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BOSTON MARATHON 2025

Marilia Serizawa

Bib: 9813•F

0:00
0:00
/ mi
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Overall
#0 / 28404
Top 18%
Gender (Female)
#0 / 12228
Top 4%
Division (F18-39)
#0 / 5469
Top 8%
Race Day Weather
50°/40°F
broken clouds

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
21:38
Rank: #7537
Start → 5K
21:38 | 6:58/mi
10K· 6.21 mi
43:15
Rank: #7593 (-56)
5K → 10K
21:37 | 6:57/mi
15K· 9.32 mi
1:04:45
Rank: #7417 (+176)
10K → 15K
21:30 | 6:55/mi
20K· 12.43 mi
1:26:12
Rank: #7109 (+308)
15K → 20K
21:27 | 6:54/mi
Half· 13.11 mi
1:30:52
Rank: #7063 (+46)
20K → Half
4:40 | 6:50/mi
25K· 15.53 mi
1:47:31
Rank: #6735 (+328)
Half → 25K
16:39 | 6:52/mi
30K· 18.64 mi
2:09:25
Rank: #6282 (+453)
25K → 30K
21:54 | 7:03/mi
20M
2:19:01
Rank: #6072 (+210)
30K → 20M
9:36 | 7:04/mi
21M
2:26:19
Rank: #5857 (+215)
20M → 21M
7:18 | 7:18/mi
35K· 21.75 mi
2:31:33
Rank: #5818 (+39)
21M → 35K
5:14 | 7:00/mi
23M
2:40:31
Rank: #5671 (+147)
35K → 23M
8:58 | 7:10/mi
24M
2:47:21
Rank: #5526 (+145)
23M → 24M
6:50 | 6:50/mi
40K· 24.85 mi
2:53:19
Rank: #5422 (+104)
24M → 40K
5:58 | 6:59/mi
25.2M
2:55:55
Rank: #5364 (+58)
40K → 25.2M
2:36 | 7:32/mi
Finish· 26.22 mi
3:02:39
Rank: #5245 (+119)
25.2M → Finish
6:44 | 6:36/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:30:52
Pace6:56 /mi
2nd Half
Distance13.11 mi
Time1:31:47
Pace7:00 /mi
📊Positive Split: 1.0% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:47:3821:386:5821:38
6:58
-
10K
6.21 mi11:09:1543:156:5821:37
6:57
-0:01
15K
9.32 mi11:30:451:04:456:5721:30
6:55
-0:02
20K
12.43 mi11:52:121:26:126:5621:27
6:54
-0:01
Half
13.11 mi11:56:521:30:526:564:40
6:50
-0:04
25K
15.53 mi12:13:311:47:316:5516:39
6:52
+0:02
30K
18.64 mi12:35:252:09:256:5721:54
7:03
+0:11
20M
20.00 mi12:45:012:19:016:579:36
7:04
+0:01
21M
21.00 mi12:52:192:26:196:587:18
7:18
+0:14
35K
21.75 mi12:57:332:31:336:585:14
7:00
-0:18
23M
23.00 mi13:06:312:40:316:598:58
7:10
+0:10
24M
24.00 mi13:13:212:47:216:586:50
6:50
-0:20
40K
24.85 mi13:19:192:53:196:585:58
6:59
+0:09
25.2M
25.20 mi13:21:552:55:556:592:36
7:32
+0:33
Finish
26.22 mi13:28:393:02:396:586:44
6:36
-0:56

Checkpoints & Pacing

📈Pace Line

Pace Progression

Track your pace changes throughout the race. Dot colors mark your quickest to easiest segments, relative to your own pace.

Fastest Pace

6:36 /mi

Average Pace

6:58 /mi

Slowest Pace

7:32 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

2:52:45

95% of race

Time at Steady Pace

9:54

5% of race

Time at Slower Pace

0:00

0% of race

Average Pace: 6:58 /mi

Loading chart...
Faster pace (< avg)
Steady pace (≈ avg)
Slower pace (> avg)

🎨Heatmap

Pace Heatmap

Where you sped up and eased off relative to your own pace across the race. Colors are relative to your own range, not to other runners.

Loading...
0mi6.6mi13.1mi19.7mi26.2mi
Pace:
Faster
Steady
Slower

Click or hover over segments to see details

✨Sparklines

Checkpoint Splits with Pace Trends

Overall Pace Trend

CheckpointDistanceTime of DayTimeAvg PaceSegmentPaceTrendRank
5K
3.11 mi10:47:3821:386:5821:38
6:58
#7537
10K
6.21 mi11:09:1543:156:5821:37
6:57
#7593
15K
9.32 mi11:30:451:04:456:5721:30
6:55
#7417
20K
12.43 mi11:52:121:26:126:5621:27
6:54
#7109
Half
13.11 mi11:56:521:30:526:564:40
6:50
#7063
25K
15.53 mi12:13:311:47:316:5516:39
6:52
#6735
30K
18.64 mi12:35:252:09:256:5721:54
7:03
#6282
20M
20.00 mi12:45:012:19:016:579:36
7:04
#6072
21M
21.00 mi12:52:192:26:196:587:18
7:18
#5857
35K
21.75 mi12:57:332:31:336:585:14
7:00
#5818
23M
23.00 mi13:06:312:40:316:598:58
7:10
#5671
24M
24.00 mi13:13:212:47:216:586:50
6:50
#5526
40K
24.85 mi13:19:192:53:196:585:58
6:59
#5422
25.2M
25.20 mi13:21:552:55:556:592:36
7:32
#5364
Finish
26.22 mi13:28:393:02:396:586:44
6:36
#5245
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallFemalesF18-39Seg. OverallSeg. FemalesSeg. F18-39
5K3.11 mi3.11 mi75378178177103(Top 25%)757(Top 6%)757(Top 14%)
10K6.21 mi3.10 mi7593-56856-39856-397651(Top 27%)883(Top 7%)883(Top 16%)
15K9.32 mi3.11 mi7417+176812+44812+447103(Top 25%)757(Top 6%)757(Top 14%)
20K12.43 mi3.11 mi7109+308741+71741+716238(Top 22%)603(Top 5%)603(Top 11%)
Half13.11 mi0.68 mi7063+46732+9732+96533(Top 23%)654(Top 5%)654(Top 12%)
25K15.53 mi2.42 mi6735+328670+62670+625434(Top 19%)477(Top 4%)477(Top 9%)
30K18.64 mi3.11 mi6282+453610+60610+605026(Top 18%)453(Top 4%)453(Top 8%)
20M20.00 mi1.36 mi6072+210581+29581+294503(Top 16%)397(Top 3%)397(Top 7%)
21M21.00 mi1.00 mi5857+215545+36545+363654(Top 13%)307(Top 3%)307(Top 6%)
35K21.75 mi0.75 mi5818+39546-1546-15355(Top 19%)709(Top 6%)709(Top 13%)
23M23.00 mi1.25 mi5671+147533+13533+134674(Top 16%)575(Top 5%)575(Top 11%)
24M24.00 mi1.00 mi5526+145514+19514+193740(Top 13%)407(Top 3%)407(Top 7%)
40K24.85 mi0.85 mi5422+104503+11503+113810(Top 13%)455(Top 4%)455(Top 8%)
25.2M25.20 mi0.35 mi5364+58499+4499+43670(Top 13%)472(Top 4%)472(Top 9%)
Finish26.22 mi1.02 mi5245+119484+15484+153403(Top 12%)411(Top 3%)411(Top 8%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 25%
×21stories
+97ft-345ft

Overall

7103

Females

757

F18-39

757

5K→10K

3.1 - 6.2 mi

Top 27%
×5stories
+79ft-138ft

Overall

7651

Females

883

F18-39

883

10K→15K

6.2 - 9.3 mi

Top 25%
×3stories
+67ft-78ft

Overall

7103

Females

757

F18-39

757

15K→20K

9.3 - 12.4 mi

Top 22%
×5stories
+106ft-86ft

Overall

6238

Females

603

F18-39

603

20K→Half

12.4 - 13.1 mi

Top 23%
×2stories
+19ft-37ft

Overall

6533

Females

654

F18-39

654

Half→25K

13.1 - 15.5 mi

Top 19%
×4stories
+66ft-88ft

Overall

5434

Females

477

F18-39

477

25K→30K

15.5 - 18.6 mi

Top 18%
×9stories
+181ft-148ft

Overall

5026

Females

453

F18-39

453

30K→20M

18.6 - 20.0 mi

Top 16%
×5stories
+64ft-50ft

Overall

4503

Females

397

F18-39

397

20M→21M

20.0 - 21.0 mi

Top 13%
×8stories
+106ft-24ft

Overall

3654

Females

307

F18-39

307

21M→35K

21.0 - 21.8 mi

Top 19%
×7stories
+17ft-86ft

Overall

5355

Females

709

F18-39

709

35K→23M

21.8 - 23.0 mi

Top 16%
×5stories
+23ft-63ft

Overall

4674

Females

575

F18-39

575

23M→24M

23.0 - 24.0 mi

Top 13%
×6stories
+12ft-82ft

Overall

3740

Females

407

F18-39

407

24M→40K

24.0 - 24.9 mi

Top 13%
×1story
+6ft-20ft

Overall

3810

Females

455

F18-39

455

40K→25.2M

24.9 - 25.2 mi

Top 13%
×1story
+13ft-16ft

Overall

3670

Females

472

F18-39

472

25.2M→Finish

25.2 - 26.2 mi

Top 12%
×2stories
+22ft-21ft

Overall

3403

Females

411

F18-39

411

Passing Analysis

Category:
Athletes Passed
2669
Passed By
377
Net Change
+2292
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#7537
5K → 10K179235-56#7537#7593
10K → 15K22852+176#7593#7417
15K → 20K32315+308#7417#7109
20K → Half504+46#7109#7063
Half → 25K3302+328#7063#6735
25K → 30K46512+453#6735#6282
30K → 20M2122+210#6282#6072
20M → 21M2205+215#6072#5857
21M → 35K5819+39#5857#5818
35K → 23M15811+147#5818#5671
23M → 24M1505+145#5671#5526
24M → 40K1117+104#5526#5422
40K → 25.2M580+58#5422#5364
25.2M → Finish1278+119#5364#5245
TOTALS2669377+2292
📊

Passing Visuals

Category:
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🔥Passing Intensity

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🔄Passing Circle

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🌊Position Flow

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🏃Race Lanes

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Public Race Data

Boston Athletic Association

Boston Athletic Association

Mika Timing

Mika Timing