swimstats

Mackenzie O'Brien

FCZINMIMRSDMIMMAWILL

228 plausible swims · 37 meets · 2023-01-07 → 2026-10-10

Personal records

EventCourseBest CutDateMeet
50 Freestyle SCY 23.68 Sectionals ✓+1.19s to US Open 2026-10-10 2026 HS Girls MISCA Meetfast pool
100 Freestyle SCY 53.02 Sectionals ✓+4.03s to US Open 2026-02-08 2026 Grand Rapids Openvenue
200 Freestyle SCY 1:58.70 +0.81s to Sectionals 2026-02-07 2026 Grand Rapids Openvenue
500 Freestyle SCY 5:31.01 +16.02s to Sectionals 2026-02-08 2026 Grand Rapids Openvenue
1650 Freestyle SCY 20:07.22 +110.73s to Sectionals 2024-11-01 Greater Kalamazoo Arena Challengevenue
50 Backstroke SCY 27.37 +0.08s to Sectionals 2026-03-01 2026 JAWS "Last Chance" Meetvenue
100 Backstroke SCY 59.13 Sectionals ✓+6.14s to US Open 2026-02-08 2026 Grand Rapids Openvenue
200 Backstroke SCY 2:11.14 Sectionals ✓+15.75s to US Open 2026-03-01 2026 JAWS "Last Chance" Meetvenue
50 Breaststroke SCY 31.49 +0.80s to Sectionals 2026-03-01 2026 JAWS "Last Chance" Meetvenue
100 Breaststroke SCY 1:10.88 +1.39s to Sectionals 2026-02-07 2026 Grand Rapids Openvenue
200 Breaststroke SCY 2:35.54 +4.55s to Sectionals 2026-02-08 2026 Grand Rapids Openvenue
50 Butterfly SCY 25.98 Sectionals ✓+1.89s to US Open 2026-02-28 2026 JAWS "Last Chance" Meetvenue
100 Butterfly SCY 56.48 Sectionals ✓+3.69s to US Open 2026-10-10 2026 HS Girls MISCA Meetfast pool
200 Butterfly SCY 2:17.22 +4.13s to Sectionals 2026-03-07 2026 Lake Superior Regional Meetvenue
100 Individual Medley SCY 59.25 2026-02-28 2026 JAWS "Last Chance" Meetvenue
200 Individual Medley SCY 2:12.68 Sectionals ✓+14.29s to US Open 2026-03-01 2026 JAWS "Last Chance" Meetvenue
400 Individual Medley SCY 4:53.79 +9.80s to Sectionals 2025-12-05 EGRA 2025 Winter Washoutvenue
50 Freestyle LCM 26.91 Sectionals ✓+0.72s to US Open 2026-07-25 2026 MI LCM ULTRA Championship Meetvenue
100 Freestyle LCM 59.66 Sectionals ✓+2.87s to US Open 2026-07-24 2026 MI LCM ULTRA Championship Meetvenue
200 Freestyle LCM 2:17.05 +3.96s to Sectionals 2026-07-11 2026 West Michigan Classicvenue
400 Freestyle LCM 5:08.44 +26.05s to Sectionals 2025-06-14 2025 JAWS Sun & Funvenue
800 Freestyle LCM 10:43.63 +62.24s to Sectionals 2025-06-21 2025 Summer Solstice Meetvenue
1500 Freestyle LCM 20:24.01 +107.52s to Sectionals 2024-06-14 JAWS Sun & Funvenue
50 Backstroke LCM 30.54 Sectionals ✓+1.35s to US Open 2026-07-24 2026 MI LCM ULTRA Championship Meetvenue
100 Backstroke LCM 1:06.51 Sectionals ✓+3.22s to US Open 2026-07-26 2026 MI LCM ULTRA Championship Meetvenue
200 Backstroke LCM 2:43.40 +12.01s to Sectionals 2025-06-22 2025 Summer Solstice Meetvenue
50 Breaststroke LCM 37.00 +1.41s to Sectionals 2026-06-06 MLA Big Red Challengevenue
100 Breaststroke LCM 1:24.45 +4.46s to Sectionals 2026-06-07 MLA Big Red Challengevenue
200 Breaststroke LCM 3:17.55 +24.76s to Sectionals 2025-06-14 2025 JAWS Sun & Funvenue
50 Butterfly LCM 28.93 Sectionals ✓+0.74s to US Open 2026-07-26 2026 MI LCM ULTRA Championship Meetvenue
100 Butterfly LCM 1:05.72 Sectionals ✓+4.33s to US Open 2026-03-27 2026 Central Zone East Spring Speedo Sectionavenue
200 Butterfly LCM 2:41.13 +9.14s to Sectionals 2026-07-12 2026 West Michigan Classicvenue
200 Individual Medley LCM 2:33.04 +1.75s to Sectionals 2026-07-12 2026 West Michigan Classicvenue
400 Individual Medley LCM 5:43.02 +18.63s to Sectionals 2025-06-13 2025 JAWS Sun & Funvenue

National cuts (Sectionals → Nationals) are the current-season meet qualifying times for the swimmer's zone and age group; ✓ marks the hardest cut already achieved.

Pool tags are a venue speed heuristic (median deviation of all swims there vs each swimmer's typical time) — see the venue page for the method.

Fastest relay legs

LegCourseTime StartRelayDateMeet
50 Freestyle SCY 24.68 flat 200 Free Relay 2025-12-06 EGRA 2025 Winter Washout
50 Freestyle SCY 23.73 flying 200 Free Relay (leg 4) 2025-10-18 2025 HS Girls MISCA Meet
100 Freestyle SCY 52.11 flat 400 Free Relay 2026-10-10 2026 HS Girls MISCA Meet
100 Freestyle SCY 52.40 flying 400 Free Relay (leg 4) 2025-10-18 2025 HS Girls MISCA Meet
50 Backstroke SCY 29.85 flat 200 Medley Relay 2025-03-09 2025 SCY MAGS Championship Meet
100 Backstroke SCY 1:02.33 flat 400 Medley Relay 2025-03-22 2025 ULTRA Championship Meet
50 Butterfly SCY 25.14 flying 200 Medley Relay (leg 3) 2026-10-10 2026 HS Girls MISCA Meet
50 Freestyle LCM 27.33 flat 200 Free Relay 2026-07-26 2026 MI LCM ULTRA Championship Meet
50 Freestyle LCM 27.35 flying 200 Free Relay (leg 4) 2025-08-08 2025 Central Zone 14 & Under Championship Mee
50 Freestyle LCM 29.66 flying 200 Medley Relay (leg 4) 2024-07-28 2024 LCM ULTRA Championship Meet
100 Freestyle LCM 1:02.29 flat 400 Free Relay 2025-08-10 2025 Central Zone 14 & Under Championship Mee
100 Freestyle LCM 1:00.28 flying 400 Free Relay (leg 4) 2026-07-25 2026 MI LCM ULTRA Championship Meet
50 Butterfly LCM 28.70 flying 200 Medley Relay (leg 3) 2026-07-24 2026 MI LCM ULTRA Championship Meet
100 Butterfly LCM 1:06.94 flying 400 Medley Relay (leg 3) 2026-07-25 2026 MI LCM ULTRA Championship Meet

Reconstructed from relay split marks. Flat = lead-off (comparable to individual times); flying starts run ~0.5–0.7s fast and are not PRs.

PR splits

100 Freestyle SCY 53.02

25.54
27.48

Front half 25.54s · back half 27.48s

200 Freestyle SCY 1:58.70

27.97
29.90
30.25
30.58

Front half 57.87s · back half 60.83s

500 Freestyle SCY 5:31.01

28.81
32.27
32.87
33.58
33.52
34.13
34.08
34.33
34.27
33.15

Front half 161.05s · back half 169.96s

1650 Freestyle SCY 20:07.22

31.06
34.92
35.91
35.88
35.80
36.34
36.35
36.45
36.87
36.81
37.20
37.05
37.05
37.27
37.02
37.56
37.27
37.04
37.89
36.99
37.49
37.64
37.32
37.69
37.26
37.37
37.14
37.13
37.28
35.85
36.22
36.13
33.97

100 Backstroke SCY 59.13

28.65
30.48

Front half 28.65s · back half 30.48s

200 Backstroke SCY 2:11.14

30.18
32.40
34.30
34.26

Front half 62.58s · back half 68.56s

100 Breaststroke SCY 1:10.88

32.96
37.92

Front half 32.96s · back half 37.92s

200 Breaststroke SCY 2:35.54

34.89
40.02
40.48
40.15

Front half 74.91s · back half 80.63s

100 Butterfly SCY 56.48

26.52
29.96

Front half 26.52s · back half 29.96s

200 Butterfly SCY 2:17.22

28.32
33.96
36.59
38.35

Front half 62.28s · back half 74.94s

100 Individual Medley SCY 59.25

26.61
32.64

Front half 26.61s · back half 32.64s

200 Individual Medley SCY 2:12.68

27.63
32.31
40.65
32.09

Front half 59.94s · back half 72.74s

400 Individual Medley SCY 4:53.79

29.51
34.59
36.39
36.41
42.70
44.09
35.56
34.54

Front half 136.90s · back half 156.89s

100 Freestyle LCM 59.66

28.90
30.76

Front half 28.90s · back half 30.76s

200 Freestyle LCM 2:17.05

31.54
34.84
35.43
35.24

Front half 66.38s · back half 70.67s

400 Freestyle LCM 5:08.44

35.45
38.31
40.05
39.27
40.31
39.34
40.03
35.68

Front half 153.08s · back half 155.36s

800 Freestyle LCM 10:43.63

36.90
38.95
41.24
39.48
41.86
40.26
41.78
40.55
41.91
40.33
37.17
45.30
36.53
45.17
37.11
39.09

Front half 321.02s · back half 322.61s

1500 Freestyle LCM 20:24.01

36.35
38.91
42.13
40.85
41.95
40.97
41.73
40.86
38.92
44.33
41.34
40.57
42.46
41.46
38.96
43.83
42.47
40.64
42.37
40.37
41.94
40.52
41.58
40.27
41.36
40.51
39.53
38.87
39.89
38.07

Front half 611.79s · back half 612.22s

100 Backstroke LCM 1:06.51

32.07
34.44

Front half 32.07s · back half 34.44s

200 Backstroke LCM 2:43.40

38.23
42.86
41.05
41.26

Front half 81.09s · back half 82.31s

100 Breaststroke LCM 1:24.45

39.26
45.19

Front half 39.26s · back half 45.19s

200 Breaststroke LCM 3:17.55

45.33
50.01
52.86
49.35

Front half 95.34s · back half 102.21s

100 Butterfly LCM 1:05.72

30.10
35.62

Front half 30.10s · back half 35.62s

200 Butterfly LCM 2:41.13

34.60
40.42
43.02
43.09

Front half 75.02s · back half 86.11s

200 Individual Medley LCM 2:33.04

32.51
37.87
46.90
35.76

Front half 70.38s · back half 82.66s

400 Individual Medley LCM 5:43.02

35.23
41.39
44.70
42.95
51.10
50.07
40.47
37.11

Front half 164.27s · back half 178.75s

Reaction time

fastest 0.64s average 0.645s slowest 0.65s 2 electronic starts

Start reaction over time faster starts higher

From electronically-timed starts only (~2% of corpus swims carry a reaction time). PRs with a recorded reaction show an RT chip in the splits section above.

Swim history

Every recorded swim, newest first
DateEventCourse TimeAge RoundMeet

Individual swims with a recorded date and time — including disqualifications — plus reconstructed relay legs (marked). Assembled in the browser from this page’s data.

Progression

Faster times are higher. One card per event, all courses & history.

50 Freestyle SCY 23.68 8 swims
100 Freestyle SCY 53.02 6 swims
200 Freestyle SCY 1:58.70 6 swims
500 Freestyle SCY 5:31.01 3 swims
1650 Freestyle SCY 20:07.22 2 swims
50 Backstroke SCY 27.37 4 swims
100 Backstroke SCY 59.13 3 swims
200 Backstroke SCY 2:11.14 4 swims
50 Breaststroke SCY 31.49 2 swims
100 Breaststroke SCY 1:10.88 4 swims
200 Breaststroke SCY 2:35.54 3 swims
50 Butterfly SCY 25.98 6 swims
100 Butterfly SCY 56.48 5 swims
200 Butterfly SCY 2:17.22 3 swims
100 Individual Medley SCY 59.25 6 swims
200 Individual Medley SCY 2:12.68 6 swims
400 Individual Medley SCY 4:53.79 2 swims
50 Freestyle LCM 26.91 25 swims
100 Freestyle LCM 59.66 14 swims
200 Freestyle LCM 2:17.05 6 swims
400 Freestyle LCM 5:08.44 3 swims
800 Freestyle LCM 10:43.63 2 swims
1500 Freestyle LCM 20:24.01 1 swim
50 Backstroke LCM 30.54 14 swims
100 Backstroke LCM 1:06.51 17 swims
200 Backstroke LCM 2:43.40 4 swims
50 Breaststroke LCM 37.00 6 swims
100 Breaststroke LCM 1:24.45 6 swims
200 Breaststroke LCM 3:17.55 2 swims
50 Butterfly LCM 28.93 19 swims
100 Butterfly LCM 1:05.72 18 swims
200 Butterfly LCM 2:41.13 2 swims
200 Individual Medley LCM 2:33.04 10 swims
400 Individual Medley LCM 5:43.02 2 swims