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BOSTON MARATHON 2023

Brian Kosewic

Bib: 2907•M

CA

0:00
0:00
/ mi
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Overall
#0 / 26622
Top 5%
Gender (Male)
#0 / 15176
Top 8%
Division (M18-39)
#0 / 5285
Top 20%
Race Day Weather
49°/39°F
light intensity drizzle

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
19:41
Rank: #1585
Start → 5K
19:41 | 6:20/mi
10K· 6.21 mi
38:53
Rank: #1406 (+179)
5K → 10K
19:12 | 6:11/mi
15K· 9.32 mi
58:06
Rank: #1303 (+103)
10K → 15K
19:13 | 6:11/mi
20K· 12.43 mi
1:17:21
Rank: #1218 (+85)
15K → 20K
19:15 | 6:12/mi
Half· 13.11 mi
1:21:30
Rank: #1208 (+10)
20K → Half
4:09 | 6:05/mi
25K· 15.53 mi
1:36:40
Rank: #1193 (+15)
Half → 25K
15:10 | 6:15/mi
30K· 18.64 mi
1:56:21
Rank: #1145 (+48)
25K → 30K
19:41 | 6:20/mi
20M
2:05:02
Rank: #1130 (+15)
30K → 20M
8:41 | 6:23/mi
21M
2:11:49
Rank: #1117 (+13)
20M → 21M
6:47 | 6:47/mi
35K· 21.75 mi
2:16:49
Rank: #1162 (-45)
21M → 35K
5:00 | 6:41/mi
23M
2:25:21
Rank: #1215 (-53)
35K → 23M
8:32 | 6:49/mi
24M
2:31:43
Rank: #1211 (+4)
23M → 24M
6:22 | 6:22/mi
40K· 24.85 mi
2:37:34
Rank: #1256 (-45)
24M → 40K
5:51 | 6:51/mi
25.2M
2:40:07
Rank: #1272 (-16)
40K → 25.2M
2:33 | 7:24/mi
Finish· 26.22 mi
2:47:03
Rank: #1333 (-61)
25.2M → Finish
6:56 | 6:48/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:21:30
Pace6:13 /mi
2nd Half
Distance13.11 mi
Time1:25:33
Pace6:32 /mi
📊Positive Split: 5.0% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:20:3019:416:2019:41
6:20
-
10K
6.21 mi10:39:4238:536:1519:12
6:11
-0:09
15K
9.32 mi10:58:5558:066:1419:13
6:11
0:00
20K
12.43 mi11:18:101:17:216:1319:15
6:12
+0:01
Half
13.11 mi11:22:191:21:306:134:09
6:05
-0:07
25K
15.53 mi11:37:291:36:406:1315:10
6:15
+0:10
30K
18.64 mi11:57:101:56:216:1419:41
6:20
+0:05
20M
20.00 mi12:05:512:05:026:158:41
6:23
+0:03
21M
21.00 mi12:12:382:11:496:176:47
6:47
+0:24
35K
21.75 mi12:17:382:16:496:175:00
6:41
-0:06
23M
23.00 mi12:26:102:25:216:198:32
6:49
+0:08
24M
24.00 mi12:32:322:31:436:196:22
6:22
-0:27
40K
24.85 mi12:38:232:37:346:205:51
6:51
+0:29
25.2M
25.20 mi12:40:562:40:076:212:33
7:24
+0:33
Finish
26.22 mi12:47:522:47:036:236:56
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

6:05 /mi

Average Pace

6:23 /mi

Slowest Pace

7:24 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

42:34

25% of race

Time at Steady Pace

1:28:50

53% of race

Time at Slower Pace

35:39

21% of race

Average Pace: 6:22 /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 mi10:20:3019:416:2019:41
6:20
#1585
10K
6.21 mi10:39:4238:536:1519:12
6:11
#1406
15K
9.32 mi10:58:5558:066:1419:13
6:11
#1303
20K
12.43 mi11:18:101:17:216:1319:15
6:12
#1218
Half
13.11 mi11:22:191:21:306:134:09
6:05
#1208
25K
15.53 mi11:37:291:36:406:1315:10
6:15
#1193
30K
18.64 mi11:57:101:56:216:1419:41
6:20
#1145
20M
20.00 mi12:05:512:05:026:158:41
6:23
#1130
21M
21.00 mi12:12:382:11:496:176:47
6:47
#1117
35K
21.75 mi12:17:382:16:496:175:00
6:41
#1162
23M
23.00 mi12:26:102:25:216:198:32
6:49
#1215
24M
24.00 mi12:32:322:31:436:196:22
6:22
#1211
40K
24.85 mi12:38:232:37:346:205:51
6:51
#1256
25.2M
25.20 mi12:40:562:40:076:212:33
7:24
#1272
Finish
26.22 mi12:47:522:47:036:236:56
6:48
#1333
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM18-39Seg. OverallSeg. MalesSeg. M18-39
5K3.11 mi3.11 mi1585151015101202(Top 5%)1145(Top 8%)1145(Top 22%)
10K6.21 mi3.10 mi1406+1791340+1701340+1701277(Top 5%)1214(Top 8%)1214(Top 23%)
15K9.32 mi3.11 mi1303+1031240+1001240+1001202(Top 5%)1145(Top 8%)1145(Top 22%)
20K12.43 mi3.11 mi1218+851160+801160+801050(Top 4%)1000(Top 7%)1000(Top 19%)
Half13.11 mi0.68 mi1208+101150+101150+101002(Top 4%)954(Top 6%)954(Top 18%)
25K15.53 mi2.42 mi1193+151138+121138+121178(Top 4%)1124(Top 7%)1124(Top 21%)
30K18.64 mi3.11 mi1145+481092+461092+461027(Top 4%)976(Top 6%)976(Top 18%)
20M20.00 mi1.36 mi1130+151077+151077+151131(Top 4%)1081(Top 7%)1081(Top 20%)
21M21.00 mi1.00 mi1117+131064+131064+131374(Top 5%)1310(Top 9%)1310(Top 25%)
35K21.75 mi0.75 mi1162-451108-441108-443532(Top 13%)3267(Top 22%)3267(Top 62%)
23M23.00 mi1.25 mi1215-531160-521160-522777(Top 10%)2593(Top 17%)2593(Top 49%)
24M24.00 mi1.00 mi1211+41155+51155+51600(Top 6%)1513(Top 10%)1513(Top 29%)
40K24.85 mi0.85 mi1256-451198-431198-433067(Top 12%)2812(Top 19%)2812(Top 53%)
25.2M25.20 mi0.35 mi1272-161212-141212-143503(Top 13%)3135(Top 21%)3135(Top 59%)
Finish26.22 mi1.02 mi1333-611269-571269-574128(Top 16%)3632(Top 24%)3632(Top 69%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 5%
×21stories
+97ft-345ft

Overall

1202

Males

1145

M18-39

1145

5K→10K

3.1 - 6.2 mi

Top 5%
×5stories
+79ft-138ft

Overall

1277

Males

1214

M18-39

1214

10K→15K

6.2 - 9.3 mi

Top 5%
×3stories
+67ft-78ft

Overall

1202

Males

1145

M18-39

1145

15K→20K

9.3 - 12.4 mi

Top 4%
×5stories
+106ft-86ft

Overall

1050

Males

1000

M18-39

1000

20K→Half

12.4 - 13.1 mi

Top 4%
×2stories
+19ft-37ft

Overall

1002

Males

954

M18-39

954

Half→25K

13.1 - 15.5 mi

Top 4%
×4stories
+66ft-88ft

Overall

1178

Males

1124

M18-39

1124

25K→30K

15.5 - 18.6 mi

Top 4%
×9stories
+181ft-148ft

Overall

1027

Males

976

M18-39

976

30K→20M

18.6 - 20.0 mi

Top 4%
×5stories
+64ft-50ft

Overall

1131

Males

1081

M18-39

1081

20M→21M

20.0 - 21.0 mi

Top 5%
×8stories
+106ft-24ft

Overall

1374

Males

1310

M18-39

1310

21M→35K

21.0 - 21.8 mi

Top 13%
×7stories
+17ft-86ft

Overall

3532

Males

3267

M18-39

3267

35K→23M

21.8 - 23.0 mi

Top 10%
×5stories
+23ft-63ft

Overall

2777

Males

2593

M18-39

2593

23M→24M

23.0 - 24.0 mi

Top 6%
×6stories
+12ft-82ft

Overall

1600

Males

1513

M18-39

1513

24M→40K

24.0 - 24.9 mi

Top 12%
×1story
+6ft-20ft

Overall

3067

Males

2812

M18-39

2812

40K→25.2M

24.9 - 25.2 mi

Top 13%
×1story
+13ft-16ft

Overall

3503

Males

3135

M18-39

3135

25.2M→Finish

25.2 - 26.2 mi

Top 16%
×2stories
+22ft-21ft

Overall

4128

Males

3632

M18-39

3632

Passing Analysis

Category:
Athletes Passed
621
Passed By
369
Net Change
+252
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#1585
5K → 10K20122+179#1585#1406
10K → 15K1107+103#1406#1303
15K → 20K938+85#1303#1218
20K → Half144+10#1218#1208
Half → 25K2813+15#1208#1193
25K → 30K6517+48#1193#1145
30K → 20M3015+15#1145#1130
20M → 21M2613+13#1130#1117
21M → 35K550-45#1117#1162
35K → 23M1366-53#1162#1215
23M → 24M1713+4#1215#1211
24M → 40K752-45#1211#1256
40K → 25.2M319-16#1256#1272
25.2M → Finish970-61#1272#1333
TOTALS621369+252
📊

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