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BOSTON MARATHON 2025

Isabel Siu-Zmuidzinas

BC

Bib: 11825 F

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

⏱️ Race Timeline

Ribbon color based on
FasterSteadySlower· vs. your average pace
Start
0:00
Race begins
469 ft elev
5K· 3.11 mi
7:36/mi
23:36
↑ 97↓ 3451.5%
220 ft elev
10K· 6.21 mi
7:42/mi
47:31
↑ 79↓ 1380.4%
157 ft elev
15K· 9.32 mi
7:47/mi
1:11:41
↑ 67↓ 78
146 ft elev
20K· 12.43 mi
8:04/mi
1:36:45
↑ 106↓ 860.1%
165 ft elev
Half· 13.11 mi
8:07/mi
1:42:17
↑ 19↓ 370.5%
148 ft elev
25K· 15.53 mi
9:04/mi
2:04:15
↑ 66↓ 880.2%
127 ft elev
30K· 18.64 mi
10:22/mi
2:36:29
↑ 181↓ 1480.2%
138 ft elev
20M
9:50/mi
2:49:51
↑ 64↓ 500.2%
148 ft elev
21M
11:03/mi
3:00:54
↑ 106↓ 241.6%
227 ft elev
35K· 21.75 mi
10:43/mi
3:08:55
↑ 17↓ 861.7%
156 ft elev
23M
10:57/mi
3:22:37
↑ 23↓ 630.6%
116 ft elev
24M
10:34/mi
3:33:11
↓ 821.3%
34 ft elev
40K· 24.85 mi
11:39/mi
3:43:09
↓ 200.3%
20 ft elev
25.2M
10:52/mi
3:46:54
↑ 13↓ 160.2%
18 ft elev
Finish· 26.22 mi
9:19/mi
3:56:24
↑ 22↓ 21
17 ft elev
Course Elevation
7–469 ft
≈
×2stacked redwood trees
•▲ 890 ft climb · ▼ 1342 ft descent

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:42:17
Pace7:48 /mi
2nd Half
Distance13.11 mi
Time2:14:07
Pace10:14 /mi
📊Positive Split: 31.1% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:52:5823:367:3623:36
7:36
-
10K
6.21 mi11:16:5347:317:3923:55
7:42
+0:06
15K
9.32 mi11:41:031:11:417:4124:10
7:47
+0:05
20K
12.43 mi12:06:071:36:457:4725:04
8:04
+0:17
Half
13.11 mi12:11:391:42:177:485:32
8:07
+0:03
25K
15.53 mi12:33:372:04:158:0021:58
9:04
+0:57
30K
18.64 mi13:05:512:36:298:2432:14
10:22
+1:18
20M
20.00 mi13:19:132:49:518:3013:22
9:50
-0:32
21M
21.00 mi13:30:163:00:548:3711:03
11:03
+1:13
35K
21.75 mi13:38:173:08:558:418:01
10:43
-0:20
23M
23.00 mi13:51:593:22:378:4913:42
10:57
+0:14
24M
24.00 mi14:02:333:33:118:5310:34
10:34
-0:23
40K
24.85 mi14:12:313:43:098:599:58
11:39
+1:05
25.2M
25.20 mi14:16:163:46:549:003:45
10:52
-0:47
Finish
26.22 mi14:25:463:56:249:019:30
9:19
-1:33

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

7:36 /mi

Average Pace

9:01 /mi

Slowest Pace

11:39 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

2:04:15

53% of race

Time at Steady Pace

55:06

23% of race

Time at Slower Pace

57:03

24% of race

Average Pace: 9:01 /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 mi10:52:5823:367:3623:36
7:36
#13104
10K
6.21 mi11:16:5347:317:3923:55
7:42
#13480
15K
9.32 mi11:41:031:11:417:4124:10
7:47
#13679
20K
12.43 mi12:06:071:36:457:4725:04
8:04
#14133
Half
13.11 mi12:11:391:42:177:485:32
8:07
#14269
25K
15.53 mi12:33:372:04:158:0021:58
9:04
#15532
30K
18.64 mi13:05:512:36:298:2432:14
10:22
#17437
20M
20.00 mi13:19:132:49:518:3013:22
9:50
#17732
21M
21.00 mi13:30:163:00:548:3711:03
11:03
#18096
35K
21.75 mi13:38:173:08:558:418:01
10:43
#18462
23M
23.00 mi13:51:593:22:378:4913:42
10:57
#18929
24M
24.00 mi14:02:333:33:118:5310:34
10:34
#19210
40K
24.85 mi14:12:313:43:098:599:58
11:39
#19557
25.2M
25.20 mi14:16:163:46:549:003:45
10:52
#19587
Finish
26.22 mi14:25:463:56:249:019:30
9:19
#19639
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallFemalesF18-39Seg. OverallSeg. FemalesSeg. F18-39
5K3.11 mi3.11 mi131043383338314211(Top 50%)4150(Top 34%)4150(Top 76%)
10K6.21 mi3.10 mi13480-3763641-2583641-25813908(Top 49%)3909(Top 32%)3909(Top 71%)
15K9.32 mi3.11 mi13679-1993785-1443785-14414211(Top 50%)4150(Top 34%)4150(Top 76%)
20K12.43 mi3.11 mi14133-4544083-2984083-29815429(Top 54%)4881(Top 40%)4881(Top 89%)
Half13.11 mi0.68 mi14269-1364163-804163-8016775(Top 59%)5650(Top 46%)5650(Top 103%)
25K15.53 mi2.42 mi15532-12634908-7454908-74520182(Top 71%)7636(Top 62%)7636(Top 140%)
30K18.64 mi3.11 mi17437-19056078-11706078-117022645(Top 80%)9129(Top 75%)9129(Top 167%)
20M20.00 mi1.36 mi17732-2956280-2026280-20220412(Top 72%)8024(Top 66%)8024(Top 147%)
21M21.00 mi1.00 mi18096-3646489-2096489-20921541(Top 76%)8731(Top 71%)8731(Top 160%)
35K21.75 mi0.75 mi18462-3666715-2266715-22623622(Top 83%)9858(Top 81%)9858(Top 180%)
23M23.00 mi1.25 mi18929-4677008-2937008-29323092(Top 81%)9648(Top 79%)9648(Top 176%)
24M24.00 mi1.00 mi19210-2817192-1847192-18422997(Top 81%)9633(Top 79%)9633(Top 176%)
40K24.85 mi0.85 mi19557-3477412-2207412-22024415(Top 86%)10378(Top 85%)10378(Top 190%)
25.2M25.20 mi0.35 mi19587-307449-377449-3720280(Top 71%)8300(Top 68%)8300(Top 152%)
Finish26.22 mi1.02 mi19639-527486-377486-3720485(Top 72%)8383(Top 69%)8383(Top 153%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 50%
×21story building
+97ft-345ft

Overall

14211

Females

4150

F18-39

4150

5K→10K

3.1 - 6.2 mi

Top 49%
×5story building
+79ft-138ft

Overall

13908

Females

3909

F18-39

3909

10K→15K

6.2 - 9.3 mi

Top 50%
×3story building
+67ft-78ft

Overall

14211

Females

4150

F18-39

4150

15K→20K

9.3 - 12.4 mi

Top 54%
×5story building
+106ft-86ft

Overall

15429

Females

4881

F18-39

4881

20K→Half

12.4 - 13.1 mi

Top 59%
×2story building
+19ft-37ft

Overall

16775

Females

5650

F18-39

5650

Half→25K

13.1 - 15.5 mi

Top 71%
×4story building
+66ft-88ft

Overall

20182

Females

7636

F18-39

7636

25K→30K

15.5 - 18.6 mi

Top 80%
×9story building
+181ft-148ft

Overall

22645

Females

9129

F18-39

9129

30K→20M

18.6 - 20.0 mi

Top 72%
×5story building
+64ft-50ft

Overall

20412

Females

8024

F18-39

8024

20M→21M

20.0 - 21.0 mi

Top 76%
×8story building
+106ft-24ft

Overall

21541

Females

8731

F18-39

8731

21M→35K

21.0 - 21.8 mi

Top 83%
×7story building
+17ft-86ft

Overall

23622

Females

9858

F18-39

9858

35K→23M

21.8 - 23.0 mi

Top 81%
×5story building
+23ft-63ft

Overall

23092

Females

9648

F18-39

9648

23M→24M

23.0 - 24.0 mi

Top 81%
×6story building
+12ft-82ft

Overall

22997

Females

9633

F18-39

9633

24M→40K

24.0 - 24.9 mi

Top 86%
×1story
+6ft-20ft

Overall

24415

Females

10378

F18-39

10378

40K→25.2M

24.9 - 25.2 mi

Top 71%
×1story
+13ft-16ft

Overall

20280

Females

8300

F18-39

8300

25.2M→Finish

25.2 - 26.2 mi

Top 72%
×2story building
+22ft-21ft

Overall

20485

Females

8383

F18-39

8383

Passing Analysis

Category:
Athletes Passed
657
Passed By
7192
Net Change
-6535
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#13104
5K → 10K149525-376#13104#13480
10K → 15K147346-199#13480#13679
15K → 20K105559-454#13679#14133
20K → Half1137-136#14133#14269
Half → 25K201283-1263#14269#15532
25K → 30K141919-1905#15532#17437
30K → 20M54349-295#17437#17732
20M → 21M23387-364#17732#18096
21M → 35K13379-366#18096#18462
35K → 23M33500-467#18462#18929
23M → 24M17298-281#18929#19210
24M → 40K17364-347#19210#19557
40K → 25.2M2555-30#19557#19587
25.2M → Finish3991-52#19587#19639
TOTALS6577192-6535
📊

Passing Visuals

Category:
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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