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BOSTON MARATHON 2025

Anson Lam

Bib: 4251•M

CA

0:00
0:00
/ mi
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Overall
#0 / 28404
Top 12%
Gender (Male)
#0 / 16105
Top 20%
Division (M18-39)
#0 / 5642
Top 43%
Race Day Weather
50°/40°F
broken clouds

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
20:05
Rank: #3578
Start → 5K
6:28/mi
20:05 split
10K· 6.21 mi
40:04
Rank: #3394 (+184)
5K → 10K
6:26/mi
19:59 split
15K· 9.32 mi
1:00:06
Rank: #3310 (+84)
10K → 15K
6:27/mi
20:02 split
20K· 12.43 mi
1:20:37
Rank: #3416 (-106)
15K → 20K
6:36/mi
20:31 split
Half· 13.11 mi
1:25:05
Rank: #3436 (-20)
20K → Half
6:33/mi
4:28 split
25K· 15.53 mi
1:41:15
Rank: #3507 (-71)
Half → 25K
6:40/mi
16:10 split
30K· 18.64 mi
2:02:31
Rank: #3477 (+30)
25K → 30K
6:51/mi
21:16 split
20M
2:11:48
Rank: #3409 (+68)
30K → 20M
6:50/mi
9:17 split
21M
2:19:06
Rank: #3389 (+20)
20M → 21M
7:18/mi
7:18 split
35K· 21.75 mi
2:24:17
Rank: #3409 (-20)
21M → 35K
6:56/mi
5:11 split
23M
2:33:07
Rank: #3396 (+13)
35K → 23M
7:03/mi
8:50 split
24M
2:39:47
Rank: #3324 (+72)
23M → 24M
6:40/mi
6:40 split
40K· 24.85 mi
2:45:59
Rank: #3374 (-50)
24M → 40K
7:15/mi
6:12 split
25.2M
2:48:40
Rank: #3386 (-12)
40K → 25.2M
7:47/mi
2:41 split
Finish· 26.22 mi
2:55:35
Rank: #3374 (+12)
25.2M → Finish
6:47/mi
6:55 split

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:25:05
Pace6:29 /mi
2nd Half
Distance13.11 mi
Time1:30:30
Pace6:54 /mi
📊Positive Split: 6.4% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:22:4520:056:2820:05
6:28
-
10K
6.21 mi10:42:4440:046:2719:59
6:26
-0:02
15K
9.32 mi11:02:461:00:066:2720:02
6:27
+0:01
20K
12.43 mi11:23:171:20:376:2920:31
6:36
+0:09
Half
13.11 mi11:27:451:25:056:294:28
6:33
-0:03
25K
15.53 mi11:43:551:41:156:3116:10
6:40
+0:07
30K
18.64 mi12:05:112:02:316:3421:16
6:51
+0:11
20M
20.00 mi12:14:282:11:486:359:17
6:50
-0:01
21M
21.00 mi12:21:462:19:066:377:18
7:18
+0:28
35K
21.75 mi12:26:572:24:176:385:11
6:56
-0:22
23M
23.00 mi12:35:472:33:076:398:50
7:03
+0:07
24M
24.00 mi12:42:272:39:476:396:40
6:40
-0:23
40K
24.85 mi12:48:392:45:596:416:12
7:15
+0:35
25.2M
25.20 mi12:51:202:48:406:422:41
7:47
+0:32
Finish
26.22 mi12:58:152:55:356:426:55
6:47
-1:00

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

6:26 /mi

Average Pace

6:42 /mi

Slowest Pace

7:47 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

1:25:05

48% of race

Time at Steady Pace

1:05:29

37% of race

Time at Slower Pace

25:01

14% of race

Average Pace: 6:42 /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 mi10:22:4520:056:2820:05
6:28
#3578
10K
6.21 mi10:42:4440:046:2719:59
6:26
#3394
15K
9.32 mi11:02:461:00:066:2720:02
6:27
#3310
20K
12.43 mi11:23:171:20:376:2920:31
6:36
#3416
Half
13.11 mi11:27:451:25:056:294:28
6:33
#3436
25K
15.53 mi11:43:551:41:156:3116:10
6:40
#3507
30K
18.64 mi12:05:112:02:316:3421:16
6:51
#3477
20M
20.00 mi12:14:282:11:486:359:17
6:50
#3409
21M
21.00 mi12:21:462:19:066:377:18
7:18
#3389
35K
21.75 mi12:26:572:24:176:385:11
6:56
#3409
23M
23.00 mi12:35:472:33:076:398:50
7:03
#3396
24M
24.00 mi12:42:272:39:476:396:40
6:40
#3324
40K
24.85 mi12:48:392:45:596:416:12
7:15
#3374
25.2M
25.20 mi12:51:202:48:406:422:41
7:47
#3386
Finish
26.22 mi12:58:152:55:356:426:55
6:47
#3374
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM18-39Seg. OverallSeg. MalesSeg. M18-39
5K3.11 mi3.11 mi3578339933993247(Top 11%)3087(Top 19%)3087(Top 55%)
10K6.21 mi3.10 mi3394+1843223+1763223+1763263(Top 11%)3101(Top 19%)3101(Top 55%)
15K9.32 mi3.11 mi3310+843145+783145+783247(Top 11%)3087(Top 19%)3087(Top 55%)
20K12.43 mi3.11 mi3416-1063241-963241-963727(Top 13%)3520(Top 22%)3520(Top 62%)
Half13.11 mi0.68 mi3436-203258-173258-174023(Top 14%)3787(Top 24%)3787(Top 67%)
25K15.53 mi2.42 mi3507-713320-623320-623904(Top 14%)3651(Top 23%)3651(Top 65%)
30K18.64 mi3.11 mi3477+303290+303290+303717(Top 13%)3439(Top 21%)3439(Top 61%)
20M20.00 mi1.36 mi3409+683223+673223+673136(Top 11%)2912(Top 18%)2912(Top 52%)
21M21.00 mi1.00 mi3389+203203+203203+203633(Top 13%)3322(Top 21%)3322(Top 59%)
35K21.75 mi0.75 mi3409-203218-153218-154911(Top 17%)4323(Top 27%)4323(Top 77%)
23M23.00 mi1.25 mi3396+133199+193199+194081(Top 14%)3640(Top 23%)3640(Top 65%)
24M24.00 mi1.00 mi3324+723128+713128+712813(Top 10%)2580(Top 16%)2580(Top 46%)
40K24.85 mi0.85 mi3374-503171-433171-435361(Top 19%)4462(Top 28%)4462(Top 79%)
25.2M25.20 mi0.35 mi3386-123177-63177-64765(Top 17%)3963(Top 25%)3963(Top 70%)
Finish26.22 mi1.02 mi3374+123159+183159+184429(Top 16%)3745(Top 23%)3745(Top 66%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 11%
×21stories
+97ft-345ft

Overall

3247

Males

3087

M18-39

3087

5K→10K

3.1 - 6.2 mi

Top 11%
×5stories
+79ft-138ft

Overall

3263

Males

3101

M18-39

3101

10K→15K

6.2 - 9.3 mi

Top 11%
×3stories
+67ft-78ft

Overall

3247

Males

3087

M18-39

3087

15K→20K

9.3 - 12.4 mi

Top 13%
×5stories
+106ft-86ft

Overall

3727

Males

3520

M18-39

3520

20K→Half

12.4 - 13.1 mi

Top 14%
×2stories
+19ft-37ft

Overall

4023

Males

3787

M18-39

3787

Half→25K

13.1 - 15.5 mi

Top 14%
×4stories
+66ft-88ft

Overall

3904

Males

3651

M18-39

3651

25K→30K

15.5 - 18.6 mi

Top 13%
×9stories
+181ft-148ft

Overall

3717

Males

3439

M18-39

3439

30K→20M

18.6 - 20.0 mi

Top 11%
×5stories
+64ft-50ft

Overall

3136

Males

2912

M18-39

2912

20M→21M

20.0 - 21.0 mi

Top 13%
×8stories
+106ft-24ft

Overall

3633

Males

3322

M18-39

3322

21M→35K

21.0 - 21.8 mi

Top 17%
×7stories
+17ft-86ft

Overall

4911

Males

4323

M18-39

4323

35K→23M

21.8 - 23.0 mi

Top 14%
×5stories
+23ft-63ft

Overall

4081

Males

3640

M18-39

3640

23M→24M

23.0 - 24.0 mi

Top 10%
×6stories
+12ft-82ft

Overall

2813

Males

2580

M18-39

2580

24M→40K

24.0 - 24.9 mi

Top 19%
×1story
+6ft-20ft

Overall

5361

Males

4462

M18-39

4462

40K→25.2M

24.9 - 25.2 mi

Top 17%
×1story
+13ft-16ft

Overall

4765

Males

3963

M18-39

3963

25.2M→Finish

25.2 - 26.2 mi

Top 16%
×2stories
+22ft-21ft

Overall

4429

Males

3745

M18-39

3745

Passing Analysis

Category:
Athletes Passed
1064
Passed By
860
Net Change
+204
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#3578
5K → 10K24864+184#3578#3394
10K → 15K13955+84#3394#3310
15K → 20K64170-106#3310#3416
20K → Half929-20#3416#3436
Half → 25K49120-71#3436#3507
25K → 30K12494+30#3507#3477
30K → 20M9527+68#3477#3409
20M → 21M6444+20#3409#3389
21M → 35K2646-20#3389#3409
35K → 23M6653+13#3409#3396
23M → 24M8715+72#3396#3324
24M → 40K2676-50#3324#3374
40K → 25.2M1527-12#3374#3386
25.2M → Finish5240+12#3386#3374
TOTALS1064860+204
📊

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