The Data Gap at Istora Senayan: Why Elite Badminton Remains the Least Quantified Sport

In June 2026, at Istora Senayan, I sat in the sixth row behind the technical area, my left hand holding a stopwatch and my right hand holding a notebook with a worn spine. It was the Indonesia Open, one of four Super 1000 events on the BWF World Tour, and also the tournament that closed the career of Hendra Setiawan — a man who had walked alongside Mohammad Ahsan through nearly two decades, three world championship titles and an Olympic gold medal. My camera was set at a 45-degree angle, just enough to catch his feet in the third game. In that match I timed 41 rallies, an average length of 7.2 seconds per rally and an average gap of 11 seconds between them. Total shuttle-in-play time came to under 25 minutes, while the match ran more than an hour. When I sent those notes to an editor in Jakarta, he replied: “Nobody publishes figures like this, what would we check them against?” He was right. A 7.2-second rally does not live on the electronic scoreboard; it lives on the green matting, and the sound of the racket striking the shuttle rings once and dissolves into the roar of the stands. Badminton has one of the most transparent competitive frameworks of any speed sport. The BWF World Tour is clearly tiered: Super 1000 includes major events such as the Indonesia Open, the All England, the Malaysia Open and the China Open; below that sit Super 750, Super 500, Super 300 and the International Challenge circuit. The ranking system works on a 52-week cycle, points are published after every round, and Olympic qualification is determined by a race ranking that runs for nearly a year. As an institution, it is a machine with almost no grey areas. In terms of match data, the story flips entirely. What the BWF releases to the public amounts to scores, rankings, schedules and a few scattered serving statistics. There is no rally length. No distance covered. No shuttle speed at each contact point. No count of direction changes, split steps or reaction time before a smash. Tennis has Hawk-Eye and ATP Insights fed straight into television broadcasts; athletics has 100-metre split times; swimming has 50-metre splits. Badminton, whose shuttle travels faster than the ball in almost any other sport, leaves audiences to absorb nearly all of it by feel. Consider one anchor point. In 2026, Indian doubles player Satwiksairaj Rankireddy set a Guinness record with a smash measured at 565 km/h. That is the figure most repeated by media whenever badminton's raw power is discussed. But the racket leaves the shuttle at that speed, and the shuttle cannot hold it: air drag decelerates it so sharply that by the time it reaches the opponent, the real velocity is many times lower. A beautiful number on a banner tells only half the story on court. Put another way, the only metric most people have ever heard about badminton is the one most likely to mislead them. At Istora Senayan the problem is more complicated. The arena is famous for the roar of Indonesian crowds, yet few people talk about how the airflow inside the hall and Jakarta's humidity can bend a shuttle's flight path by several centimetres on high clears. The world's leading players must adjust their placement and power after just a few contacts in the warm-up. That entire process of adaptation — which decides matches more reliably than any powerful smash — exists in no statistical table. I once filmed an Indonesian men's player standing at the back line, raising a hand to measure the wind direction, then saying exactly one sentence to his coach: “The shuttle is heavy today.” Nobody recorded that sentence except us. The Paris 2026 Olympics offer another example. An Se-young of South Korea won women's singles; Viktor Axelsen of Denmark successfully defended his men's singles gold. In women's singles, Gregoria Mariska Tunjung of Indonesia took bronze — Indonesia's first Olympic medal in women's singles — in a draw where no bronze-medal match was played, because Carolina Marín of Spain had to leave the court with a knee injury in the semi-final. An Olympic medal decided by a knee, not by a scoreline. The scoreboard records the result; it cannot record the cause. Also after Paris 2026, An Se-young publicly criticised the Korean badminton federation's management and medical care system, saying her injury had been mishandled during the most important phase of her career. There is no dataset against which to check that story, yet it points to a gap larger than any statistical one: a gap of accountability. When an athlete has to confront the institution of her own sport to say that her body was damaged, rankings and points stop being the meaningful terms of the argument. On the Indonesian side, the PBSI national training centre in Cipayung remains the place that produces most of the country's elite players, from Hendra Setiawan's generation to Anthony Sinisuka Ginting. This centralised model creates obvious advantages in intensity and sparring quality, but it also puts enormous pressure on a small group of athletes and a small group of specialists. Whenever the centre faces turnover in staff or budget, the effect lands directly on competitive results within the following eighteen months. I once cut a short film about conditioning sessions there and realised their training programmes are excellent, yet almost no data is stored systematically enough to compare across generations of players. Vietnam sits in a different position. Nguyễn Thùy Linh — Vietnam's top women's singles player, who has been ranked inside the world's top 30 — and Lê Đức Phát are the two most heavily invested prospects, but their resources come mainly from personal effort and a handful of sponsors, not from a data system or a dedicated analysis team. Watching them compete on the World Tour, what I see most clearly sits in logistics: an opponent analyst, a travelling sports doctor, a videographer to break down footage after the match. None of that shows up on a results board, yet all of it decides results. There is a paradox worth stating plainly: fans are demanding more data, but more data will not automatically produce more understanding. Badminton runs on micro-variables — the timing of the split step, the angle of the wrist on a drop shot, the distance between a player's position and the predicted landing point. Machines can measure those things, but once measured, someone has to know how to read them. If the BWF opened its positional tracking archive, the first thing to appear on social media would be smash-speed leaderboards, not analyses of movement structure. Transparency does not automatically generate depth. Beyond that, the badminton industry has limited economic incentive to open up. Detailed tracking data is the property of organisers and broadcast partners; national federations treat internal fitness and injury data as competitive secrets. No body exists to standardise it, and no single tournament is large enough to force the whole system onto a common standard. Tennis needed decades and an extremely powerful commercial coalition to reach the statistics infrastructure it has today. Badminton, with a more fragmented tournament structure, will move even more slowly. Yet the “lack of data” argument itself deserves caution. Across six years filming backstage, I have learned that most of what decides a match is not in the metrics but in the people standing outside the beautiful frame. A line judge decides a point at a moment the naked eye cannot follow. A shuttle handler places the shuttle in the right spot at the right rhythm so a player can serve within two seconds. A stringer picks a tension accurate to half a kilo and knows how tightly that player likes it on a humid afternoon. No statistical system quantifies those decisions, and none needs to in order to show they matter. Before the first rally, someone bent down. Before there were spectators, someone painted a line. And there are footprints that only appear when you stand still long enough to look — something a camera placed at the right angle can do better than any spreadsheet. A match ends when the clock stops, but the story only begins there. When the Indonesia Open closes and the roar of Istora fades, what remains on the results page is a string of scores. What remains in our footage archive is thousands of minutes of unrecognised footwork: a split step half a beat slower in the third game, a turning motion a coach asked to be corrected for two months, a shrug from Hendra Setiawan as he left the court one last time. If badminton one day has an open data standard, we may know exactly how many kilometres a player covered in a semi-final. But will we know why he was still running in the seventieth minute of the third game, when the title had already slipped out of reach? That is a question no scoreboard can answer on anyone's behalf, and perhaps it is also why I still carry a notebook next to the camera.