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BOSTON MARATHON 2025

Lee-Kai Sun

Bib: 4370•M

PA

0:00
0:00
/ mi
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Overall
#0 / 28404
Top 41%
Gender (Male)
#0 / 16105
Division (M18-39)
#0 / 5642
Race Day Weather
50°/40°F
broken clouds

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
20:06
Rank: #3626
Start → 5K
20:06 | 6:28/mi
10K· 6.21 mi
40:13
Rank: #3576 (+50)
5K → 10K
20:07 | 6:28/mi
15K· 9.32 mi
1:00:29
Rank: #3621 (-45)
10K → 15K
20:16 | 6:31/mi
20K· 12.43 mi
1:21:44
Rank: #3999 (-378)
15K → 20K
21:15 | 6:50/mi
Half· 13.11 mi
1:26:24
Rank: #4089 (-90)
20K → Half
4:40 | 6:50/mi
25K· 15.53 mi
1:45:54
Rank: #5876 (-1787)
Half → 25K
19:30 | 8:03/mi
30K· 18.64 mi
2:12:11
Rank: #7288 (-1412)
25K → 30K
26:17 | 8:28/mi
20M
2:25:45
Rank: #8439 (-1151)
30K → 20M
13:34 | 9:59/mi
21M
2:36:28
Rank: #9411 (-972)
20M → 21M
10:43 | 10:43/mi
35K· 21.75 mi
2:43:26
Rank: #9871 (-460)
21M → 35K
6:58 | 9:19/mi
23M
2:54:44
Rank: #10323 (-452)
35K → 23M
11:18 | 9:02/mi
24M
3:04:03
Rank: #10764 (-441)
23M → 24M
9:19 | 9:19/mi
40K· 24.85 mi
3:12:05
Rank: #11086 (-322)
24M → 40K
8:02 | 9:24/mi
25.2M
3:15:47
Rank: #11270 (-184)
40K → 25.2M
3:42 | 10:44/mi
Finish· 26.22 mi
3:25:05
Rank: #11705 (-435)
25.2M → Finish
9:18 | 9:08/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:26:24
Pace6:35 /mi
2nd Half
Distance13.11 mi
Time1:58:41
Pace9:03 /mi
📊Positive Split: 37.4% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:22:2020:066:2820:06
6:28
-
10K
6.21 mi10:42:2740:136:2820:07
6:28
0:00
15K
9.32 mi11:02:431:00:296:2920:16
6:31
+0:03
20K
12.43 mi11:23:581:21:446:3521:15
6:50
+0:19
Half
13.11 mi11:28:381:26:246:354:40
6:50
0:00
25K
15.53 mi11:48:081:45:546:4919:30
8:03
+1:13
30K
18.64 mi12:14:252:12:117:0526:17
8:28
+0:25
20M
20.00 mi12:27:592:25:457:1713:34
9:59
+1:31
21M
21.00 mi12:38:422:36:287:2710:43
10:43
+0:44
35K
21.75 mi12:45:402:43:267:316:58
9:19
-1:24
23M
23.00 mi12:56:582:54:447:3611:18
9:02
-0:17
24M
24.00 mi13:06:173:04:037:409:19
9:19
+0:17
40K
24.85 mi13:14:193:12:057:448:02
9:24
+0:05
25.2M
25.20 mi13:18:013:15:477:463:42
10:44
+1:20
Finish
26.22 mi13:27:193:25:057:509:18
9:08
-1:36

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

6:28 /mi

Average Pace

7:50 /mi

Slowest Pace

10:44 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

1:45:54

52% of race

Time at Steady Pace

1:11:12

35% of race

Time at Slower Pace

27:59

14% of race

Average Pace: 7:49 /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 mi10:22:2020:066:2820:06
6:28
#3626
10K
6.21 mi10:42:2740:136:2820:07
6:28
#3576
15K
9.32 mi11:02:431:00:296:2920:16
6:31
#3621
20K
12.43 mi11:23:581:21:446:3521:15
6:50
#3999
Half
13.11 mi11:28:381:26:246:354:40
6:50
#4089
25K
15.53 mi11:48:081:45:546:4919:30
8:03
#5876
30K
18.64 mi12:14:252:12:117:0526:17
8:28
#7288
20M
20.00 mi12:27:592:25:457:1713:34
9:59
#8439
21M
21.00 mi12:38:422:36:287:2710:43
10:43
#9411
35K
21.75 mi12:45:402:43:267:316:58
9:19
#9871
23M
23.00 mi12:56:582:54:447:3611:18
9:02
#10323
24M
24.00 mi13:06:173:04:037:409:19
9:19
#10764
40K
24.85 mi13:14:193:12:057:448:02
9:24
#11086
25.2M
25.20 mi13:18:013:15:477:463:42
10:44
#11270
Finish
26.22 mi13:27:193:25:057:509:18
9:08
#11705
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM18-39Seg. OverallSeg. MalesSeg. M18-39
5K3.11 mi3.11 mi3626344134413718(Top 13%)3511(Top 22%)3511(Top 62%)
10K6.21 mi3.10 mi3576+503392+493392+493563(Top 13%)3374(Top 21%)3374(Top 60%)
15K9.32 mi3.11 mi3621-453428-363428-363718(Top 13%)3511(Top 22%)3511(Top 62%)
20K12.43 mi3.11 mi3999-3783766-3383766-3385705(Top 20%)5203(Top 32%)5203(Top 92%)
Half13.11 mi0.68 mi4089-903850-843850-846519(Top 23%)5859(Top 36%)5859(Top 104%)
25K15.53 mi2.42 mi5876-17875360-15105360-151014203(Top 50%)9847(Top 61%)9847(Top 175%)
30K18.64 mi3.11 mi7288-14126415-10556415-105514494(Top 51%)9823(Top 61%)9823(Top 174%)
20M20.00 mi1.36 mi8439-11517112-6977112-69720868(Top 73%)12522(Top 78%)12522(Top 222%)
21M21.00 mi1.00 mi9411-9727627-5157627-51520623(Top 73%)12307(Top 76%)12307(Top 218%)
35K21.75 mi0.75 mi9871-4607851-2247851-22419588(Top 69%)11765(Top 73%)11765(Top 209%)
23M23.00 mi1.25 mi10323-4528024-1738024-17316385(Top 58%)10227(Top 64%)10227(Top 181%)
24M24.00 mi1.00 mi10764-4418208-1848208-18418861(Top 66%)11334(Top 70%)11334(Top 201%)
40K24.85 mi0.85 mi11086-3228323-1158323-11518229(Top 64%)10935(Top 68%)10935(Top 194%)
25.2M25.20 mi0.35 mi11270-1848387-648387-6419756(Top 70%)11654(Top 72%)11654(Top 207%)
Finish26.22 mi1.02 mi11705-4358565-1788565-17819592(Top 69%)11617(Top 72%)11617(Top 206%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 13%
×21stories
+97ft-345ft

Overall

3718

Males

3511

M18-39

3511

5K→10K

3.1 - 6.2 mi

Top 13%
×5stories
+79ft-138ft

Overall

3563

Males

3374

M18-39

3374

10K→15K

6.2 - 9.3 mi

Top 13%
×3stories
+67ft-78ft

Overall

3718

Males

3511

M18-39

3511

15K→20K

9.3 - 12.4 mi

Top 20%
×5stories
+106ft-86ft

Overall

5705

Males

5203

M18-39

5203

20K→Half

12.4 - 13.1 mi

Top 23%
×2stories
+19ft-37ft

Overall

6519

Males

5859

M18-39

5859

Half→25K

13.1 - 15.5 mi

Top 50%
×4stories
+66ft-88ft

Overall

14203

Males

9847

M18-39

9847

25K→30K

15.5 - 18.6 mi

Top 51%
×9stories
+181ft-148ft

Overall

14494

Males

9823

M18-39

9823

30K→20M

18.6 - 20.0 mi

Top 73%
×5stories
+64ft-50ft

Overall

20868

Males

12522

M18-39

12522

20M→21M

20.0 - 21.0 mi

Top 73%
×8stories
+106ft-24ft

Overall

20623

Males

12307

M18-39

12307

21M→35K

21.0 - 21.8 mi

Top 69%
×7stories
+17ft-86ft

Overall

19588

Males

11765

M18-39

11765

35K→23M

21.8 - 23.0 mi

Top 58%
×5stories
+23ft-63ft

Overall

16385

Males

10227

M18-39

10227

23M→24M

23.0 - 24.0 mi

Top 66%
×6stories
+12ft-82ft

Overall

18861

Males

11334

M18-39

11334

24M→40K

24.0 - 24.9 mi

Top 64%
×1story
+6ft-20ft

Overall

18229

Males

10935

M18-39

10935

40K→25.2M

24.9 - 25.2 mi

Top 70%
×1story
+13ft-16ft

Overall

19756

Males

11654

M18-39

11654

25.2M→Finish

25.2 - 26.2 mi

Top 69%
×2stories
+22ft-21ft

Overall

19592

Males

11617

M18-39

11617

Passing Analysis

Category:
Athletes Passed
410
Passed By
8487
Net Change
-8079
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#3626
5K → 10K161111+50#3626#3576
10K → 15K89134-45#3576#3621
15K → 20K26404-378#3621#3999
20K → Half393-90#3999#4089
Half → 25K41791-1787#4089#5876
25K → 30K151427-1412#5876#7288
30K → 20M71158-1151#7288#8439
20M → 21M6978-972#8439#9411
21M → 35K13473-460#9411#9871
35K → 23M31481-452#9871#10323
23M → 24M14455-441#10323#10764
24M → 40K18340-322#10764#11086
40K → 25.2M5189-184#11086#11270
25.2M → Finish18453-435#11270#11705
TOTALS4108487-8079
📊

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