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BOSTON MARATHON 2023

Jefferson Chan

Bib: 3764•M

TX

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0:00
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Overall
#0 / 26622
Top 40%
Gender (Male)
#0 / 15176
Division (M18-39)
#0 / 5285
Race Day Weather
49°/39°F
light intensity drizzle

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
20:50
Rank: #3735
Start → 5K
20:50 | 6:42/mi
10K· 6.21 mi
41:02
Rank: #3196 (+539)
5K → 10K
20:12 | 6:30/mi
15K· 9.32 mi
1:01:26
Rank: #3135 (+61)
10K → 15K
20:24 | 6:34/mi
20K· 12.43 mi
1:22:46
Rank: #3531 (-396)
15K → 20K
21:20 | 6:52/mi
Half· 13.11 mi
1:27:18
Rank: #3535 (-4)
20K → Half
4:32 | 6:39/mi
25K· 15.53 mi
1:44:02
Rank: #3750 (-215)
Half → 25K
16:44 | 6:54/mi
30K· 18.64 mi
2:06:40
Rank: #4272 (-522)
25K → 30K
22:38 | 7:17/mi
20M
2:17:42
Rank: #4858 (-586)
30K → 20M
11:02 | 8:07/mi
21M
2:30:59
Rank: #6520 (-1662)
20M → 21M
13:17 | 13:17/mi
35K· 21.75 mi
2:42:24
Rank: #8402 (-1882)
21M → 35K
11:25 | 15:16/mi
23M
2:55:08
Rank: #9317 (-915)
35K → 23M
12:44 | 10:10/mi
24M
3:04:48
Rank: #9937 (-620)
23M → 24M
9:40 | 9:40/mi
40K· 24.85 mi
3:12:57
Rank: #10342 (-405)
24M → 40K
8:09 | 9:32/mi
25.2M
3:16:24
Rank: #10489 (-147)
40K → 25.2M
3:27 | 10:00/mi
Finish· 26.22 mi
3:24:45
Rank: #10577 (-88)
25.2M → Finish
8:21 | 8:12/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:27:18
Pace6:40 /mi
2nd Half
Distance13.11 mi
Time1:57:27
Pace8:58 /mi
📊Positive Split: 34.5% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:22:0320:506:4220:50
6:42
-
10K
6.21 mi10:42:1541:026:3620:12
6:30
-0:12
15K
9.32 mi11:02:391:01:266:3520:24
6:34
+0:04
20K
12.43 mi11:23:591:22:466:4021:20
6:52
+0:18
Half
13.11 mi11:28:311:27:186:404:32
6:39
-0:13
25K
15.53 mi11:45:151:44:026:4216:44
6:54
+0:15
30K
18.64 mi12:07:532:06:406:4822:38
7:17
+0:23
20M
20.00 mi12:18:552:17:426:5311:02
8:07
+0:50
21M
21.00 mi12:32:122:30:597:1113:17
13:17
+5:10
35K
21.75 mi12:43:372:42:247:2811:25
15:16
+1:59
23M
23.00 mi12:56:212:55:087:3712:44
10:10
-5:06
24M
24.00 mi13:06:013:04:487:429:40
9:40
-0:30
40K
24.85 mi13:14:103:12:577:468:09
9:32
-0:08
25.2M
25.20 mi13:17:373:16:247:483:27
10:00
+0:28
Finish
26.22 mi13:25:583:24:457:498:21
8:12
-1:48

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

6:30 /mi

Average Pace

7:49 /mi

Slowest Pace

15:16 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

1:05:58

32% of race

Time at Steady Pace

1:20:05

39% of race

Time at Slower Pace

58:42

29% 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 mi10:22:0320:506:4220:50
6:42
#3735
10K
6.21 mi10:42:1541:026:3620:12
6:30
#3196
15K
9.32 mi11:02:391:01:266:3520:24
6:34
#3135
20K
12.43 mi11:23:591:22:466:4021:20
6:52
#3531
Half
13.11 mi11:28:311:27:186:404:32
6:39
#3535
25K
15.53 mi11:45:151:44:026:4216:44
6:54
#3750
30K
18.64 mi12:07:532:06:406:4822:38
7:17
#4272
20M
20.00 mi12:18:552:17:426:5311:02
8:07
#4858
21M
21.00 mi12:32:122:30:597:1113:17
13:17
#6520
35K
21.75 mi12:43:372:42:247:2811:25
15:16
#8402
23M
23.00 mi12:56:212:55:087:3712:44
10:10
#9317
24M
24.00 mi13:06:013:04:487:429:40
9:40
#9937
40K
24.85 mi13:14:103:12:577:468:09
9:32
#10342
25.2M
25.20 mi13:17:373:16:247:483:27
10:00
#10489
Finish
26.22 mi13:25:583:24:457:498:21
8:12
#10577
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM18-39Seg. OverallSeg. MalesSeg. M18-39
5K3.11 mi3.11 mi3735351135113044(Top 11%)2903(Top 19%)2903(Top 55%)
10K6.21 mi3.10 mi3196+5393034+4773034+4772813(Top 11%)2689(Top 18%)2689(Top 51%)
15K9.32 mi3.11 mi3135+612986+482986+483044(Top 11%)2903(Top 19%)2903(Top 55%)
20K12.43 mi3.11 mi3531-3963344-3583344-3585085(Top 19%)4708(Top 31%)4708(Top 89%)
Half13.11 mi0.68 mi3535-43348-43348-43900(Top 15%)3684(Top 24%)3684(Top 70%)
25K15.53 mi2.42 mi3750-2153545-1973545-1974987(Top 19%)4616(Top 30%)4616(Top 87%)
30K18.64 mi3.11 mi4272-5224007-4624007-4625944(Top 22%)5337(Top 35%)5337(Top 101%)
20M20.00 mi1.36 mi4858-5864515-5084515-50811131(Top 42%)8315(Top 55%)8315(Top 157%)
21M21.00 mi1.00 mi6520-16625829-13145829-131424370(Top 92%)14066(Top 93%)14066(Top 266%)
35K21.75 mi0.75 mi8402-18827083-12547083-125426450(Top 99%)15081(Top 99%)15081(Top 285%)
23M23.00 mi1.25 mi9317-9157602-5197602-51920473(Top 77%)12233(Top 81%)12233(Top 231%)
24M24.00 mi1.00 mi9937-6207923-3217923-32119754(Top 74%)11888(Top 78%)11888(Top 225%)
40K24.85 mi0.85 mi10342-4058103-1808103-18018415(Top 69%)11222(Top 74%)11222(Top 212%)
25.2M25.20 mi0.35 mi10489-1478161-588161-5817315(Top 65%)10668(Top 70%)10668(Top 202%)
Finish26.22 mi1.02 mi10577-888176-158176-1513361(Top 50%)8946(Top 59%)8946(Top 169%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 11%
×21stories
+97ft-345ft

Overall

3044

Males

2903

M18-39

2903

5K→10K

3.1 - 6.2 mi

Top 11%
×5stories
+79ft-138ft

Overall

2813

Males

2689

M18-39

2689

10K→15K

6.2 - 9.3 mi

Top 11%
×3stories
+67ft-78ft

Overall

3044

Males

2903

M18-39

2903

15K→20K

9.3 - 12.4 mi

Top 19%
×5stories
+106ft-86ft

Overall

5085

Males

4708

M18-39

4708

20K→Half

12.4 - 13.1 mi

Top 15%
×2stories
+19ft-37ft

Overall

3900

Males

3684

M18-39

3684

Half→25K

13.1 - 15.5 mi

Top 19%
×4stories
+66ft-88ft

Overall

4987

Males

4616

M18-39

4616

25K→30K

15.5 - 18.6 mi

Top 22%
×9stories
+181ft-148ft

Overall

5944

Males

5337

M18-39

5337

30K→20M

18.6 - 20.0 mi

Top 42%
×5stories
+64ft-50ft

Overall

11131

Males

8315

M18-39

8315

20M→21M

20.0 - 21.0 mi

Top 92%
×8stories
+106ft-24ft

Overall

24370

Males

14066

M18-39

14066

21M→35K

21.0 - 21.8 mi

Top 99%
×7stories
+17ft-86ft

Overall

26450

Males

15081

M18-39

15081

35K→23M

21.8 - 23.0 mi

Top 77%
×5stories
+23ft-63ft

Overall

20473

Males

12233

M18-39

12233

23M→24M

23.0 - 24.0 mi

Top 74%
×6stories
+12ft-82ft

Overall

19754

Males

11888

M18-39

11888

24M→40K

24.0 - 24.9 mi

Top 69%
×1story
+6ft-20ft

Overall

18415

Males

11222

M18-39

11222

40K→25.2M

24.9 - 25.2 mi

Top 65%
×1story
+13ft-16ft

Overall

17315

Males

10668

M18-39

10668

25.2M→Finish

25.2 - 26.2 mi

Top 50%
×2stories
+22ft-21ft

Overall

13361

Males

8946

M18-39

8946

Passing Analysis

Category:
Athletes Passed
876
Passed By
7716
Net Change
-6842
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#3735
5K → 10K56728+539#3735#3196
10K → 15K12564+61#3196#3135
15K → 20K21417-396#3135#3531
20K → Half1014-4#3531#3535
Half → 25K38253-215#3535#3750
25K → 30K25547-522#3750#4272
30K → 20M6592-586#4272#4858
20M → 21M01662-1662#4858#6520
21M → 35K01882-1882#6520#8402
35K → 23M6921-915#8402#9317
23M → 24M4623-620#9317#9937
24M → 40K16420-405#9937#10342
40K → 25.2M7154-147#10342#10489
25.2M → Finish51139-88#10489#10577
TOTALS8767716-6842
📊

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