Katie Ledecky entered the world stage of swimming at the 2012 London Olympic Games by winning the 800 m freestyle in a time of 8:14.63, just short of Rebecca Adlington's world record. The quality of the original film used for this analysis was not good and so some finer points of the swimmer's technique are obscured.

This stroke analysis includes a moving sequence in real time, a moving sequence where each frame is displayed for .5 of a second, and still frames. The time between each frame used in this analysis was .12 seconds.

The following image sequence is in real time. It will play through 10 times and then stop. To repeat the sequence, click the browser's "refresh" or "reload" button.

The following image sequence shows each frame for half a second. It will play through 10 times and then stop. To repeat the sequence, click the browser's "refresh" or "reload" button.

At the end of the following narrative, each frame is illustrated in detail in a sequential collage.

Notable Features


This view of Katie Ledecky's crawl stroke is more than 2.5 years old. It also illustrates the stage of an 800 m race where fatigue starts to impinge upon the technique of a swimmer. What is shown here should be compared to more recent videos. The main features that detract from the velocity of forward progression in this swimmer's stroke follow.

  1. The rise and fall of the head and upper body in the breathing action. That should be removed and replaced with only a head movement that rotates on the longitudinal axis to inhale in the bow wave. The disruption of streamline on every breath produces a negative resistive force that slows the swimmer. When that deceleration is multiplied by the number of breaths taken in an 800 m event, it is quite substantial.
  2. The catch-up stroke should be replaced with a balanced stroke. That would eliminate the inertial lags which over 800 m amount to a considerable amount of lost time, that is, time when propulsion could be developed.
  3. The kick should be much smaller. It is difficult to discern if the arm stroke actions are influenced by the large kick or if the arms influence the kick. However, the legs attain positions where they develop detrimental resistance, a further negative influence on progression. The legs never attain a position where they might create even a very small brief propulsive force. Unlike many female distance swimmers, Katie Ledecky used a 4-beat kick in this sequence.