The Load Curve and the Forgotten Injuries of Vietnamese Swimming

In 2026, at the national youth swimming finals in Da Nang, I sat in the fourth row of the stands, holding a yellowed notebook. Not to record results. I was counting the number of times a fifteen-year-old female athlete pressed her hand against the pool edge after finishing a lap. Over four races that day, she pressed her hand eleven times. In two of those moments, her right shoulder rose noticeably higher than the left as she reached for a towel. Four months later, I received word that she had to stop training for six weeks due to shoulder tendinitis. No one on the coaching staff remembered that afternoon in Da Nang. No one cross-referenced anything. And that is precisely the problem with Vietnamese swimming. At Lach Tray, I learned to read injuries from the very first numbers. But when I shifted to watching swim lanes, I recognized a crucial difference: football is loud, while swimming is silent. A footballer with a hamstring injury will have hundreds of cameras pointed at him. A swimmer with shoulder tendon degeneration will quietly skip an afternoon session, rub his shoulder, and slip back into the water the next morning. That silence is fertile ground for accumulated mistakes. This article is not meant to criticize anyone. It aims to set against each other the data tables I have recorded over six years, from training centers in Hai Phong, from national youth competitions, and from four cases where I tracked athletes before and after their collapse. I want to tell the story of a sport where the athlete's body is pushed to its limit while the load-monitoring system is almost nonexistent. Vietnamese swimming has a paradox at the very heart of its pools. In our country, this discipline is tied to childhood, to summer classes, to survival skills. Every year, thousands of children are taught to swim. But the gap from "can swim" to "competitive swimmer" is a chasm without a bridge. Children learn to swim casually, then a few with talent are selected into accelerated classes. There, they enter a training regimen in which no one precisely measures the physical load they must bear each day. From 2026, when I began systematic tracking, I recorded a notable rate within a group of about sixty athletes across two talent pipelines in the north and central regions. Between 2026 and 2026, I documented 94 injuries requiring intervention (meaning rest of three days or more). Of these, 41 were in the shoulder area, 22 in the lower back, 17 in the knee, and 14 in the elbow and wrist. The common thread: more than two-thirds occurred during the load-increase phase in the first six to ten weeks of the preparatory cycle. That number does not mean swimming is dangerous. It means something else: the load curve breaks at exactly the point the body has not yet adapted. The body is a closed system, but data is the key that opens it. And that key, here, is being left in the drawer. In football, people have reached the point of debating GPS vests, sprint-load indices, high-speed running distance. In swimming, we still measure by... hours. "In the morning I swim three hours, in the afternoon two and a half." That is the most classic and most meaningless unit in sports physiology. Three hours for a breaststroke swimmer is entirely different from three hours for a freestyle swimmer. Three hours at a heart rate of 140 differs from three hours at 180. Three hours with 80% resting intervals of twenty seconds differs from three hours of continuous swimming. When I proposed measuring swimming volume in meters and by intensity zones for a youth training center, the response I received was: "Why count meters when swimming, what matters is the feel for the water." That answer is half right. Feel for the water is irreplaceable in swimming technique. But feel for the water does not tell you whether the shoulder tendon is accumulating micro-damage in week four or week seven. I once tracked a seventeen-year-old male butterfly swimmer across a seven-month cycle, cross-referencing the coach's training log with the athlete's subjective feel. In the first two months, the coach's estimated volume rose from 42 to 58 kilometers per week, but the athlete's personal log only recorded sessions as "heavy" or "light". He had no concept of the number. By week seven, he began to feel that "the water is heavier". That phrase, I learned, is the earliest sign of shoulder overload. Three weeks later, the diagnosis confirmed shoulder tendinitis. Had we had data, we would have seen the break point in week five, not week ten. Every fall has a graph, and every graph has a breaking point. The problem is we look at that graph after the break, not before. There is a physiological principle any sports medicine practitioner knows by heart but rarely applies correctly in Vietnamese swimming: the rule that load increase should not exceed 10% of volume per week during the base phase. This principle has been validated in running and many other endurance sports. But in swimming, it is often broken for a very human reason: the competition calendar. The national youth championships usually fall in June and July. To prepare, centers must push volume up in March and April, exactly the phase when athletes need to build foundations. The pressure to peak at a fixed date drives coaches to increase load faster than tendons and ligaments can adapt. Tendons do not adapt by the week. Tendons adapt by the month. That is the technical reason why youth swimming has such a high rate of shoulder injury. I often ask coaches one question: "If you increase volume by 20% this week, do you know how your swimmer's shoulder will respond next week?" The common answer is: "If he hurts, we reduce." This is a reaction-based prevention model, not a prediction-based one. And in a reaction model, you are always one step behind. By the time an athlete reports pain, the micro-damage is already at stage two or three. Kane 2026 was not a curse, but a simple subtraction. I use this line for football, but it applies intact to swimming. An athlete's breakdown after a run of results is the outcome of a simple arithmetic of accumulated volume against recovery capacity. There is no fate here. What struck me most is a paradox in how youth swimming is coached in Vietnam. We teach technique meticulously. A single stroke or kick can be corrected hundreds of times. But what gets corrected is technique in the water, not the body on land. In other words, we swim well but maintain the body poorly. A machine assembled precisely without a maintenance schedule will fail at exactly its weakest point. For a swimmer, that point is almost always the shoulder. A swimmer's shoulder endures a mechanical paradox. The humeral head rotates within the socket with an enormous range of motion, while four muscle groups around the shoulder must hold it stable. Each freestyle stroke repeats roughly 1,200 to 1,500 times in a long session. For an athlete training twice daily, six days a week, the weekly stroke count can exceed 15,000. Set beside a tennis or volleyball player, this number is even higher in terms of monotonous repetition. Monotony is the hidden enemy, because the body gets no chance to vary its loading pattern. For this reason, countries with developed swimming systems usually apply three parallel measures: first, rotating muscle groups by diversifying land-based training; second, dividing volume by intensity zones to avoid continuous repetition at high intensity; third, monitoring fatigue signs through subjective perception indices and periodic mechanical screening. These three measures require no expensive technology. They require something cheaper but harder: the discipline of record-keeping. I once proposed that a center adopt a ten-day progressive load protocol for athletes returning from a break. I based this on the precedent from the COVID-19 season, when football returned after a five-month suspension played in empty stadiums. At that time, I recorded that hamstring injuries in the 2026 V.League rose 40% year on year. The cause was not declining fitness, but load increases that were too fast when the schedule was compressed. That lesson applies to any sport with an interruption phase, including swimming. But at the swimming center, the response I received was hesitation. The reason given was very real: "If we slow the kids down, they won't make their targets." I understand this worry. It does not stem from ignorance, but from a system that rewards the short term. Youth results are measured by medals right now, while the cost of a damaged shoulder arrives three years later, when no one remembers. This is the root of the problem. The stadium is empty, the golden rule is bent, and the body pays the price. But in swimming, the "empty stadium" is not a crowdless grandstand. The "empty stadium" is the absence of data monitoring over the athlete's own body, throughout eleven months of training, day after day, when no camera is pointed at it. What is notable is that Vietnamese athletes are by no means weak in mental endurance. On the contrary, I have witnessed young athletes swimming through pain without telling anyone. Our sports culture still harbors a silent belief: pain is part of training, and reporting pain is weakness. This belief is more dangerous than any flawed training plan, because it neutralizes early warning signals. A body signaling pain is a body trying to talk. Muting it does not make it healthier. I remember an afternoon at a northern center, when a freestyle swimmer came to me with a shoulder that rose slightly when spreading the arms. I asked if it hurt. He replied: "Just a bit sore during the last two hundred meters." I suggested reducing shoulder volume for four days and replacing it with auxiliary exercises. He agreed. Four days later, the soreness disappeared. There was no miracle here. Just an early signal handled at the right moment. Had it dragged on two more weeks, we might have had one more tendinitis case in the statistics. This is why I always fight for a seemingly trivial principle: measure before pain. Not measure when pain occurs to handle it, but measure when there is no pain to predict it. In football, this principle has entered common practice in many places. In swimming, it remains unfamiliar. There is a technical difficulty peculiar to swimming that makes measurement more complex than football. In football, load comes mainly from running and can be measured by GPS with acceptable error. In swimming, load comes from water resistance, dependent on individual technique, arm span, stroke rate, and muscle strength. Two athletes swimming the same distance may bear loads differing by up to 30%. This means volume in meters is insufficient. At least one intensity indicator is needed, such as post-swim recovery heart rate, or pace per segment, or a rating of perceived exertion. I once built a simple cross-reference table for a group of seven athletes, consisting of three columns: daily swimming distance, rating of perceived exertion on a ten-point scale, and shoulder condition before and after each session. Over eight weeks, this table detected two cases of early overload that no one in the group had noticed through feel alone. Both had volume adjusted in time. This is proof that even a crude tool has value over having nothing. But I must admit something I always remind myself of: do not sink into a sea of numbers and forget the athlete. Numbers mean nothing if not paired with direct observation and interviews. A beautiful Excel sheet does not tell me the expression on a girl's face as she steps out of the pool. It does not tell me how many nights she slept before. It does not tell me the pressure from family or from her own expectations. The number is silent, but its sequence always knows how to tell a story. And the one who reads that sequence must be a human, not an algorithm. Here, I want to go against a trend currently fashionable in Vietnamese sports analysis. Many people now speak of data as a panacea, as if having machines would solve every injury problem. This is not true for swimming, and perhaps not true for any sport. Data is a tool, not a miracle. The biggest problem in Vietnamese swimming is not a lack of machines. The problem is a lack of a culture of record-keeping and a lack of patience with process. I once witnessed a center buy heart-rate monitors for all its athletes. Three months later, the devices sat in a drawer because no one maintained data uploads. Technology without process dies. And process without discipline is just formality. This is the lesson I learned from football, and it applies intact to swimming. So if I had to propose a roadmap for Vietnamese swimming, I would propose it in order of priority from low to high, not high to low. Step one: record swimming volume in meters and by intensity zone daily, even in a paper notebook. Step two: set a maximum weekly load-increase threshold during the base phase and follow it strictly. Step three: perform periodic shoulder mechanical screening, once every two weeks, using simple movements to detect imbalance. Step four: build a culture where reporting pain is not treated as weakness. Step five: only after the first four steps have become routine, consider equipment. This order matters more than any technology. There is a question I always ask myself after every injury I record: if we had the data, what would we do differently? The answer is usually very simple, sometimes disappointingly so. We would reduce volume for three days. We would change one exercise. We would let the athlete sleep one more hour. Those tiny changes, repeated steadily over years, are the entire difference between a sustainable career and broken shoulders at seventeen. I do not believe in great leaps in sports medicine. I believe in small adjustments maintained over a long time. That is why I am slow, and sometimes considered dry. But in return, I can look back over six years of data and point out exactly where the process was violated in more than two-thirds of the injuries I have recorded. That precision is worth more than any promise. Hai Phong, Moscow and COVID — three milestones that taught me injuries never repeat. Vietnamese swimming can learn from football without imitating football. We do not need massive analysis centers. We need a notebook, a pen, and someone patient enough to write in it every day. It may sound too simple for a complex problem. But in sports medicine, simple solutions are often the only ones that withstand the test of time. From Moscow to now, I have never seen an athlete escape decline through a miracle. What I have seen is curves that were managed, breaking points that were predicted, and shoulders saved by three well-timed days of slowing down. Vietnamese swimming deserves that kindness from its own system. The final question is not for the coaches, but for those building this discipline: if we know that most youth injuries begin with a single week of too-rapid load increase, why do we still measure a training center's progress by medals in three months, rather than by injuries in three years?