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BOSTON MARATHON 2025

Lai Chong Yu

Bib: 29161•F

0:00
0:00
/ mi
Masters
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Overall
#0 / 28404
Gender (Female)
#0 / 12228
Masters (Masters Women)
#0 / 6759
Division (F50-54)
#0 / 1303
Race Day Weather
50°/40°F
broken clouds

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
35:34
Rank: #27976
Start → 5K
35:34 | 11:27/mi
10K· 6.21 mi
1:11:57
Rank: #27876 (+100)
5K → 10K
36:23 | 11:43/mi
15K· 9.32 mi
1:50:07
Rank: #27889 (-13)
10K → 15K
38:10 | 12:17/mi
20K· 12.43 mi
2:29:40
Rank: #27852 (+37)
15K → 20K
39:33 | 12:44/mi
Half· 13.11 mi
2:38:28
Rank: #27865 (-13)
20K → Half
8:48 | 12:54/mi
25K· 15.53 mi
3:10:57
Rank: #27823 (+42)
Half → 25K
32:29 | 13:24/mi
30K· 18.64 mi
3:53:32
Rank: #27744 (+79)
25K → 30K
42:35 | 13:42/mi
20M
4:11:51
Rank: #27688 (+56)
30K → 20M
18:19 | 13:29/mi
21M
4:25:57
Rank: #27639 (+49)
20M → 21M
14:06 | 14:06/mi
35K· 21.75 mi
4:35:52
Rank: #27639
21M → 35K
9:55 | 13:15/mi
23M
4:54:53
Rank: #27679 (-40)
35K → 23M
19:01 | 15:11/mi
24M
5:07:43
Rank: #27658 (+21)
23M → 24M
12:50 | 12:50/mi
40K· 24.85 mi
5:18:31
Rank: #27619 (+39)
24M → 40K
10:48 | 12:38/mi
25.2M
5:23:35
Rank: #27615 (+4)
40K → 25.2M
5:04 | 14:42/mi
Finish· 26.22 mi
5:36:26
Rank: #27623 (-8)
25.2M → Finish
12:51 | 12:37/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time2:38:28
Pace12:05 /mi
2nd Half
Distance13.11 mi
Time2:57:58
Pace13:35 /mi
📊Positive Split: 12.3% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi11:57:2235:3411:2735:34
11:27
-
10K
6.21 mi12:33:451:11:5711:3536:23
11:43
+0:16
15K
9.32 mi13:11:551:50:0711:4938:10
12:17
+0:34
20K
12.43 mi13:51:282:29:4012:0339:33
12:44
+0:27
Half
13.11 mi14:00:162:38:2812:058:48
12:54
+0:10
25K
15.53 mi14:32:453:10:5712:1832:29
13:24
+0:30
30K
18.64 mi15:15:203:53:3212:3242:35
13:42
+0:18
20M
20.00 mi15:33:394:11:5112:3618:19
13:29
-0:13
21M
21.00 mi15:47:454:25:5712:4014:06
14:06
+0:37
35K
21.75 mi15:57:404:35:5212:419:55
13:15
-0:51
23M
23.00 mi16:16:414:54:5312:4919:01
15:11
+1:56
24M
24.00 mi16:29:315:07:4312:4912:50
12:50
-2:21
40K
24.85 mi16:40:195:18:3112:4910:48
12:38
-0:12
25.2M
25.20 mi16:45:235:23:3512:505:04
14:42
+2:04
Finish
26.22 mi16:58:145:36:2612:5012:51
12:37
-2:05

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

11:27 /mi

Average Pace

12:50 /mi

Slowest Pace

15:11 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

1:50:07

33% of race

Time at Steady Pace

1:34:45

28% of race

Time at Slower Pace

2:11:34

39% of race

Average Pace: 12:50 /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 mi11:57:2235:3411:2735:34
11:27
#27976
10K
6.21 mi12:33:451:11:5711:3536:23
11:43
#27876
15K
9.32 mi13:11:551:50:0711:4938:10
12:17
#27889
20K
12.43 mi13:51:282:29:4012:0339:33
12:44
#27852
Half
13.11 mi14:00:162:38:2812:058:48
12:54
#27865
25K
15.53 mi14:32:453:10:5712:1832:29
13:24
#27823
30K
18.64 mi15:15:203:53:3212:3242:35
13:42
#27744
20M
20.00 mi15:33:394:11:5112:3618:19
13:29
#27688
21M
21.00 mi15:47:454:25:5712:4014:06
14:06
#27639
35K
21.75 mi15:57:404:35:5212:419:55
13:15
#27639
23M
23.00 mi16:16:414:54:5312:4919:01
15:11
#27679
24M
24.00 mi16:29:315:07:4312:4912:50
12:50
#27658
40K
24.85 mi16:40:195:18:3112:4910:48
12:38
#27619
25.2M
25.20 mi16:45:235:23:3512:505:04
14:42
#27615
Finish
26.22 mi16:58:145:36:2612:5012:51
12:37
#27623
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallFemalesF50-54Seg. OverallSeg. FemalesSeg. F50-54
5K3.11 mi3.11 mi27976119481194827813(Top 98%)11868(Top 97%)11868(Top 911%)
10K6.21 mi3.10 mi27876+10011875+7311875+7327763(Top 98%)11818(Top 97%)11818(Top 907%)
15K9.32 mi3.11 mi27889-1311901-2611901-2627813(Top 98%)11868(Top 97%)11868(Top 911%)
20K12.43 mi3.11 mi27852+3711883+1811883+1827672(Top 97%)11804(Top 97%)11804(Top 906%)
Half13.11 mi0.68 mi27865-1311889-611889-627954(Top 98%)11978(Top 98%)11978(Top 919%)
25K15.53 mi2.42 mi27823+4211870+1911870+1927565(Top 97%)11753(Top 96%)11753(Top 902%)
30K18.64 mi3.11 mi27744+7911835+3511835+3527292(Top 96%)11653(Top 95%)11653(Top 894%)
20M20.00 mi1.36 mi27688+5611817+1811817+1826876(Top 95%)11492(Top 94%)11492(Top 882%)
21M21.00 mi1.00 mi27639+4911795+2211795+2226327(Top 93%)11227(Top 92%)11227(Top 862%)
35K21.75 mi0.75 mi2763911796-111796-127172(Top 96%)11677(Top 95%)11677(Top 896%)
23M23.00 mi1.25 mi27679-4011821-2511821-2527982(Top 99%)12084(Top 99%)12084(Top 927%)
24M24.00 mi1.00 mi27658+2111818+311818+326667(Top 94%)11460(Top 94%)11460(Top 880%)
40K24.85 mi0.85 mi27619+3911802+1611802+1625832(Top 91%)11058(Top 90%)11058(Top 849%)
25.2M25.20 mi0.35 mi27615+411803-111803-126878(Top 95%)11606(Top 95%)11606(Top 891%)
Finish26.22 mi1.02 mi27623-811816-1311816-1327359(Top 96%)11801(Top 97%)11801(Top 906%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 98%
×21stories
+97ft-345ft

Overall

27813

Females

11868

F50-54

11868

5K→10K

3.1 - 6.2 mi

Top 98%
×5stories
+79ft-138ft

Overall

27763

Females

11818

F50-54

11818

10K→15K

6.2 - 9.3 mi

Top 98%
×3stories
+67ft-78ft

Overall

27813

Females

11868

F50-54

11868

15K→20K

9.3 - 12.4 mi

Top 97%
×5stories
+106ft-86ft

Overall

27672

Females

11804

F50-54

11804

20K→Half

12.4 - 13.1 mi

Top 98%
×2stories
+19ft-37ft

Overall

27954

Females

11978

F50-54

11978

Half→25K

13.1 - 15.5 mi

Top 97%
×4stories
+66ft-88ft

Overall

27565

Females

11753

F50-54

11753

25K→30K

15.5 - 18.6 mi

Top 96%
×9stories
+181ft-148ft

Overall

27292

Females

11653

F50-54

11653

30K→20M

18.6 - 20.0 mi

Top 95%
×5stories
+64ft-50ft

Overall

26876

Females

11492

F50-54

11492

20M→21M

20.0 - 21.0 mi

Top 93%
×8stories
+106ft-24ft

Overall

26327

Females

11227

F50-54

11227

21M→35K

21.0 - 21.8 mi

Top 96%
×7stories
+17ft-86ft

Overall

27172

Females

11677

F50-54

11677

35K→23M

21.8 - 23.0 mi

Top 99%
×5stories
+23ft-63ft

Overall

27982

Females

12084

F50-54

12084

23M→24M

23.0 - 24.0 mi

Top 94%
×6stories
+12ft-82ft

Overall

26667

Females

11460

F50-54

11460

24M→40K

24.0 - 24.9 mi

Top 91%
×1story
+6ft-20ft

Overall

25832

Females

11058

F50-54

11058

40K→25.2M

24.9 - 25.2 mi

Top 95%
×1story
+13ft-16ft

Overall

26878

Females

11606

F50-54

11606

25.2M→Finish

25.2 - 26.2 mi

Top 96%
×2stories
+22ft-21ft

Overall

27359

Females

11801

F50-54

11801

Passing Analysis

Category:
Athletes Passed
665
Passed By
312
Net Change
+353
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#27976
5K → 10K13333+100#27976#27876
10K → 15K5366-13#27876#27889
15K → 20K7134+37#27889#27852
20K → Half821-13#27852#27865
Half → 25K6927+42#27865#27823
25K → 30K9920+79#27823#27744
30K → 20M615+56#27744#27688
20M → 21M567+49#27688#27639
21M → 35K14140#27639#27639
35K → 23M1353-40#27639#27679
23M → 24M309+21#27679#27658
24M → 40K401+39#27658#27619
40K → 25.2M73+4#27619#27615
25.2M → Finish1119-8#27615#27623
TOTALS665312+353
📊

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