Now that the worst kept secret in swimming has been revealed and Michael Phelps is officially back in the water, let’s take a look at how his 100 Butterfly from this past weekend’s Mesa Grand Prix stacks up to some past performances.

As many of you know, at the 2012 Olympics Phelps became the first swimmer to win three consecutive Gold Medals in the same event with his 100M Butterfly victory. And looking back, that makes perfect sense as he has owned the 100 Butterfly for as long as he has been swimming it. He broke the LCM National Age Group record as an 8 & Under with a time of 1:08.15 (if my memory serves correct), which stood until not long ago, and never looked back. On a personal note, I had my first shot at Phelps in 1996 when he and I 'raced' at a Dynamo meet in Atlanta, but unfortunately he beat me by a 25.  

But, relatively speaking, it wasn’t easy. Phelps’ average margin of victory across the 2004, 2008, and 2012 100M Butterfly finals was only 0.09 seconds, or 0.18% (second amongst male 100M stroke finals to the 100M freestyle at 0.13%). ⁽¹⁾

Here is a look at Phelps’ times vs. the second place finisher from each of the past three Olympiads:

So how did he do this? Consistency. Phelps undoubtedly got stronger over those eight years, and as a result his splits improved, but strategy isn’t all about time. What was consistent was his stroke count.

In 2004, Phelps took 17 strokes his first 50 and 19 strokes his second. In 2008 he ‘improved’ to 16.50 strokes (i.e. there was a bit of a glide after his 16^th stroke) in his first 50 while remaining at 19 strokes his second. And in 2012, he repeated his 16.5 strokes and lowered his second to 18.5

Also worth noting, his underwater kicks increased from 8 to 10 on his first lap and 9 to 11 on his second. Although I admit this stat was a little difficult to validate as the camera was not always focused on Phelps.

For comparison purposes, Michael Cavic, who takes more kicks underwater (averaging two more per lap but with a smaller wavelength than Phelps), managed to increase his stroke count from 2008 to 2012. In 2008, he took 16 strokes his first lap and 18.5 strokes his second. In fact, you could argue with how infamous his glide to the finish has become it could be considered more like 18.999999 strokes. Either way, in 2012, he increased his first lap to 17.5 (maybe 18, poor video feed) and his second to 20. The result was a 51.81, tied for fourth place.

Eight years of growing up and Phelps didn’t stray at all really from the 100M Butterfly that he knew best, so it isn’t surprising that even after nearly two years without competing, at the Mesa Grand Prix Phelps took 16.5 strokes his first lap and 18.5 his second.

His time was of course a bit slower, ~3.1% off his PR, so we can expect that to change a bit, but don’t expect much else about his race to change.

Here is a look at Phelps’ times vs. the second place finisher from each of the past three Olympiads:

Appendix: A Comparison of Phelps’ 100M Butterfly Stroke Count Over the Years

Source: Omega Timing, 2004 Olympics, 2008 Olympics, 2012 Olympics, 2014 MGP

1. Third is the 100 breaststroke at 0.52% and fourth is the 100 backstroke at 1.01%