Swimming's Ledger and the Blockchain: From an Empty Column to the Shadow of the Betting Feed

Last month a run sheet from a swim meet landed in my hands. The left column held fifty-two lines of script for the people in the seats; the right column held the same beats retimed for the stream. Walking the seam between the two columns, my eye caught an empty cell — a 50-metre split. The time was there, the name was there, the lane number was there; only the split was missing. In swimming everything is measured in time, yet the data that breaks time down is the thing that vanishes. For seventeen years I have kept the ledger, and these empty cells are what trouble me most. The run sheet split in two, and I followed the seam — and on the far side of the seam was a blank cell.

For the same reason, when a certain analysis file reached me last week with the same sentence on every page — "insufficient information, cannot assess" — I was not surprised. I am used to it. Living with empty cells is our daily work in swimming. But the question has now moved somewhere else. Who will fill these empty cells? And in answer, everyone has suddenly begun to pronounce one word — blockchain. Swimming records, the chain of custody for doping samples, athletes' biometric data, tickets, even betting feeds — the name of blockchain is coming up everywhere. The question is therefore not simple. The question is whether blockchain will truly write the ledger of the water, or lay another layer over the empty cell.

The sport where data is the only language

Swimming is among humanity's oldest sports, yet modern swimming is entirely a sport of numbers. Touch pads, timing systems built by Omega or Speedo, a resolution of 0.01 seconds — these are now indispensable. When a race ends, what remains is not just a time but a row of splits: the mark at 15 metres, at 25 metres, the turn time, the stroke rate, the distance per stroke. More than two hundred member federations submit their registered times to the World Aquatics database, and it is from there that records receive recognition. The 46.40-second world record in the men's 100-metre freestyle at last year's Paris Olympics would be impossible without fraction-of-a-second precision.

But who keeps this data, where, and who verifies it? The answer remains foggy. National federations submit times, international bodies verify them, sometimes a correction is made, sometimes a controversy arises. Touch-pad error, manual backup timing, the different conditions of heats versus finals — suspicion returns every cycle. That place of suspicion is blockchain's entry point. In an immutable ledger, if every time, every split, every correction were recorded with a date, no one could reach back and alter a record. The idea is elegant. The question is how well the idea holds on swimming's ground.

It is worth simplifying what a blockchain actually is, because the word is often misused in sport. A blockchain is a ledger in which each new entry is mathematically bound to the previous one. If someone tries to alter an old entry, the whole chain breaks, and it is caught immediately. There are two kinds — a public chain that anyone can inspect, and a permissioned or private chain that only approved institutions may write to. Sport generally uses the second, because federations and sponsors do not want every piece of data open to all. In that single description lies blockchain's greatest limitation for swimming: where the ledger is not open to all, accountability is not held by all either.

Core analysis: testing blockchain across six layers

The integrity of records. Swimming's greatest asset is the record, and the record's greatest enemy is correction. Once a time is recognised, if it is later changed, fans, journalists and even the athlete are confused. An immutable ledger can solve much of this. But there is a condition that usually gets buried in the discussion. The blockchain does not improve the accuracy of the timing system that produces the data. If the touch pad gives a wrong time, the blockchain will make that error permanent; it will not fix it. The blockchain does not prove truth, it provides the immutability of truth. The distinction is not small. If a wrong time is correctable today, tomorrow it will no longer be correctable — only provable that a correction was once made. Sometimes correctability matters more than correction.

The chain of custody in anti-doping. From sample collection to the lab, from the lab to the result, every step of the journey needs a chain of evidence. WADA's ADAMS system does this, but a centralised database means single control. On a blockchain, if every handover of a sample is time-stamped, the room to swap a sample or tamper with a result shrinks. This matters in swimming because medals are decided by the smallest margins, and once doubt is born it circles for years. If a disputed sample lives only in one institution's database, the question lingers; if multiple parties can see the same ledger, the question slowly fades. Here the blockchain's role is not judge but notary — it does not decide, it merely records who did what and when.

Ownership of athletes' biometric data. The modern swimmer is no longer only a swimmer but a living sensor. Heart rate, stroke rate, lactate, sleep, fatigue — this data is valuable to coaches, federations, sponsors, even investors. The question is, who owns it? A blockchain-based consent ledger can give the athlete a framework to control the use of their data — a transparent account of who uses what data, for how long, and for what purpose. But in swimming the problem is already deep. In many countries the athlete does not even know where their data goes, or at what price. Before understanding ownership, a simpler right is needed — the right to know who is looking at your data. Blockchain can be the instrument of that right, but only when the athlete themselves holds a key to the chain.

Fan tokens. Platforms such as Socios and Chiliz are already selling tokens to fans in football and other sports, in exchange for voting rights or special privileges. In swimming or Olympic-style sports this model is still at the margin. Because swimming's fan culture is not club-based but event-based, and the event returns only a few times a year or every four years. Where fan tokens want long-term engagement, swimming is a sport of fragmented emotion. If a supporter cannot vote on anything the day after their favourite swimmer's final, the token is only a souvenir, not effective engagement. This is why the football model does not sit directly on swimming, and those who try to place it there usually forget the sport's own rhythm.

Tickets and the secondary market. At big events, ticket forgery, scalping, resale — these are old problems. NFT tickets can control price and ownership in the secondary market. For swimming this is attractive exactly where an Olympic final's tickets sell out in seconds. But one thing must be watched: the fan who follows swimming all year never gets a final's ticket, while the one who comes only to the big event does. Ticket technology does not reduce this inequality; it sometimes increases it, because the NFT market fixes a price and creates an opportunity for profit, not for fandom.

The betting feed. Here lies the greatest shadow. Companies such as Sportradar or Genius Sports sell live data to betting firms. A split, a turn time, a disqualification — all of it moves into the betting market within seconds. Blockchain can make this feed more transparent, faster, more verifiable. But transparency is not morality. The faster the data, the faster the bet, the faster the profit — and the larger part of that profit does not go into the swimmer's pocket. Data born of a swimmer's physical labour, yet its beneficiary is someone else. This is the central unease of swimming's data economy, and blockchain does not soothe it, sometimes sharpens it.

The river's ledger: where the empty cell is truly empty

Looking at my own country's swimming, this discussion takes another shape. In Bangladesh a modern 50-metre outdoor complex means essentially one, and it carries the weight of age. For four decades the country has attended the Olympics through universality places, but no one has reached a semifinal on merit. Much of what passes for national records was born in services-division competitions dominated by soldiers and labourers. The question here is not blockchain; the question is — if there is not even data worth recording, what will the blockchain record? For a federation that does not preserve the splits of every heat, an immutable ledger is a strange, almost comic object — an empty box with an extremely sturdy lock.

Yet the water of this country carries a whole heritage. In 2026 Brojen Das crossed the English Channel to become the subcontinent's first swimmer to do so. Then Abdul Malek, then Mosharraf Hossain, then a long silence of thirty-seven years, and finally the 2026 relay. That heritage, trained in Dhaka's Buriganga, today exists in no immutable ledger, in no document, in no database. My river file survives only in memory, not on paper. If blockchain's greatest promise is not to forget, its work here is most urgent — and also most difficult, because to write one must first have data, and to gather data one must first have the will.

I can never merge the deck's data and the river's data in one pen. The deck's ledger holds splits; the river's ledger holds a name, a year, a current. In 2026, anchoring a broadcast across thirty-two days in two languages, I learned that to translate information one must verify every word, check every term's meaning with two coaches. Recording data is much the same — the machine merely writes; a human must grasp the meaning. Blockchain is a new language, and like any new language its grammar must be learned, or it will produce words without meaning.

And the other face of this data is grim. Every year in Bangladesh many children drown, and even that number is not fully accounted for. I do not bring this figure into every swimming piece, because a number, passed around, goes numb. But one thing should be remembered: a country that cannot save its children from water does not treat swimming as a luxury but as infrastructure. Blockchain will not save lives here; yet a genuine ledger would at least let us know where the risk is and where the progress is. One name, one district, one programme — these three do more work than a number.

The contrarian view: an empty cell is not filled by technology

While everyone looks toward blockchain, an uncomfortable thing must be said. Technology cannot fill a gap created by the absence of data. For an institution with no splits on hand, blockchain offers only an empty box with nothing to put in it. Swimming's problem is not technological; it is a culture of record-keeping. If a national federation does not even register times, no blockchain can create those times. The causation is inverted: we mistake a lack of information for a lack of technology, and then buy technology as consolation.

The second point is more uncomfortable. The most profitable use of swimming's data is in the betting feed, not in the swimmer's biometric data. To an economy that bets on every second of a race, an immutable ledger means a more reliable feed, faster transactions. Who gets blockchain's benefit — the swimmer, or the betting economy sitting behind them? This question is usually left unanswered, because asking it puts a hand on the model. When sports data is treated purely as an asset, the swimmer becomes a kind of asset themselves, and their story of the water finds no place.

There is a third, more innocent error — trusting the two columns equally. I could arrange every swimming story as blockchain versus river, official versus marginal, ledger versus memory. But a swimmer's story cannot always be bound into a conflict. Sometimes it is better to follow a single column all the way down, because sometimes one teenager's swim is enough on its own, without turning them into an illustration of a theory. In 2026 in Tokyo, when the mixed 4x100 medley relay debuted, I explained before anyone else how two men and two women are ordered, and why a coach chooses a particular order to protect the weakest leg. The explanation protected the swimmer, not the technology. The empty room of 2026 taught me that the camera was then the audience, and for that camera I wrote pauses, not applause. The empty room taught me that a river still announces the game.

The takeaway: who owns the ledger

The wrong question is whether blockchain will come to swimming. The right question is who will own the ledger. If the future's immutable ledger is written only for betting firms and sponsors, the swimmer will be a single line of entry, and their river story will be nowhere. But if that ledger also keeps the name of Bangladesh's Buriganga, if the split of a teenager in lane eight and the drowning toll of a district are written side by side in the same ledger, then technology will, at least once, repay its debt. In the next cycle I will watch whose name is written on the new canvas, and whose name is left lying in the empty cell.

I keep the details others drop; that is how I host the past. From my years of watching matches I can say that a ledger is never neutral — who writes it decides who is left out. The empty column is therefore not merely a cell; it is a decision. The only question is whether we are making that decision consciously.