, because the hand is not catching water effectively. Conversely, a swimmer with a slow rate who travels nearly two and a half metres per cycle is saving energy for the last 50. Without stroke data, every technical judgement is a guess.

At the turns, time is usually measured across five metres in and five metres out. This is where a strong swimmer can take half a second per turn, and across four turns in a 200-metre race that half second multiplies into two seconds. Two seconds is the gap between a medal and fifth place in most regional finals.

Dimension two: performance and data. A time standing alone is meaningless. It only means something against three reference frames: the world record, the all-time list, and the current-season ranking. The world record shows the ceiling of the sport. The all-time list shows where an athlete stands in history. The season ranking shows the present correlation of forces.

One technical note most people skip: a 50-metre pool and a 25-metre pool cannot be compared directly. A short course has more turns, therefore more push-offs from the wall, therefore greater velocity. A short-course record, however beautiful, cannot be placed beside a long-course mark without conversion. I have seen thousand-comment arguments run for days simply because nobody mentioned this detail.

On split structure, the most revealing thing is the shape of the halves. A swimmer who goes out slower and comes home faster is distributing endurance properly. A swimmer markedly faster in the first half will usually lose speed in the final 15 metres. But to know that, you need timing at every 50 metres. Without it, we fall back on feeling.

Dimension three: competition system and entry mechanism. For swimming, the four-year Olympic cycle is the most important time axis. The first year after a Games is a rebuilding year. The second is a foundation year. The third is when athletes begin appearing in continental finals. The fourth is when everything must ripen.

This means a regional result cannot be read the same way at every point in time. A regional gold won in a rebuilding year carries a very different predictive value from a regional gold won in the year before the Olympics. For Vietnamese swimming, the world federation's A-cut and B-cut standards are the narrowest gate, because they demand a specific time threshold regardless of how many regional rivals show up.

Dimension four: the global map of the discipline. At the dominant tier, the United States and Australia still split most swimming medals at recent Olympic Games. At the challenger tier, China has risen strongly in women's butterfly and distance events, Hungary has a tradition in individual medley, and Romania and Tunisia have produced Olympic champions in middle-distance events. In Southeast Asia, Singapore won an Olympic gold in the men's 100-metre butterfly at Rio 2026, a milestone for the whole region.

Vietnam currently sits in the potential tier. That tier has a characteristic: domestic results often do not correlate with international results, because there are no domestic rivals at the same level. An athlete can win a national title by two seconds and finish at the bottom of a continental field. That gap cannot be measured by feeling.

Dimension five: rules and anti-doping governance. This is the least discussed dimension in the region, and the one with the most severe consequences if ignored. Since high-tech swimsuits were banned from 2026, every record must be read in the technical context of the era in which it was set. A record from 2026 cannot sit beside a record from 2026 without acknowledging the equipment change.

Beyond that lies the out-of-competition testing system, athlete biological passports, and therapeutic use exemptions. For a developing swimming nation, the capacity to run out-of-competition testing locally is an infrastructure indicator as important as a regulation-size pool. When an athlete suddenly improves sharply within one season, the data analyst's reflex must be to question sample size and context before questioning medicine.

Dimension six: career trajectory and team system. The performance curve of a swimmer has a fairly characteristic shape. For women, the peak usually falls between eighteen and twenty-four, with some cases peaking earlier. For men, the peak usually comes later, commonly between twenty and twenty-six.

The puberty barrier is a real variable in this discipline, especially for young female swimmers with outstanding junior results. As the body changes, the ratio between strength and mass changes, and speed can fall even as training volume rises. This is why forecasting that a fifteen-year-old will win a continental title at twenty is a low-probability inference.

Alongside the age curve sits the training model. Centralised training groups, altitude camps, and a sports-science support staff are three pillars. Remove one, and the performance curve breaks at some point nobody records.

Dimension seven: risk profile. Risk in elite swimming splits into a few groups. Injury, typically shoulder impingement from the enormous accumulated volume of arm stroking over years. Overtraining, when training load rises faster than recovery capacity. Psychology, when an athlete walks into a first continental final in front of a full stand. And systemic risk, when funding or coaching resources are unstable across cycles.

The most worrying of the four is systemic, because it does not manifest as a specific injury. It manifests as a nineteen-year-old with real potential simply vanishing from entry lists, with nobody knowing why. In my Excel file, that is one more empty cell.

Dimension eight: public narrative and the expectation gap. In Southeast Asia, swimming is one of the sports that delivers the most medals for delegations at regional games. That creates a very particular expectation pressure: expectations at regional level are high, while the competitive threshold at continental and world level is entirely different.

The space between those two thresholds is where stories get distorted. A swimmer with multiple regional golds may still be below the Olympic qualifying standard. The media usually omits the second half. And when expectations are not met at a bigger stage, the reaction turns into personal criticism rather than a look at a data system that was never built to forecast accurately.

Dimension nine: industry ripple. A discipline does not exist in isolation. Upstream lies youth development, the learn-to-swim market, and the talent supply. Midstream are the athletes and the competition system. Downstream are media, sponsorship, equipment and derivative markets.

In Vietnam, the upstream has a characteristic that developed swimming nations do not have: demand for swimming instruction is tied directly to water safety, since child drowning rates have been a public health issue raised for many years. That means pool infrastructure here serves not only elite sport but a broader social goal. A good swimming data system in Vietnam, if it were built, would not serve only a few dozen elite athletes.

When the data volume in the technical dimension is empty, the only way forward is to change channels. I switch to physical data, to the competition calendar, to athlete psychology, to the turn-by-turn history of individuals across seasons. My job is not to wait for data to arrive, but to find which channel still carries a signal.

I once thought data was the answer. 2026 gave me a better question.

That year, as a student, I analysed a match in which the stronger side dominated possession and lost. I calculated that the losing side's expected goals were lower than the winner's, and concluded the result reflected reality rather than luck. My article was removed from a large forum for contradicting mainstream opinion. Since then I have understood one thing: data can stand against even the strongest media narratives, but a table of numbers with no clear provenance carries no weight at all.

A spreadsheet has no shirt colour, but I still hear the match through its columns. With swimming, I hear the lane through empty cells, in a different way.

This is the counter-intuitive point I want to state plainly. The absence of data in a swimming nation is not a neutral void. It is a choice, with winners and losers.

The winners are those who currently hold the power to interpret the story. When data does not exist, the default story is an emotional one: the hero, the sacrifice, the overcoming. Such stories travel far, and they cannot be falsified. You cannot refute an emotional story with numbers, because there are no numbers.

The losers are the athletes themselves. Without split data, they do not know which segment is weak. Without cross-meet comparison data, they cannot tell whether a good result is genuinely good or merely good because rivals were absent. Without season-long data, they cannot detect a declining trend until it is too late.

And there is another trap, the correlation trap: a swimmer changes coach, then posts a strong result, and people conclude the change was the cause. But if that swimmer also increased training volume, changed sleep and nutrition, and had a shoulder injury addressed, which variable produced the result? Without per-variable data, the answer is a belief wearing the costume of analysis.

Tactics are a hypothesis. Every hypothesis needs one Korean night to be tested by fire. In swimming, that night is a continental final falling on the exact day the athlete is at peak form.

The match ends, but the data keeps talking. In Vietnamese swimming, the race ends and the data goes completely silent. That is the story that truly has not been told.

What I want to see in the next cycle is not another regional gold medal. What I want to see is a public split sheet for a domestic swimming final, with reaction times and turn times for every swimmer. When that sheet exists, every argument about Vietnamese swimming will be lifted to another level, one where conclusions must answer to numbers.

These nine dimensions are not a formula for naming who is good. They are a frame for knowing what is missing. In a sport where the gap between a medal and fifth place is two seconds, knowing what you lack is worth more than knowing where you stand.