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BOSTON MARATHON 2023

Carl Underhill

Bib: 24754•M

MA

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
28:33
Rank: #21181
Start → 5K
28:33 | 9:11/mi
10K· 6.21 mi
56:07
Rank: #20769 (+412)
5K → 10K
27:34 | 8:52/mi
15K· 9.32 mi
1:25:05
Rank: #21136 (-367)
10K → 15K
28:58 | 9:19/mi
20K· 12.43 mi
1:53:04
Rank: #20773 (+363)
15K → 20K
27:59 | 9:00/mi
Half· 13.11 mi
1:59:18
Rank: #20779 (-6)
20K → Half
6:14 | 9:08/mi
25K· 15.53 mi
2:21:48
Rank: #20676 (+103)
Half → 25K
22:30 | 9:17/mi
30K· 18.64 mi
2:51:11
Rank: #20393 (+283)
25K → 30K
29:23 | 9:27/mi
20M
3:03:49
Rank: #20217 (+176)
30K → 20M
12:38 | 9:18/mi
21M
3:13:42
Rank: #20044 (+173)
20M → 21M
9:53 | 9:53/mi
35K· 21.75 mi
3:20:28
Rank: #19967 (+77)
21M → 35K
6:46 | 9:03/mi
23M
3:32:06
Rank: #19816 (+151)
35K → 23M
11:38 | 9:17/mi
24M
3:41:03
Rank: #19701 (+115)
23M → 24M
8:57 | 8:57/mi
40K· 24.85 mi
3:48:40
Rank: #19572 (+129)
24M → 40K
7:37 | 8:54/mi
25.2M
3:51:44
Rank: #19490 (+82)
40K → 25.2M
3:04 | 8:54/mi
Finish· 26.22 mi
4:00:10
Rank: #19338 (+152)
25.2M → Finish
8:26 | 8:17/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:59:18
Pace9:06 /mi
2nd Half
Distance13.11 mi
Time2:00:52
Pace9:13 /mi
📊Positive Split: 1.3% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi11:49:2828:339:1128:33
9:11
-
10K
6.21 mi12:17:0256:079:0227:34
8:52
-0:19
15K
9.32 mi12:46:001:25:059:0828:58
9:19
+0:27
20K
12.43 mi13:13:591:53:049:0627:59
9:00
-0:19
Half
13.11 mi13:20:131:59:189:066:14
9:08
+0:08
25K
15.53 mi13:42:432:21:489:0822:30
9:17
+0:09
30K
18.64 mi14:12:062:51:119:1129:23
9:27
+0:10
20M
20.00 mi14:24:443:03:499:1112:38
9:18
-0:09
21M
21.00 mi14:34:373:13:429:139:53
9:53
+0:35
35K
21.75 mi14:41:233:20:289:136:46
9:03
-0:50
23M
23.00 mi14:53:013:32:069:1311:38
9:17
+0:14
24M
24.00 mi15:01:583:41:039:138:57
8:57
-0:20
40K
24.85 mi15:09:353:48:409:127:37
8:54
-0:03
25.2M
25.20 mi15:12:393:51:449:123:04
8:54
0:00
Finish
26.22 mi15:21:054:00:109:108:26
8:17
-0:37

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

8:17 /mi

Average Pace

9:10 /mi

Slowest Pace

9:53 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

1:30:23

38% of race

Time at Steady Pace

2:19:54

58% of race

Time at Slower Pace

9:53

4% of race

Average Pace: 9:10 /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 mi11:49:2828:339:1128:33
9:11
#21181
10K
6.21 mi12:17:0256:079:0227:34
8:52
#20769
15K
9.32 mi12:46:001:25:059:0828:58
9:19
#21136
20K
12.43 mi13:13:591:53:049:0627:59
9:00
#20773
Half
13.11 mi13:20:131:59:189:066:14
9:08
#20779
25K
15.53 mi13:42:432:21:489:0822:30
9:17
#20676
30K
18.64 mi14:12:062:51:119:1129:23
9:27
#20393
20M
20.00 mi14:24:443:03:499:1112:38
9:18
#20217
21M
21.00 mi14:34:373:13:429:139:53
9:53
#20044
35K
21.75 mi14:41:233:20:289:136:46
9:03
#19967
23M
23.00 mi14:53:013:32:069:1311:38
9:17
#19816
24M
24.00 mi15:01:583:41:039:138:57
8:57
#19701
40K
24.85 mi15:09:353:48:409:127:37
8:54
#19572
25.2M
25.20 mi15:12:393:51:449:123:04
8:54
#19490
Finish
26.22 mi15:21:054:00:109:108:26
8:17
#19338
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM18-39Seg. OverallSeg. MalesSeg. M18-39
5K3.11 mi3.11 mi21181126961269621707(Top 82%)13067(Top 86%)13067(Top 247%)
10K6.21 mi3.10 mi20769+41212566+13012566+13020291(Top 76%)12403(Top 82%)12403(Top 235%)
15K9.32 mi3.11 mi21136-36712762-19612762-19621707(Top 82%)13067(Top 86%)13067(Top 247%)
20K12.43 mi3.11 mi20773+36312605+15712605+15719728(Top 74%)12197(Top 80%)12197(Top 231%)
Half13.11 mi0.68 mi20779-612608-312608-320923(Top 79%)12691(Top 84%)12691(Top 240%)
25K15.53 mi2.42 mi20676+10312571+3712571+3720128(Top 76%)12336(Top 81%)12336(Top 233%)
30K18.64 mi3.11 mi20393+28312426+14512426+14519272(Top 72%)11911(Top 78%)11911(Top 225%)
20M20.00 mi1.36 mi20217+17612329+9712329+9718007(Top 68%)11242(Top 74%)11242(Top 213%)
21M21.00 mi1.00 mi20044+17312252+7712252+7717575(Top 66%)11049(Top 73%)11049(Top 209%)
35K21.75 mi0.75 mi19967+7712214+3812214+3818078(Top 68%)11180(Top 74%)11180(Top 212%)
23M23.00 mi1.25 mi19816+15112138+7612138+7617473(Top 66%)10906(Top 72%)10906(Top 206%)
24M24.00 mi1.00 mi19701+11512086+5212086+5216992(Top 64%)10628(Top 70%)10628(Top 201%)
40K24.85 mi0.85 mi19572+12912024+6212024+6215662(Top 59%)9988(Top 66%)9988(Top 189%)
25.2M25.20 mi0.35 mi19490+8211981+4311981+4311904(Top 45%)8247(Top 54%)8247(Top 156%)
Finish26.22 mi1.02 mi19338+15211916+6511916+6513945(Top 52%)9232(Top 61%)9232(Top 175%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 82%
×21stories
+97ft-345ft

Overall

21707

Males

13067

M18-39

13067

5K→10K

3.1 - 6.2 mi

Top 76%
×5stories
+79ft-138ft

Overall

20291

Males

12403

M18-39

12403

10K→15K

6.2 - 9.3 mi

Top 82%
×3stories
+67ft-78ft

Overall

21707

Males

13067

M18-39

13067

15K→20K

9.3 - 12.4 mi

Top 74%
×5stories
+106ft-86ft

Overall

19728

Males

12197

M18-39

12197

20K→Half

12.4 - 13.1 mi

Top 79%
×2stories
+19ft-37ft

Overall

20923

Males

12691

M18-39

12691

Half→25K

13.1 - 15.5 mi

Top 76%
×4stories
+66ft-88ft

Overall

20128

Males

12336

M18-39

12336

25K→30K

15.5 - 18.6 mi

Top 72%
×9stories
+181ft-148ft

Overall

19272

Males

11911

M18-39

11911

30K→20M

18.6 - 20.0 mi

Top 68%
×5stories
+64ft-50ft

Overall

18007

Males

11242

M18-39

11242

20M→21M

20.0 - 21.0 mi

Top 66%
×8stories
+106ft-24ft

Overall

17575

Males

11049

M18-39

11049

21M→35K

21.0 - 21.8 mi

Top 68%
×7stories
+17ft-86ft

Overall

18078

Males

11180

M18-39

11180

35K→23M

21.8 - 23.0 mi

Top 66%
×5stories
+23ft-63ft

Overall

17473

Males

10906

M18-39

10906

23M→24M

23.0 - 24.0 mi

Top 64%
×6stories
+12ft-82ft

Overall

16992

Males

10628

M18-39

10628

24M→40K

24.0 - 24.9 mi

Top 59%
×1story
+6ft-20ft

Overall

15662

Males

9988

M18-39

9988

40K→25.2M

24.9 - 25.2 mi

Top 45%
×1story
+13ft-16ft

Overall

11904

Males

8247

M18-39

8247

25.2M→Finish

25.2 - 26.2 mi

Top 52%
×2stories
+22ft-21ft

Overall

13945

Males

9232

M18-39

9232

Passing Analysis

Category:
Athletes Passed
2583
Passed By
740
Net Change
+1843
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#21181
5K → 10K538126+412#21181#20769
10K → 15K55422-367#20769#21136
15K → 20K38825+363#21136#20773
20K → Half2834-6#20773#20779
Half → 25K15956+103#20779#20676
25K → 30K30522+283#20676#20393
30K → 20M18610+176#20393#20217
20M → 21M18411+173#20217#20044
21M → 35K847+77#20044#19967
35K → 23M16817+151#19967#19816
23M → 24M1183+115#19816#19701
24M → 40K1312+129#19701#19572
40K → 25.2M842+82#19572#19490
25.2M → Finish1553+152#19490#19338
TOTALS2583740+1843
📊

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