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BOSTON MARATHON 2023

Sam Belcher

Bib: 2737•M

MA

0:00
0:00
/ mi
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Overall
#0 / 26622
Top 37%
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
21:42
Rank: #6166
Start → 5K
21:42 | 6:59/mi
10K· 6.21 mi
43:48
Rank: #6802 (-636)
5K → 10K
22:06 | 7:07/mi
15K· 9.32 mi
1:06:27
Rank: #7293 (-491)
10K → 15K
22:39 | 7:17/mi
20K· 12.43 mi
1:28:58
Rank: #7267 (+26)
15K → 20K
22:31 | 7:15/mi
Half· 13.11 mi
1:33:48
Rank: #7264 (+3)
20K → Half
4:50 | 7:05/mi
25K· 15.53 mi
1:51:43
Rank: #7318 (-54)
Half → 25K
17:55 | 7:23/mi
30K· 18.64 mi
2:15:36
Rank: #7456 (-138)
25K → 30K
23:53 | 7:41/mi
20M
2:26:40
Rank: #7689 (-233)
30K → 20M
11:04 | 8:09/mi
21M
2:36:24
Rank: #8254 (-565)
20M → 21M
9:44 | 9:44/mi
35K· 21.75 mi
2:42:53
Rank: #8555 (-301)
21M → 35K
6:29 | 8:40/mi
23M
2:53:52
Rank: #8925 (-370)
35K → 23M
10:59 | 8:46/mi
24M
3:02:41
Rank: #9236 (-311)
23M → 24M
8:49 | 8:49/mi
40K· 24.85 mi
3:10:11
Rank: #9453 (-217)
24M → 40K
7:30 | 8:46/mi
25.2M
3:13:40
Rank: #9598 (-145)
40K → 25.2M
3:29 | 10:06/mi
Finish· 26.22 mi
3:22:32
Rank: #9891 (-293)
25.2M → Finish
8:52 | 8:42/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:33:48
Pace7:09 /mi
2nd Half
Distance13.11 mi
Time1:48:44
Pace8:18 /mi
📊Positive Split: 15.9% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:22:2921:426:5921:42
6:59
-
10K
6.21 mi10:44:3543:487:0322:06
7:07
+0:08
15K
9.32 mi11:07:141:06:277:0822:39
7:17
+0:10
20K
12.43 mi11:29:451:28:587:1022:31
7:15
-0:02
Half
13.11 mi11:34:351:33:487:094:50
7:05
-0:10
25K
15.53 mi11:52:301:51:437:1117:55
7:23
+0:18
30K
18.64 mi12:16:232:15:367:1623:53
7:41
+0:18
20M
20.00 mi12:27:272:26:407:2011:04
8:09
+0:28
21M
21.00 mi12:37:112:36:247:279:44
9:44
+1:35
35K
21.75 mi12:43:402:42:537:296:29
8:40
-1:04
23M
23.00 mi12:54:392:53:527:3410:59
8:46
+0:06
24M
24.00 mi13:03:283:02:417:378:49
8:49
+0:03
40K
24.85 mi13:10:583:10:117:397:30
8:46
-0:03
25.2M
25.20 mi13:14:273:13:407:413:29
10:06
+1:20
Finish
26.22 mi13:23:193:22:327:448:52
8:42
-1:24

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

6:59 /mi

Average Pace

7:44 /mi

Slowest Pace

10:06 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

1:51:43

55% of race

Time at Steady Pace

34:57

17% of race

Time at Slower Pace

55:52

28% of race

Average Pace: 7:43 /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 mi10:22:2921:426:5921:42
6:59
#6166
10K
6.21 mi10:44:3543:487:0322:06
7:07
#6802
15K
9.32 mi11:07:141:06:277:0822:39
7:17
#7293
20K
12.43 mi11:29:451:28:587:1022:31
7:15
#7267
Half
13.11 mi11:34:351:33:487:094:50
7:05
#7264
25K
15.53 mi11:52:301:51:437:1117:55
7:23
#7318
30K
18.64 mi12:16:232:15:367:1623:53
7:41
#7456
20M
20.00 mi12:27:272:26:407:2011:04
8:09
#7689
21M
21.00 mi12:37:112:36:247:279:44
9:44
#8254
35K
21.75 mi12:43:402:42:537:296:29
8:40
#8555
23M
23.00 mi12:54:392:53:527:3410:59
8:46
#8925
24M
24.00 mi13:03:283:02:417:378:49
8:49
#9236
40K
24.85 mi13:10:583:10:117:397:30
8:46
#9453
25.2M
25.20 mi13:14:273:13:407:413:29
10:06
#9598
Finish
26.22 mi13:23:193:22:327:448:52
8:42
#9891
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM18-39Seg. OverallSeg. MalesSeg. M18-39
5K3.11 mi3.11 mi6166563156318477(Top 32%)7227(Top 48%)7227(Top 137%)
10K6.21 mi3.10 mi6802-6366119-4886119-4887537(Top 28%)6632(Top 44%)6632(Top 125%)
15K9.32 mi3.11 mi7293-4916470-3516470-3518477(Top 32%)7227(Top 48%)7227(Top 137%)
20K12.43 mi3.11 mi7267+266440+306440+307415(Top 28%)6506(Top 43%)6506(Top 123%)
Half13.11 mi0.68 mi7264+36439+16439+17077(Top 27%)6294(Top 41%)6294(Top 119%)
25K15.53 mi2.42 mi7318-546468-296468-297942(Top 30%)6771(Top 45%)6771(Top 128%)
30K18.64 mi3.11 mi7456-1386534-666534-668546(Top 32%)7014(Top 46%)7014(Top 133%)
20M20.00 mi1.36 mi7689-2336661-1276661-12711291(Top 42%)8398(Top 55%)8398(Top 159%)
21M21.00 mi1.00 mi8254-5656998-3376998-33716956(Top 64%)10768(Top 71%)10768(Top 204%)
35K21.75 mi0.75 mi8555-3017177-1797177-17916186(Top 61%)10348(Top 68%)10348(Top 196%)
23M23.00 mi1.25 mi8925-3707377-2007377-20014804(Top 56%)9712(Top 64%)9712(Top 184%)
24M24.00 mi1.00 mi9236-3117533-1567533-15616247(Top 61%)10271(Top 68%)10271(Top 194%)
40K24.85 mi0.85 mi9453-2177628-957628-9514891(Top 56%)9625(Top 63%)9625(Top 182%)
25.2M25.20 mi0.35 mi9598-1457702-747702-7417704(Top 67%)10863(Top 72%)10863(Top 206%)
Finish26.22 mi1.02 mi9891-2937834-1327834-13216459(Top 62%)10356(Top 68%)10356(Top 196%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 32%
×21stories
+97ft-345ft

Overall

8477

Males

7227

M18-39

7227

5K→10K

3.1 - 6.2 mi

Top 28%
×5stories
+79ft-138ft

Overall

7537

Males

6632

M18-39

6632

10K→15K

6.2 - 9.3 mi

Top 32%
×3stories
+67ft-78ft

Overall

8477

Males

7227

M18-39

7227

15K→20K

9.3 - 12.4 mi

Top 28%
×5stories
+106ft-86ft

Overall

7415

Males

6506

M18-39

6506

20K→Half

12.4 - 13.1 mi

Top 27%
×2stories
+19ft-37ft

Overall

7077

Males

6294

M18-39

6294

Half→25K

13.1 - 15.5 mi

Top 30%
×4stories
+66ft-88ft

Overall

7942

Males

6771

M18-39

6771

25K→30K

15.5 - 18.6 mi

Top 32%
×9stories
+181ft-148ft

Overall

8546

Males

7014

M18-39

7014

30K→20M

18.6 - 20.0 mi

Top 42%
×5stories
+64ft-50ft

Overall

11291

Males

8398

M18-39

8398

20M→21M

20.0 - 21.0 mi

Top 64%
×8stories
+106ft-24ft

Overall

16956

Males

10768

M18-39

10768

21M→35K

21.0 - 21.8 mi

Top 61%
×7stories
+17ft-86ft

Overall

16186

Males

10348

M18-39

10348

35K→23M

21.8 - 23.0 mi

Top 56%
×5stories
+23ft-63ft

Overall

14804

Males

9712

M18-39

9712

23M→24M

23.0 - 24.0 mi

Top 61%
×6stories
+12ft-82ft

Overall

16247

Males

10271

M18-39

10271

24M→40K

24.0 - 24.9 mi

Top 56%
×1story
+6ft-20ft

Overall

14891

Males

9625

M18-39

9625

40K→25.2M

24.9 - 25.2 mi

Top 67%
×1story
+13ft-16ft

Overall

17704

Males

10863

M18-39

10863

25.2M→Finish

25.2 - 26.2 mi

Top 62%
×2stories
+22ft-21ft

Overall

16459

Males

10356

M18-39

10356

Passing Analysis

Category:
Athletes Passed
457
Passed By
4182
Net Change
-3725
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#6166
5K → 10K26662-636#6166#6802
10K → 15K21512-491#6802#7293
15K → 20K126100+26#7293#7267
20K → Half2320+3#7267#7264
Half → 25K57111-54#7264#7318
25K → 30K89227-138#7318#7456
30K → 20M26259-233#7456#7689
20M → 21M3568-565#7689#8254
21M → 35K6307-301#8254#8555
35K → 23M19389-370#8555#8925
23M → 24M16327-311#8925#9236
24M → 40K23240-217#9236#9453
40K → 25.2M8153-145#9453#9598
25.2M → Finish14307-293#9598#9891
TOTALS4574182-3725
📊

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