Most events at the Olympic Trials have 3 rounds, prelims, semis, and finals. For the first two rounds, the only thing that matters is qualifying for the next round. If they can afford to, top swimmers conserve energy in the earlier rounds by only going fast enough to safely make it back. Swimmers who qualify individually for the Olympics drop significantly more time from round to round than their nearest competitors. 2008 and 2012 Olympic Trials swimmers that finished 1st or 2nd improved their qualifying times from semis (or prelims for long events) in finals by medians of -1% for men and -.8% for women (negative percentages mean the swimmer got faster and a positive percentage means they got slower. 1:00.0 in semis, 59.4 in finals would be -1%). Swimmers that finished 3rd or 4th improved their qualifying times in finals by medians of -.4% for men and -.3% for women.
Swimmers that ended up 1st or 2nd also did less work in prelims to qualify for semifinals. 1st and 2nd place swimmers improved their prelim time in semis by medians of -1% for men and -.6% for women. 3rd and 4th place swimmers only improved in semis by medians of -.7% for men and -.5% for women.
3rd and 4th place swimmers went slower than their semi/prelim time in finals 26% of the time (12 men, 15 women). 1st and 2nd place swimmers went slower in finals only 13% of the time (5 men, 9 women, only once in an event longer than 100m).
This result makes sense for a couple reasons. Either a swimmer is clearly superior and can afford to slack off in early rounds. For example the 1st and 3rd place finishers in the 2008 men’s 200 fly:
| Finals | Semis | Prelims | |
| Michael Phelps | 1:52.20 | 1:54.02 | 1:55.85 |
| Davis Tarwater | 1:54.46 | 1:54.72 | 1:55.15 |
Or a race is close and the swimmer who performs better in finals wins. For example the 2nd and 3rd place finishers in the 2012 men’s 200 fly:
| Finals | Semis | Prelims | |
| Tyler Clary | 1:55.12 | 1:56.56 | 1:57.23 |
| Bobby Bollier | 1:55.79 | 1:56.06 | 1:56.69 |
Here’s a more detailed break down of median round to round time changes for the men:
| Final vs Semi (or 400/1500 prelim) | Semi vs Prelim | |||
| 1st & 2nd | 3rd & 4th | 1st & 2nd | 3rd & 4th | |
| All | -1.0% | -0.4% | -1.0% | -0.7% |
| 50 | -1.1% | -0.1% | -0.3% | -0.5% |
| 100 | -0.4% | -0.1% | -0.9% | -0.5% |
| 200 | -1.2% | -0.2% | -1.3% | -0.8% |
| 400 | -2.0% | -1.2% | ||
| 1500 | -1.6% | -0.6% |
And the women:
| Final vs Semi (or prelim for 400/1500) | Semi vs Prelim | |||
| 1st & 2nd | 3rd & 4th | 1st & 2nd | 3rd & 4th | |
| All | -0.8% | -0.3% | -0.6% | -0.5% |
| 50 | -0.4% | 0.2% | -0.3% | -0.5% |
| 100 | 0.0% | -0.1% | -0.4% | -0.3% |
| 200 | -0.7% | -0.3% | -0.8% | -0.6% |
| 400 | -1.3% | -0.5% | ||
| 800 | -1.4% | -1.0% |
The margin between rounds was often decisive. If the semi to final drops from the 2nd and 3rd place swimmers were reversed, the 3rd place swimmer beat the 2nd place swimmer 31% of the time (7 men, 9 women). (i.e.: swimmer A was 2nd and dropped -.5% and swimmer B was 3rd and added .5%. If instead swimmer A added .5% and swimmer B dropped -.5%, does swimmer B now beat swimmer A?)
A 3rd place swimmer’s semifinal time was faster than the 2nd place time in finals 2 times(2012 women’s 50 free and 2008 women’s 100 breast).
Here’s the raw round by round data:
| Men | Women | |||||||
| Event | Place | Year | Finals | Semifinals | Preliminaries | Finals | Semifinals | Preliminaries |
| 50 Free | 1 | 2008 | 21.47 | 21.83 | 22.05 | 24.25 | 24.38 | 24.72 |
| -1.6% | -1.0% | -0.5% | -1.4% | |||||
| 2012 | 21.59 | 22.08 | 22.09 | 24.5 | 24.56 | 24.55 | ||
| -2.2% | 0.0% | -0.2% | 0.0% | |||||
| 2 | 2008 | 21.65 | 21.65 | 21.68 | 24.82 | 24.48 | 24.63 | |
| 0.0% | -0.1% | 1.4% | -0.6% | |||||
| 2012 | 21.60 | 21.74 | 21.83 | 24.73 | 24.97 | 24.93 | ||
| -0.6% | -0.4% | -1.0% | 0.2% | |||||
| 3 | 2008 | 21.81 | 21.71 | 21.59 | 24.88 | 24.94 | 24.50 | |
| 0.5% | 0.6% | -0.2% | 1.8% | |||||
| 2012 | 21.68 | 21.81 | 22.06 | 24.78 | 24.72 | 24.75 | ||
| -0.6% | -1.1% | 0.2% | -0.1% | |||||
| 4 | 2008 | 21.91 | 21.94 | 21.89 | 24.9 | 24.70 | 25.04 | |
| -0.1% | 0.2% | 0.8% | -1.4% | |||||
| 2012 | 21.78 | 21.81 | 22.21 | 24.82 | 24.80 | 25.00 | ||
| -0.1% | -1.8% | 0.1% | -0.8% | |||||
| 100 Back | 1 | 2008 | 52.89 | 53.26 | 54.14 | 58.97 | 59.74 | 59.03 |
| -0.7% | -1.6% | -1.3% | 1.2% | |||||
| 2012 | 52.08 | 53.10 | 52.94 | 58.85 | 59.06 | 59.54 | ||
| -1.9% | 0.3% | -0.4% | -0.8% | |||||
| 2 | 2008 | 53.19 | 53.32 | 53.69 | 59.21 | 59.79 | 1:00.86 | |
| -0.2% | -0.7% | -1.0% | -1.8% | |||||
| 2012 | 52.86 | 53.40 | 53.96 | 59.49 | 59.1 | 59.69 | ||
| -1.0% | -1.0% | 0.7% | -1.0% | |||||
| 3 | 2008 | 53.37 | 53.37 | 53.96 | 59.42 | 59.48 | 59.15 | |
| 0.0% | -1.1% | -0.1% | 0.6% | |||||
| 2012 | 52.98 | 53.24 | 54.38 | 1:00.06 | 1:00.63 | 1:00.71 | ||
| -0.5% | -2.1% | -0.9% | -0.1% | |||||
| 4 | 2008 | 53.45 | 53.09 | 53.28 | 1:00.78 | 1:00.76 | 1:01.01 | |
| 0.7% | -0.4% | 0.0% | -0.4% | |||||
| 2012 | 53.03 | 53.52 | 54.21 | 1:00.46 | 59.82 | 1:00.60 | ||
| -0.9% | -1.3% | 1.1% | -1.3% | |||||
| 100 Breast | 1 | 2008 | 59.93 | 59.24 | 59.84 | 1:06.87 | 1:08.18 | 1:06.85 |
| 1.2% | -1.0% | -1.9% | 2.0% | |||||
| 2012 | 59.68 | 59.71 | 1:00.30 | 1:05.92 | 1:07.00 | 1:06.52 | ||
| -0.1% | -1.0% | -1.6% | 0.7% | |||||
| 2 | 2008 | 1:00.42 | 1:00.17 | 1:00.10 | 1:07.50 | 1:07.17 | 1:07.06 | |
| 0.4% | 0.1% | 0.5% | 0.2% | |||||
| 2012 | 1:00.15 | 1:00.27 | 1:00.87 | 1:05.99 | 1:05.82 | 1:06.33 | ||
| -0.2% | -1.0% | 0.3% | -0.8% | |||||
| 3 | 2008 | 1:00.59 | 1:00.94 | 1:00.98 | 1:07.51 | 1:07.19 | 1:07.86 | |
| -0.6% | -0.1% | 0.5% | -1.0% | |||||
| 2012 | 1:00.58 | 1:00.53 | 1:00.83 | 1:06.53 | 1:06.88 | 1:07.25 | ||
| 0.1% | -0.5% | -0.5% | -0.6% | |||||
| 4 | 2008 | 1:00.72 | 1:00.63 | 1:00.91 | 1:07.80 | 1:06.87 | 1:06.90 | |
| 0.1% | -0.5% | 1.4% | 0.0% | |||||
| 2012 | 1:00.68 | 1:00.20 | 1:00.48 | 1:07.19 | 1:07.64 | 1:07.72 | ||
| 0.8% | -0.5% | -0.7% | -0.1% | |||||
| 100 Fly | 1 | 2008 | 50.89 | 51.10 | 52.21 | 58.11 | 57.50 | 57.84 |
| -0.4% | -2.1% | 1.1% | -0.6% | |||||
| 2012 | 51.14 | 51.35 | 51.80 | 56.5 | 56.42 | 56.59 | ||
| -0.4% | -0.9% | 0.1% | -0.3% | |||||
| 2 | 2008 | 51.62 | 51.52 | 51.52 | 58.21 | 58.04 | 58.03 | |
| 0.2% | 0.0% | 0.3% | 0.0% | |||||
| 2012 | 51.32 | 51.88 | 51.87 | 57.57 | 58.53 | 57.82 | ||
| -1.1% | 0.0% | -1.6% | 1.2% | |||||
| 3 | 2008 | 52.08 | 51.86 | 52.26 | 58.36 | 58.31 | 58.44 | |
| 0.4% | -0.8% | 0.1% | -0.2% | |||||
| 2012 | 51.65 | 52.47 | 52.21 | 58.16 | 58.19 | 58.66 | ||
| -1.6% | 0.5% | -0.1% | -0.8% | |||||
| 4 | 2008 | 52.31 | 52.20 | 52.57 | 58.54 | 58.98 | 59.08 | |
| 0.2% | -0.7% | -0.7% | -0.2% | |||||
| 2012 | 51.86 | 51.89 | 52.18 | 58.22 | 58.53 | 58.67 | ||
| -0.1% | -0.6% | -0.5% | -0.2% | |||||
| 100 Free | 1 | 2008 | 47.92 | 48.35 | 47.78 | 53.78 | 53.76 | 54.57 |
| -0.9% | 1.2% | 0.0% | -1.5% | |||||
| 2012 | 48.10 | 48.33 | 49.17 | 53.96 | 54.27 | 54.52 | ||
| -0.5% | -1.7% | -0.6% | -0.5% | |||||
| 2 | 2008 | 48.05 | 47.58 | 48.15 | 53.83 | 53.66 | 53.64 | |
| 1.0% | -1.2% | 0.3% | 0.0% | |||||
| 2012 | 48.46 | 49.03 | 49.41 | 54.15 | 54.19 | 54.78 | ||
| -1.2% | -0.8% | -0.1% | -1.1% | |||||
| 3 | 2008 | 48.35 | 48.58 | 48.71 | 54.02 | 54.07 | 54.06 | |
| -0.5% | -0.3% | -0.1% | 0.0% | |||||
| 2012 | 48.55 | 48.71 | 49.24 | 54.30 | 54.23 | 54.49 | ||
| -0.3% | -1.1% | 0.1% | -0.5% | |||||
| 4 | 2008 | 48.46 | 48.89 | 48.89 | 54.62 | 54.45 | 54.81 | |
| -0.9% | 0.0% | 0.3% | -0.7% | |||||
| 2012 | 48.80 | 48.85 | 49.35 | 54.33 | 54.60 | 54.77 | ||
| -0.1% | -1.0% | -0.5% | -0.3% | |||||
| 200 Back | 1 | 2008 | 1:54.32 | 1:55.78 | 1:57.05 | 2:06.09 | 2:09.04 | 2:10.19 |
| -1.3% | -1.1% | -2.3% | -0.9% | |||||
| 2012 | 1:54.54 | 1:55.73 | 1:57.24 | 2:06.12 | 2:07.91 | 2:08.35 | ||
| -1.0% | -1.3% | -1.4% | -0.3% | |||||
| 2 | 2008 | 1:54.34 | 1:56.52 | 1:58.25 | 2:06.92 | 2:07.78 | 2:07.44 | |
| -1.9% | -1.5% | -0.7% | 0.3% | |||||
| 2012 | 1:54.88 | 1:55.88 | 1:57.93 | 2:07.58 | 2:08.41 | 2:09.35 | ||
| -0.9% | -1.7% | -0.6% | -0.7% | |||||
| 3 | 2008 | 1:57.35 | 1:57.30 | 1:57.60 | 2:07.69 | 2:08.28 | 2:08.76 | |
| 0.0% | -0.3% | -0.5% | -0.4% | |||||
| 2012 | 1:57.06 | 1:58.92 | 1:59.24 | 2:08.06 | 2:08.71 | 2:08.89 | ||
| -1.6% | -0.3% | -0.5% | -0.1% | |||||
| 4 | 2008 | 1:57.73 | 1:59.12 | 1:58.71 | 2:10.00 | 2:11.30 | 2:12.91 | |
| -1.2% | 0.3% | -1.0% | -1.2% | |||||
| 2012 | 1:57.39 | 1:57.39 | 1:59.03 | 2:09.52 | 2:09.03 | 2:10.35 | ||
| 0.0% | -1.4% | 0.4% | -1.0% | |||||
| 200 Breast | 1 | 2008 | 2:09.97 | 2:10.38 | 2:11.88 | 2:22.6 | 2:23.05 | 2:24.65 |
| -0.3% | -1.1% | -0.3% | -1.1% | |||||
| 2012 | 2:09.01 | 2:10.99 | 2:10.90 | 2:21.13 | 2:21.45 | 2:23.11 | ||
| -1.5% | 0.1% | -0.2% | -1.2% | |||||
| 2 | 2008 | 2:10.36 | 2:10.24 | 2:12.39 | 2:25.13 | 2:25.43 | 2:26.86 | |
| 0.1% | -1.6% | -0.2% | -1.0% | |||||
| 2012 | 2:09.97 | 2:10.01 | 2:10.30 | 2:23.03 | 2:24.12 | 2:24.95 | ||
| 0.0% | -0.2% | -0.8% | -0.6% | |||||
| 3 | 2008 | 2:11.00 | 2:11.63 | 2:11.41 | 2:25.98 | 2:27.15 | 2:27.41 | |
| -0.5% | 0.2% | -0.8% | -0.2% | |||||
| 2012 | 2:10.05 | 2:10.14 | 2:11.57 | 2:24.82 | 2:24.93 | 2:25.77 | ||
| -0.1% | -1.1% | -0.1% | -0.6% | |||||
| 4 | 2008 | 2:11.37 | 2:09.6 | 2:11.29 | 2:26.89 | 2:26.51 | 2:25.93 | |
| 1.4% | -1.3% | 0.3% | 0.4% | |||||
| 2012 | 2:10.25 | 2:10.45 | 2:12.14 | 2:25.56 | 2:25.41 | 2:26.23 | ||
| -0.2% | -1.3% | 0.1% | -0.6% | |||||
| 200 Fly | 1 | 2008 | 1:52.20 | 1:54.02 | 1:55.85 | 2:06.75 | 2:07.33 | 2:07.72 |
| -1.6% | -1.6% | -0.5% | -0.3% | |||||
| 2012 | 1:53.65 | 1:56.42 | 1:57.75 | 2:06.52 | 2:08.07 | 2:08.84 | ||
| -2.4% | -1.1% | -1.2% | -0.6% | |||||
| 2 | 2008 | 1:53.86 | 1:55.30 | 1:55.72 | 2:07.33 | 2:08.03 | 2:09.52 | |
| -1.2% | -0.4% | -0.5% | -1.2% | |||||
| 2012 | 1:55.12 | 1:56.56 | 1:57.23 | 2:07.72 | 2:08.61 | 2:10.25 | ||
| -1.2% | -0.6% | -0.7% | -1.3% | |||||
| 3 | 2008 | 1:54.46 | 1:54.72 | 1:55.15 | 2:08.48 | 2:08.86 | 2:09.37 | |
| -0.2% | -0.4% | -0.3% | -0.4% | |||||
| 2012 | 1:55.79 | 1:56.06 | 1:56.69 | 2:08.99 | 2:09.79 | 2:08.78 | ||
| -0.2% | -0.5% | -0.6% | 0.8% | |||||
| 4 | 2008 | 1:56.98 | 1:57.04 | 1:58.05 | 2:09.23 | 2:08.82 | 2:09.65 | |
| -0.1% | -0.9% | 0.3% | -0.6% | |||||
| 2012 | 1:56.83 | 1:56.10 | 1:59.35 | 2:09.45 | 2:09.59 | 2:09.48 | ||
| 0.6% | -2.7% | -0.1% | 0.1% | |||||
| 200 Free | 1 | 2008 | 1:44.10 | 1:45.64 | 1:46.63 | 1:55.88 | 1:57.10 | 1:57.72 |
| -1.5% | -0.9% | -1.0% | -0.5% | |||||
| 2012 | 1:45.70 | 1:46.27 | 1:48.31 | 1:54.40 | 1:55.59 | 1:58.02 | ||
| -0.5% | -1.9% | -1.0% | -2.1% | |||||
| 2 | 2008 | 1:45.85 | 1:46.08 | 1:47.04 | 1:55.92 | 1:57.92 | 1:58.76 | |
| -0.2% | -0.9% | -1.7% | -0.7% | |||||
| 2012 | 1:45.75 | 1:46.25 | 1:48.14 | 1:56.79 | 1:58.04 | 1:58.62 | ||
| -0.5% | -1.7% | -1.1% | -0.5% | |||||
| 3 | 2008 | 1:46.14 | 1:46.77 | 1:47.72 | 1:56.73 | 1:58.48 | 1:59.18 | |
| -0.6% | -0.9% | -1.5% | -0.6% | |||||
| 2012 | 1:46.56 | 1:47.49 | 1:48.95 | 1:57.47 | 1:57.81 | 1:58.34 | ||
| -0.9% | -1.3% | -0.3% | -0.4% | |||||
| 4 | 2008 | 1:46.20 | 1:46.78 | 1:47.78 | 1:57.93 | 1:58.50 | 1:59.09 | |
| -0.5% | -0.9% | -0.5% | -0.5% | |||||
| 2012 | 1:46.64 | 1:47.38 | 1:48.42 | 1:57.75 | 1:58.28 | 1:59.13 | ||
| -0.7% | -1.0% | -0.4% | -0.7% | |||||
| 200 IM | 1 | 2008 | 1:54.80 | 1:58.05 | 1:59.70 | 2:09.71 | 2:09.94 | 2:12.02 |
| -2.8% | -1.4% | -0.2% | -1.6% | |||||
| 2012 | 1:54.84 | 1:56.66 | 1:59.27 | 2:10.22 | 2:10.51 | 2:12.38 | ||
| -1.6% | -2.2% | -0.2% | -1.4% | |||||
| 2 | 2008 | 1:55.22 | 1:57.57 | 1:59.49 | 2:10.32 | 2:11.72 | 2:12.21 | |
| -2.0% | -1.6% | -1.1% | -0.4% | |||||
| 2012 | 1:54.93 | 1:55.51 | 1:59.92 | 2:11.30 | 2:12.32 | 2:13.58 | ||
| -0.5% | -3.7% | -0.8% | -0.9% | |||||
| 3 | 2008 | 1:58.15 | 2:00.74 | 2:01.54 | 2:10.4 | 2:10.85 | 2:12.38 | |
| -2.1% | -0.7% | -0.3% | -1.2% | |||||
| 2012 | 1:58.92 | 1:58.32 | 1:59.11 | 2:11.55 | 2:11.37 | 2:13.89 | ||
| 0.5% | -0.7% | 0.1% | -1.9% | |||||
| 4 | 2008 | 2:00.06 | 2:00.93 | 2:01.06 | 2:11.28 | 2:11.76 | 2:13.30 | |
| -0.7% | -0.1% | -0.4% | -1.2% | |||||
| 2012 | 1:59.58 | 1:59.87 | 1:59.65 | 2:12.26 | 2:12.62 | 2:14.19 | ||
| -0.2% | 0.2% | -0.3% | -1.2% | |||||
| 400 Free | 1 | 2008 | 3:43.53 | 3:48.28 | 4:02.32 | 4:05.61 | ||
| -2.1% | -1.3% | |||||||
| 2012 | 3:47.67 | 3:49.16 | 4:02.84 | 4:05.60 | ||||
| -0.7% | -1.1% | |||||||
| 2 | 2008 | 3:43.73 | 3:48.06 | 4:03.92 | 4:06.04 | |||
| -1.9% | -0.9% | |||||||
| 2012 | 3:47.83 | 3:48.37 | 4:04.18 | 4:07.91 | ||||
| -0.2% | -1.5% | |||||||
| 3 | 2008 | 3:43.92 | 3:48.25 | 4:05.05 | 4:05.72 | |||
| -1.9% | -0.3% | |||||||
| 2012 | 3:48.17 | 3:49.43 | 4:05 | 4:05.78 | ||||
| -0.5% | -0.3% | |||||||
| 4 | 2008 | 3:46.36 | 3:49.92 | 4:05.09 | 4:06.74 | |||
| -1.5% | -0.7% | |||||||
| 2012 | 3:48.32 | 3:48.48 | 4:07.27 | 4:09.83 | ||||
| -0.1% | -1.0% | |||||||
| 400 IM | 1 | 2008 | 4:05.25 | 4:13.43 | 4:31.12 | 4:34.59 | ||
| -3.2% | -1.3% | |||||||
| 2012 | 4:07.06 | 4:10.66 | 4:31.74 | 4:35.72 | ||||
| -1.4% | -1.4% | |||||||
| 2 | 2008 | 4:06.08 | 4:13.38 | 4:32.87 | 4:35.76 | |||
| -2.9% | -1.0% | |||||||
| 2012 | 4:07.89 | 4:14.72 | 4:34.48 | 4:39.57 | ||||
| -2.7% | -1.8% | |||||||
| 3 | 2008 | 4:13.85 | 4:15.10 | 4:35.73 | 4:37.19 | |||
| -0.5% | -0.5% | |||||||
| 2012 | 4:09.92 | 4:15.88 | 4:38.62 | 4:39.84 | ||||
| -2.3% | -0.4% | |||||||
| 4 | 2008 | 4:14.13 | 4:17.46 | 4:38.54 | 4:38.96 | |||
| -1.3% | -0.2% | |||||||
| 2012 | 4:16.07 | 4:19.19 | 4:38.67 | 4:43.07 | ||||
| -1.2% | -1.6% | |||||||
| 1500/800 Free | 1 | 2008 | 14:45.54 | 15:06.24 | 8:20.81 | 8:29.91 | ||
| -2.3% | -1.8% | |||||||
| 2012 | 14:52.19 | 14:57.29 | 8:19.78 | 8:27.91 | ||||
| -0.6% | -1.6% | |||||||
| 2 | 2008 | 14:50.8 | 15:11.99 | 8:25.38 | 8:29.39 | |||
| -2.3% | -0.8% | |||||||
| 2012 | 14:52.51 | 14:59.97 | 8:21.87 | 8:27.61 | ||||
| -0.8% | -1.1% | |||||||
| 3 | 2008 | 14:57.50 | 15:02.78 | 8:31.23 | 8:35.58 | |||
| -0.6% | -0.8% | |||||||
| 2012 | 14:57.53 | 15:10.38 | 8:26.60 | 8:33.53 | ||||
| -1.4% | -1.3% | |||||||
| 4 | 2008 | 15:07.78 | 14:50.24 | 8:31.47 | 8:37.65 | |||
| 2.0% | -1.2% | |||||||
| 2012 | 15:03.37 | 15:08.93 | 8:28.12 | 8:29.01 | ||||
| -0.6% | -0.2% |
Really good info! What I would love to see is an article about how warm ups, warm downs, rest between sessions are all managed. For example, what type of warm up does a top 5 finisher in a 50 free do vs the 800. I’ve looked all over but I’ve never found this anywhere.
Nice work team analysis!
I wonder, especially in the shorter races, how much energy is really saved going 1% slower. Is 24.5 really that much easier than 24.8? I know some of the top swimmers like Phelps and Lochte can shut it down if they are out ahead in races like a 200 IM, but most qualifiers don’t have that luxury. I hypothesis that the real difference isn’t that those that qualified had more energy saved up from dogging the earlier rounds but that those swimmers just handled the pressure and stepped it up better each round. Regardless of the causation, this is a very interesting phenomenon. Thanks for the article!