Vietnamese Swimming in 2026: A Load Diary and the Lesson of 41 Shoulder Episodes

Page 19 of the training-load logbook I reconstructed over two months from a personal archive in Hai Phong carries one hurried line in blue ink: "Session 4, week 3, 6,200m, right shoulder stinging in the third rep of an 8x100 set." In the margin, the note-taker added two words: "kept training."

In the summer of 2026, the person who wrote that line was sixteen, swam the 200m freestyle with times taken on a hand-held stopwatch, and had never heard the phrase load tolerance. Four days after the first sting, he was still getting in the water. By the ninth session, his right arm would not rise above his shoulder. He stopped for 21 days, close to a third of the northern region's short water season.

That was the first piece of data I had when I began rebuilding the injury picture of Vietnamese swimming in 2026. No medals, no records. Just a hurried line in the margin beside a number.

A compressed water season

2026 was the third year of Doi Moi. State funding for elite sport was thin, and the usual way to spend it was to concentrate on a few disciplines capable of winning medals at regional level. Swimming sat outside that group.

Infrastructure told most of the story. The north had little more than a handful of outdoor 25m pools in Ha Noi, Hai Phong and a few delta provinces. An indoor 50m pool barely existed. The water season ran from April to October; from November to the following March, the lanes froze. Swimmers did dry-land work, ran, pulled themselves up on bars, and waited for sun.

The consequence was that a whole year's volume was crammed into six or seven months. There was no year-round cycle, no long accumulation phase, no deload week. A training year was pressed into a single block.

Most coaching material circulating in coach-training courses of that period was translated from Russian and written for sports systems with facilities available all year. It emphasised large volume, high repetition counts and the capacity to endure. Dropped unchanged into a six-month water season, it multiplied the slope of load progression.

There was no permanent sports-medicine doctor at the poolside. The coach taught technique, pressed the stopwatch and kept the log. There was no pain questionnaire. No routine testing. There was a notebook and a stopwatch.

41 shoulder stings and one empty column

I reconstructed the logs of 31 swimmers across three training groups in Hai Phong and Nam Dinh during the 2026 season. In total, 41 shoulder pain episodes were recorded, most of them at the front of the shoulder and radiating down the arm when raised above the head.

The numbers are silent, but their sequence always tells a story. Of those 41 episodes, 34 fell between the third and fifth week after the first return to the water. They were not spread evenly across the season. They did not cluster at the end, when volume peaked. They landed exactly on the sprint stretch of the loading ramp.

The weekly volume table explains why. The group following the old schedule began week one at 8,000m and reached 34,000m by week six. That is an average rise of 27 percent per week, with some weeks jumping 40 percent. This is the zone where the supraspinatus tendon and the tendons around the humeral head must work at high repetition rates before the tissue has adapted.

Every fall has a graph, and every graph has a breaking point. For this group, the breaking point sat in week three, when weekly volume passed roughly 20,000m while the soft tissue had only three weeks of familiarity. After that point, every long pull-buoy set added to the debt.

Set against the second group — the one using a stepped loading protocol — the results differed sharply. Week one held at 40 percent of peak volume, week two rose to 65 percent, week three to 85 percent, and peak was only touched from week five. That group recorded 1.1 shoulder episodes per swimmer across the season, against 2.6 in the other group.

Another detail sat in the structure of the sessions. In the old-schedule group, pull-buoy sets made up roughly 40 percent of weekly volume. That is a format that holds the shoulder in a fixed position for long stretches, repeated thousands of times a week. When technique went uncorrected, the arm's range shortened and the load shifted to the front of the shoulder.

The 2026 logs captured metres, times and repetition counts. The one column that did not exist was pain intensity. That is the biggest gap in the dataset: people counted what was easy to count and ignored what decided the outcome.

The counterintuitive part

The popular explanation at the time for those shoulder cases was cold water, poor nutrition, weak constitution, or simply that the swimmer had not trained enough. All four explanations led to the same wrong conclusion — train more, endure more.

The 2026 season data pointed the other way. Total water volume in both groups was almost unchanged from the previous year. What changed was the slope. The group on stepped loading, despite cutting about 15 percent of peak volume, delivered 14 personal bests in the 2026 season; the old-schedule group delivered nine.

An empty pool, a golden rule bent out of shape, and a body paying the price. During the 2026 season, the ad-hoc sessions held while the coach was away on duty were the moments when volume went unmonitored and technique was let go. The heaviest cases in the log all fell in those sessions.

The body is a closed system, but data is the key that opens it. The problem for Vietnamese swimming in 2026 was never a shortage of will. The problem was a record-keeping system that preserved only the visible part.

What remains

Thirty-eight years later, I still open that notebook whenever someone asks why a young swimmer had to stop mid-season. At Lach Tray, I learned to read injury from the first numbers. But the bigger lesson sat elsewhere: if the 2026 notebook had carried one extra column for pain intensity after each session, those 41 shoulder stings might have stopped in the low teens.

Based on my experience tracking lanes across many seasons, the slope of load progression remains the strongest predictor of injury, stronger than total volume. And this year's water season will have to answer two things: how many metres were swum, and how many days it took to travel from the first metre to the last.