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BOSTON MARATHON 2023

Simon Kalechstein

Bib: 5249•M

ON

0:00
0:00
/ mi
Masters
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Overall
#0 / 26622
Top 13%
Gender (Male)
#0 / 15176
Top 21%
Masters (Masters Men)
#0 / 9891
Top 9%
Division (M40-44)
#0 / 2241
Top 22%
Race Day Weather
49°/39°F
light intensity drizzle

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
20:53
Rank: #3858
Start → 5K
20:53 | 6:43/mi
10K· 6.21 mi
41:53
Rank: #4380 (-522)
5K → 10K
21:00 | 6:46/mi
15K· 9.32 mi
1:02:36
Rank: #4169 (+211)
10K → 15K
20:43 | 6:40/mi
20K· 12.43 mi
1:23:24
Rank: #3973 (+196)
15K → 20K
20:48 | 6:42/mi
Half· 13.11 mi
1:27:53
Rank: #3920 (+53)
20K → Half
4:29 | 6:34/mi
25K· 15.53 mi
1:44:09
Rank: #3814 (+106)
Half → 25K
16:16 | 6:43/mi
30K· 18.64 mi
2:05:16
Rank: #3612 (+202)
25K → 30K
21:07 | 6:48/mi
20M
2:14:35
Rank: #3531 (+81)
30K → 20M
9:19 | 6:51/mi
21M
2:21:47
Rank: #3464 (+67)
20M → 21M
7:12 | 7:12/mi
35K· 21.75 mi
2:26:50
Rank: #3462 (+2)
21M → 35K
5:03 | 6:45/mi
23M
2:35:29
Rank: #3417 (+45)
35K → 23M
8:39 | 6:55/mi
24M
2:42:15
Rank: #3406 (+11)
23M → 24M
6:46 | 6:46/mi
40K· 24.85 mi
2:48:13
Rank: #3402 (+4)
24M → 40K
5:58 | 6:59/mi
25.2M
2:50:46
Rank: #3402
40K → 25.2M
2:33 | 7:24/mi
Finish· 26.22 mi
2:57:42
Rank: #3388 (+14)
25.2M → Finish
6:56 | 6:48/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:27:53
Pace6:42 /mi
2nd Half
Distance13.11 mi
Time1:29:49
Pace6:51 /mi
📊Positive Split: 2.2% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:23:5220:536:4320:53
6:43
-
10K
6.21 mi10:44:5241:536:4421:00
6:46
+0:03
15K
9.32 mi11:05:351:02:366:4320:43
6:40
-0:06
20K
12.43 mi11:26:231:23:246:4320:48
6:42
+0:02
Half
13.11 mi11:30:521:27:536:424:29
6:34
-0:08
25K
15.53 mi11:47:081:44:096:4216:16
6:43
+0:09
30K
18.64 mi12:08:152:05:166:4321:07
6:48
+0:05
20M
20.00 mi12:17:342:14:356:449:19
6:51
+0:03
21M
21.00 mi12:24:462:21:476:457:12
7:12
+0:21
35K
21.75 mi12:29:492:26:506:455:03
6:45
-0:27
23M
23.00 mi12:38:282:35:296:468:39
6:55
+0:10
24M
24.00 mi12:45:142:42:156:466:46
6:46
-0:09
40K
24.85 mi12:51:122:48:136:465:58
6:59
+0:13
25.2M
25.20 mi12:53:452:50:466:472:33
7:24
+0:25
Finish
26.22 mi13:00:412:57:426:476:56
6:48
-0:36

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

6:34 /mi

Average Pace

6:47 /mi

Slowest Pace

7:24 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

2:55:09

99% of race

Time at Steady Pace

2:33

1% of race

Time at Slower Pace

0:00

0% of race

Average Pace: 6:47 /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 mi10:23:5220:536:4320:53
6:43
#3858
10K
6.21 mi10:44:5241:536:4421:00
6:46
#4380
15K
9.32 mi11:05:351:02:366:4320:43
6:40
#4169
20K
12.43 mi11:26:231:23:246:4320:48
6:42
#3973
Half
13.11 mi11:30:521:27:536:424:29
6:34
#3920
25K
15.53 mi11:47:081:44:096:4216:16
6:43
#3814
30K
18.64 mi12:08:152:05:166:4321:07
6:48
#3612
20M
20.00 mi12:17:342:14:356:449:19
6:51
#3531
21M
21.00 mi12:24:462:21:476:457:12
7:12
#3464
35K
21.75 mi12:29:492:26:506:455:03
6:45
#3462
23M
23.00 mi12:38:282:35:296:468:39
6:55
#3417
24M
24.00 mi12:45:142:42:156:466:46
6:46
#3406
40K
24.85 mi12:51:122:48:136:465:58
6:59
#3402
25.2M
25.20 mi12:53:452:50:466:472:33
7:24
#3402
Finish
26.22 mi13:00:412:57:426:476:56
6:48
#3388
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM40-44Seg. OverallSeg. MalesSeg. M40-44
5K3.11 mi3.11 mi3858362436243823(Top 14%)3594(Top 24%)3594(Top 160%)
10K6.21 mi3.10 mi4380-5224101-4774101-4774886(Top 18%)4531(Top 30%)4531(Top 202%)
15K9.32 mi3.11 mi4169+2113913+1883913+1883823(Top 14%)3594(Top 24%)3594(Top 160%)
20K12.43 mi3.11 mi3973+1963739+1743739+1743540(Top 13%)3349(Top 22%)3349(Top 149%)
Half13.11 mi0.68 mi3920+533691+483691+483239(Top 12%)3089(Top 20%)3089(Top 138%)
25K15.53 mi2.42 mi3814+1063601+903601+903417(Top 13%)3238(Top 21%)3238(Top 144%)
30K18.64 mi3.11 mi3612+2023416+1853416+1852971(Top 11%)2813(Top 19%)2813(Top 126%)
20M20.00 mi1.36 mi3531+813340+763340+763158(Top 12%)2964(Top 20%)2964(Top 132%)
21M21.00 mi1.00 mi3464+673280+603280+603095(Top 12%)2899(Top 19%)2899(Top 129%)
35K21.75 mi0.75 mi3462+23279+13279+13842(Top 14%)3536(Top 23%)3536(Top 158%)
23M23.00 mi1.25 mi3417+453233+463233+463272(Top 12%)3041(Top 20%)3041(Top 136%)
24M24.00 mi1.00 mi3406+113220+133220+133464(Top 13%)3189(Top 21%)3189(Top 142%)
40K24.85 mi0.85 mi3402+43214+63214+63706(Top 14%)3347(Top 22%)3347(Top 149%)
25.2M25.20 mi0.35 mi34023213+13213+13366(Top 13%)3049(Top 20%)3049(Top 136%)
Finish26.22 mi1.02 mi3388+143196+173196+174071(Top 15%)3592(Top 24%)3592(Top 160%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 14%
×21stories
+97ft-345ft

Overall

3823

Males

3594

M40-44

3594

5K→10K

3.1 - 6.2 mi

Top 18%
×5stories
+79ft-138ft

Overall

4886

Males

4531

M40-44

4531

10K→15K

6.2 - 9.3 mi

Top 14%
×3stories
+67ft-78ft

Overall

3823

Males

3594

M40-44

3594

15K→20K

9.3 - 12.4 mi

Top 13%
×5stories
+106ft-86ft

Overall

3540

Males

3349

M40-44

3349

20K→Half

12.4 - 13.1 mi

Top 12%
×2stories
+19ft-37ft

Overall

3239

Males

3089

M40-44

3089

Half→25K

13.1 - 15.5 mi

Top 13%
×4stories
+66ft-88ft

Overall

3417

Males

3238

M40-44

3238

25K→30K

15.5 - 18.6 mi

Top 11%
×9stories
+181ft-148ft

Overall

2971

Males

2813

M40-44

2813

30K→20M

18.6 - 20.0 mi

Top 12%
×5stories
+64ft-50ft

Overall

3158

Males

2964

M40-44

2964

20M→21M

20.0 - 21.0 mi

Top 12%
×8stories
+106ft-24ft

Overall

3095

Males

2899

M40-44

2899

21M→35K

21.0 - 21.8 mi

Top 14%
×7stories
+17ft-86ft

Overall

3842

Males

3536

M40-44

3536

35K→23M

21.8 - 23.0 mi

Top 12%
×5stories
+23ft-63ft

Overall

3272

Males

3041

M40-44

3041

23M→24M

23.0 - 24.0 mi

Top 13%
×6stories
+12ft-82ft

Overall

3464

Males

3189

M40-44

3189

24M→40K

24.0 - 24.9 mi

Top 14%
×1story
+6ft-20ft

Overall

3706

Males

3347

M40-44

3347

40K→25.2M

24.9 - 25.2 mi

Top 13%
×1story
+13ft-16ft

Overall

3366

Males

3049

M40-44

3049

25.2M→Finish

25.2 - 26.2 mi

Top 15%
×2stories
+22ft-21ft

Overall

4071

Males

3592

M40-44

3592

Passing Analysis

Category:
Athletes Passed
1429
Passed By
959
Net Change
+470
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#3858
5K → 10K65587-522#3858#4380
10K → 15K25645+211#4380#4169
15K → 20K21822+196#4169#3973
20K → Half585+53#3973#3920
Half → 25K14034+106#3920#3814
25K → 30K22220+202#3814#3612
30K → 20M10019+81#3612#3531
20M → 21M8518+67#3531#3464
21M → 35K4139+2#3464#3462
35K → 23M8237+45#3462#3417
23M → 24M4433+11#3417#3406
24M → 40K4036+4#3406#3402
40K → 25.2M21210#3402#3402
25.2M → Finish5743+14#3402#3388
TOTALS1429959+470
📊

Passing Visuals

Category:

📈Position Graph

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🎨Heatmap Timeline

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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