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BOSTON MARATHON 2023

John Shim

Bib: 5013•M

WA

0:00
0:00
/ mi
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Overall
#0 / 26622
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
22:58
Rank: #8773
Start → 5K
22:58 | 7:24/mi
10K· 6.21 mi
46:31
Rank: #9890 (-1117)
5K → 10K
23:33 | 7:35/mi
15K· 9.32 mi
1:10:45
Rank: #10846 (-956)
10K → 15K
24:14 | 7:48/mi
20K· 12.43 mi
1:35:19
Rank: #11260 (-414)
15K → 20K
24:34 | 7:54/mi
Half· 13.11 mi
1:40:46
Rank: #11425 (-165)
20K → Half
5:27 | 7:59/mi
25K· 15.53 mi
2:00:20
Rank: #11688 (-263)
Half → 25K
19:34 | 8:04/mi
30K· 18.64 mi
2:26:10
Rank: #11957 (-269)
25K → 30K
25:50 | 8:19/mi
20M
2:37:35
Rank: #12038 (-81)
30K → 20M
11:25 | 8:24/mi
21M
2:46:51
Rank: #12223 (-185)
20M → 21M
9:16 | 9:16/mi
35K· 21.75 mi
2:53:50
Rank: #12574 (-351)
21M → 35K
6:59 | 9:20/mi
23M
3:05:30
Rank: #12943 (-369)
35K → 23M
11:40 | 9:19/mi
24M
3:14:26
Rank: #13131 (-188)
23M → 24M
8:56 | 8:56/mi
40K· 24.85 mi
3:21:47
Rank: #13146 (-15)
24M → 40K
7:21 | 8:36/mi
25.2M
3:25:08
Rank: #13184 (-38)
40K → 25.2M
3:21 | 9:43/mi
Finish· 26.22 mi
3:34:39
Rank: #13536 (-352)
25.2M → Finish
9:31 | 9:20/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:40:46
Pace7:41 /mi
2nd Half
Distance13.11 mi
Time1:53:53
Pace8:41 /mi
📊Positive Split: 13.0% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:27:0222:587:2422:58
7:24
-
10K
6.21 mi10:50:3546:317:2923:33
7:35
+0:11
15K
9.32 mi11:14:491:10:457:3524:14
7:48
+0:13
20K
12.43 mi11:39:231:35:197:4024:34
7:54
+0:06
Half
13.11 mi11:44:501:40:467:415:27
7:59
+0:05
25K
15.53 mi12:04:242:00:207:4519:34
8:04
+0:05
30K
18.64 mi12:30:142:26:107:5025:50
8:19
+0:15
20M
20.00 mi12:41:392:37:357:5311:25
8:24
+0:05
21M
21.00 mi12:50:552:46:517:579:16
9:16
+0:52
35K
21.75 mi12:57:542:53:508:006:59
9:20
+0:04
23M
23.00 mi13:09:343:05:308:0411:40
9:19
-0:01
24M
24.00 mi13:18:303:14:268:068:56
8:56
-0:23
40K
24.85 mi13:25:513:21:478:077:21
8:36
-0:20
25.2M
25.20 mi13:29:123:25:088:083:21
9:43
+1:07
Finish
26.22 mi13:38:433:34:398:129:31
9:20
-0:23

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

7:24 /mi

Average Pace

8:12 /mi

Slowest Pace

9:43 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

1:40:46

47% of race

Time at Steady Pace

1:04:10

30% of race

Time at Slower Pace

49:43

23% of race

Average Pace: 8:11 /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 mi10:27:0222:587:2422:58
7:24
#8773
10K
6.21 mi10:50:3546:317:2923:33
7:35
#9890
15K
9.32 mi11:14:491:10:457:3524:14
7:48
#10846
20K
12.43 mi11:39:231:35:197:4024:34
7:54
#11260
Half
13.11 mi11:44:501:40:467:415:27
7:59
#11425
25K
15.53 mi12:04:242:00:207:4519:34
8:04
#11688
30K
18.64 mi12:30:142:26:107:5025:50
8:19
#11957
20M
20.00 mi12:41:392:37:357:5311:25
8:24
#12038
21M
21.00 mi12:50:552:46:517:579:16
9:16
#12223
35K
21.75 mi12:57:542:53:508:006:59
9:20
#12574
23M
23.00 mi13:09:343:05:308:0411:40
9:19
#12943
24M
24.00 mi13:18:303:14:268:068:56
8:56
#13131
40K
24.85 mi13:25:513:21:478:077:21
8:36
#13146
25.2M
25.20 mi13:29:123:25:088:083:21
9:43
#13184
Finish
26.22 mi13:38:433:34:398:129:31
9:20
#13536
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM18-39Seg. OverallSeg. MalesSeg. M18-39
5K3.11 mi3.11 mi87737466746612723(Top 48%)9401(Top 62%)9401(Top 178%)
10K6.21 mi3.10 mi9890-11178091-6258091-62511129(Top 42%)8730(Top 58%)8730(Top 165%)
15K9.32 mi3.11 mi10846-9568574-4838574-48312723(Top 48%)9401(Top 62%)9401(Top 178%)
20K12.43 mi3.11 mi11260-4148766-1928766-19212674(Top 48%)9291(Top 61%)9291(Top 176%)
Half13.11 mi0.68 mi11425-1658831-658831-6514210(Top 53%)9982(Top 66%)9982(Top 189%)
25K15.53 mi2.42 mi11688-2638920-898920-8913295(Top 50%)9475(Top 62%)9475(Top 179%)
30K18.64 mi3.11 mi11957-2698986-668986-6613107(Top 49%)9276(Top 61%)9276(Top 176%)
20M20.00 mi1.36 mi12038-818994-88994-813024(Top 49%)9134(Top 60%)9134(Top 173%)
21M21.00 mi1.00 mi12223-1859069-759069-7514781(Top 56%)9840(Top 65%)9840(Top 186%)
35K21.75 mi0.75 mi12574-3519205-1369205-13619254(Top 72%)11700(Top 77%)11700(Top 221%)
23M23.00 mi1.25 mi12943-3699332-1279332-12717578(Top 66%)10933(Top 72%)10933(Top 207%)
24M24.00 mi1.00 mi13131-1889388-569388-5616898(Top 63%)10575(Top 70%)10575(Top 200%)
40K24.85 mi0.85 mi13146-159375+139375+1313901(Top 52%)9191(Top 61%)9191(Top 174%)
25.2M25.20 mi0.35 mi13184-389379-49379-416108(Top 61%)10152(Top 67%)10152(Top 192%)
Finish26.22 mi1.02 mi13536-3529509-1309509-13019496(Top 73%)11741(Top 77%)11741(Top 222%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 48%
×21stories
+97ft-345ft

Overall

12723

Males

9401

M18-39

9401

5K→10K

3.1 - 6.2 mi

Top 42%
×5stories
+79ft-138ft

Overall

11129

Males

8730

M18-39

8730

10K→15K

6.2 - 9.3 mi

Top 48%
×3stories
+67ft-78ft

Overall

12723

Males

9401

M18-39

9401

15K→20K

9.3 - 12.4 mi

Top 48%
×5stories
+106ft-86ft

Overall

12674

Males

9291

M18-39

9291

20K→Half

12.4 - 13.1 mi

Top 53%
×2stories
+19ft-37ft

Overall

14210

Males

9982

M18-39

9982

Half→25K

13.1 - 15.5 mi

Top 50%
×4stories
+66ft-88ft

Overall

13295

Males

9475

M18-39

9475

25K→30K

15.5 - 18.6 mi

Top 49%
×9stories
+181ft-148ft

Overall

13107

Males

9276

M18-39

9276

30K→20M

18.6 - 20.0 mi

Top 49%
×5stories
+64ft-50ft

Overall

13024

Males

9134

M18-39

9134

20M→21M

20.0 - 21.0 mi

Top 56%
×8stories
+106ft-24ft

Overall

14781

Males

9840

M18-39

9840

21M→35K

21.0 - 21.8 mi

Top 72%
×7stories
+17ft-86ft

Overall

19254

Males

11700

M18-39

11700

35K→23M

21.8 - 23.0 mi

Top 66%
×5stories
+23ft-63ft

Overall

17578

Males

10933

M18-39

10933

23M→24M

23.0 - 24.0 mi

Top 63%
×6stories
+12ft-82ft

Overall

16898

Males

10575

M18-39

10575

24M→40K

24.0 - 24.9 mi

Top 52%
×1story
+6ft-20ft

Overall

13901

Males

9191

M18-39

9191

40K→25.2M

24.9 - 25.2 mi

Top 61%
×1story
+13ft-16ft

Overall

16108

Males

10152

M18-39

10152

25.2M→Finish

25.2 - 26.2 mi

Top 73%
×2stories
+22ft-21ft

Overall

19496

Males

11741

M18-39

11741

Passing Analysis

Category:
Athletes Passed
554
Passed By
5315
Net Change
-4763
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#8773
5K → 10K361153-1117#8773#9890
10K → 15K23977-956#9890#10846
15K → 20K61475-414#10846#11260
20K → Half5170-165#11260#11425
Half → 25K63326-263#11425#11688
25K → 30K105374-269#11688#11957
30K → 20M83164-81#11957#12038
20M → 21M36221-185#12038#12223
21M → 35K6357-351#12223#12574
35K → 23M19388-369#12574#12943
23M → 24M25213-188#12943#13131
24M → 40K5368-15#13131#13146
40K → 25.2M3169-38#13146#13184
25.2M → Finish8360-352#13184#13536
TOTALS5545315-4763
📊

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