An Se-young, ranked first in the world in women's badminton singles, has compiled 49 wins and one loss this season, widening her ranking lead as international results accumulate.

At an open session at the national training centre in Jincheon, what stood out was neither special equipment nor new technique, but the practice of completing every prescribed repetition down to the last.

Conditioning holds up technique

Singles badminton loads the legs more heavily the longer a rally runs. When footwork slows by half a beat late in a match, the same shot stops working.

That is why so much of the training is devoted to changes of direction and landing stability on court, with landing work weighted more heavily for players with a history of injury.

Reading the record

Forty-nine wins to one looks overwhelming, but badminton players contest several matches per tournament, so wins accumulate quickly. What matters is the stage at which the loss occurred.

The substance of the record is the near-absence of upsets before finals. A world number one who does not wobble in early rounds is one whose condition is being managed consistently.

The next target is the season's later tournaments. The national team said it was balancing scheduling with recovery management.