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BOSTON MARATHON 2023

Cosmo Brossy

Bib: 325•M

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Overall
#0 / 26622
Top 0.4%
Gender (Male)
#0 / 15176
Top 0.6%
Division (M18-39)
#0 / 5285
Top 2%
Race Day Weather
49°/39°F
light intensity drizzle

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
17:33
Rank: #214
Start → 5K
17:33 | 5:39/mi
10K· 6.21 mi
35:10
Rank: #245 (-31)
5K → 10K
17:37 | 5:40/mi
15K· 9.32 mi
52:51
Rank: #238 (+7)
10K → 15K
17:41 | 5:42/mi
20K· 12.43 mi
1:10:45
Rank: #246 (-8)
15K → 20K
17:54 | 5:46/mi
Half· 13.11 mi
1:14:35
Rank: #246
20K → Half
3:50 | 5:37/mi
25K· 15.53 mi
1:28:32
Rank: #234 (+12)
Half → 25K
13:57 | 5:45/mi
30K· 18.64 mi
1:46:49
Rank: #225 (+9)
25K → 30K
18:17 | 5:53/mi
20M
1:54:43
Rank: #207 (+18)
30K → 20M
7:54 | 5:49/mi
21M
2:00:36
Rank: #189 (+18)
20M → 21M
5:53 | 5:53/mi
35K· 21.75 mi
2:04:37
Rank: #184 (+5)
21M → 35K
4:01 | 5:22/mi
23M
2:11:26
Rank: #165 (+19)
35K → 23M
6:49 | 5:27/mi
24M
2:16:42
Rank: #147 (+18)
23M → 24M
5:16 | 5:16/mi
40K· 24.85 mi
2:21:16
Rank: #132 (+15)
24M → 40K
4:34 | 5:20/mi
25.2M
2:23:13
Rank: #131 (+1)
40K → 25.2M
1:57 | 5:39/mi
Finish· 26.22 mi
2:28:25
Rank: #117 (+14)
25.2M → Finish
5:12 | 5:06/mi

The Course

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Half Splits

1st Half· via Half
Distance13.11 mi
Time1:14:35
Pace5:41 /mi
2nd Half✓ Faster
Distance13.11 mi
Time1:13:50
Pace5:38 /mi
📊Negative Split: 1.0% faster second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:17:4017:335:3917:33
5:39
-
10K
6.21 mi10:35:1735:105:4017:37
5:40
+0:01
15K
9.32 mi10:52:5852:515:4017:41
5:42
+0:02
20K
12.43 mi11:10:521:10:455:4217:54
5:46
+0:04
Half
13.11 mi11:14:421:14:355:413:50
5:37
-0:09
25K
15.53 mi11:28:391:28:325:4213:57
5:45
+0:08
30K
18.64 mi11:46:561:46:495:4418:17
5:53
+0:08
20M
20.00 mi11:54:501:54:435:447:54
5:49
-0:04
21M
21.00 mi12:00:432:00:365:455:53
5:53
+0:04
35K
21.75 mi12:04:442:04:375:444:01
5:22
-0:31
23M
23.00 mi12:11:332:11:265:436:49
5:27
+0:05
24M
24.00 mi12:16:492:16:425:425:16
5:16
-0:11
40K
24.85 mi12:21:232:21:165:414:34
5:20
+0:04
25.2M
25.20 mi12:23:202:23:135:411:57
5:39
+0:19
Finish
26.22 mi12:28:322:28:255:405:12
5:06
-0:33

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

5:06 /mi

Average Pace

5:40 /mi

Slowest Pace

5:53 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

25:52

17% of race

Time at Steady Pace

2:02:33

83% of race

Time at Slower Pace

0:00

0% of race

Average Pace: 5:40 /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 mi10:17:4017:335:3917:33
5:39
#214
10K
6.21 mi10:35:1735:105:4017:37
5:40
#245
15K
9.32 mi10:52:5852:515:4017:41
5:42
#238
20K
12.43 mi11:10:521:10:455:4217:54
5:46
#246
Half
13.11 mi11:14:421:14:355:413:50
5:37
#246
25K
15.53 mi11:28:391:28:325:4213:57
5:45
#234
30K
18.64 mi11:46:561:46:495:4418:17
5:53
#225
20M
20.00 mi11:54:501:54:435:447:54
5:49
#207
21M
21.00 mi12:00:432:00:365:455:53
5:53
#189
35K
21.75 mi12:04:442:04:375:444:01
5:22
#184
23M
23.00 mi12:11:332:11:265:436:49
5:27
#165
24M
24.00 mi12:16:492:16:425:425:16
5:16
#147
40K
24.85 mi12:21:232:21:165:414:34
5:20
#132
25.2M
25.20 mi12:23:202:23:135:411:57
5:39
#131
Finish
26.22 mi12:28:322:28:255:405:12
5:06
#117
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM18-39Seg. OverallSeg. MalesSeg. M18-39
5K3.11 mi3.11 mi214214214233(Top 0.9%)204(Top 1%)204(Top 4%)
10K6.21 mi3.10 mi245-31218-4218-4267(Top 1%)237(Top 2%)237(Top 4%)
15K9.32 mi3.11 mi238+7211+7211+7233(Top 0.9%)204(Top 1%)204(Top 4%)
20K12.43 mi3.11 mi246-8219-8219-8247(Top 0.9%)220(Top 1%)220(Top 4%)
Half13.11 mi0.68 mi246218+1218+1196(Top 0.7%)174(Top 1%)174(Top 3%)
25K15.53 mi2.42 mi234+12207+11207+11215(Top 0.8%)192(Top 1%)192(Top 4%)
30K18.64 mi3.11 mi225+9200+7200+7230(Top 0.9%)206(Top 1%)206(Top 4%)
20M20.00 mi1.36 mi207+18183+17183+17162(Top 0.6%)140(Top 0.9%)140(Top 3%)
21M21.00 mi1.00 mi189+18166+17166+1770(Top 0.3%)59(Top 0.4%)59(Top 1%)
35K21.75 mi0.75 mi184+5161+5161+560(Top 0.2%)46(Top 0.3%)46(Top 0.9%)
23M23.00 mi1.25 mi165+19143+18143+1834(Top 0.1%)27(Top 0.2%)27(Top 0.5%)
24M24.00 mi1.00 mi147+18126+17126+1727(Top 0.1%)21(Top 0.1%)21(Top 0.4%)
40K24.85 mi0.85 mi132+15112+14112+1424(Top 0.09%)19(Top 0.1%)19(Top 0.4%)
25.2M25.20 mi0.35 mi131+1111+1111+121(Top 0.08%)17(Top 0.1%)17(Top 0.3%)
Finish26.22 mi1.02 mi117+1498+1398+1314(Top 0.05%)13(Top 0.09%)13(Top 0.2%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 0.9%
×21stories
+97ft-345ft

Overall

233

Males

204

M18-39

204

5K→10K

3.1 - 6.2 mi

Top 1%
×5stories
+79ft-138ft

Overall

267

Males

237

M18-39

237

10K→15K

6.2 - 9.3 mi

Top 0.9%
×3stories
+67ft-78ft

Overall

233

Males

204

M18-39

204

15K→20K

9.3 - 12.4 mi

Top 0.9%
×5stories
+106ft-86ft

Overall

247

Males

220

M18-39

220

20K→Half

12.4 - 13.1 mi

Top 0.7%
×2stories
+19ft-37ft

Overall

196

Males

174

M18-39

174

Half→25K

13.1 - 15.5 mi

Top 0.8%
×4stories
+66ft-88ft

Overall

215

Males

192

M18-39

192

25K→30K

15.5 - 18.6 mi

Top 0.9%
×9stories
+181ft-148ft

Overall

230

Males

206

M18-39

206

30K→20M

18.6 - 20.0 mi

Top 0.6%
×5stories
+64ft-50ft

Overall

162

Males

140

M18-39

140

20M→21M

20.0 - 21.0 mi

Top 0.3%
×8stories
+106ft-24ft

Overall

70

Males

59

M18-39

59

21M→35K

21.0 - 21.8 mi

Top 0.2%
×7stories
+17ft-86ft

Overall

60

Males

46

M18-39

46

35K→23M

21.8 - 23.0 mi

Top 0.1%
×5stories
+23ft-63ft

Overall

34

Males

27

M18-39

27

23M→24M

23.0 - 24.0 mi

Top 0.1%
×6stories
+12ft-82ft

Overall

27

Males

21

M18-39

21

24M→40K

24.0 - 24.9 mi

Top 0.09%
×1story
+6ft-20ft

Overall

24

Males

19

M18-39

19

40K→25.2M

24.9 - 25.2 mi

Top 0.08%
×1story
+13ft-16ft

Overall

21

Males

17

M18-39

17

25.2M→Finish

25.2 - 26.2 mi

Top 0.05%
×2stories
+22ft-21ft

Overall

14

Males

13

M18-39

13

Passing Analysis

Category:
Athletes Passed
170
Passed By
73
Net Change
+97
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#214
5K → 10K1041-31#214#245
10K → 15K158+7#245#238
15K → 20K513-8#238#246
20K → Half220#246#246
Half → 25K164+12#246#234
25K → 30K134+9#234#225
30K → 20M191+18#225#207
20M → 21M180+18#207#189
21M → 35K50+5#189#184
35K → 23M190+19#184#165
23M → 24M180+18#165#147
24M → 40K150+15#147#132
40K → 25.2M10+1#132#131
25.2M → Finish140+14#131#117
TOTALS17073+97
📊

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