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BOSTON MARATHON 2023

Stefan Kemp

Bib: 5513•M

0:00
0:00
/ mi
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Overall
#0 / 26622
Top 45%
Gender (Male)
#0 / 15176
Division (M18-39)
#0 / 5285
Race Day Weather
49°/39°F
light intensity drizzle

⏱️ Race Timeline

Course Elevation
7–469 ft
≈
×2stacked redwood trees
•▲ 890 ft climb · ▼ 1342 ft descent
Ribbon color based on
FasterSteadySlower· vs. your average pace
Start
0:00
Race begins
5K· 3.11 mi
7:42/mi
23:55
↑ 97↓ 3451.5%
10K· 6.21 mi
7:49/mi
48:11
↑ 79↓ 1380.4%
15K· 9.32 mi
7:59/mi
1:13:00
↑ 67↓ 78
20K· 12.43 mi
7:48/mi
1:37:15
↑ 106↓ 860.1%
Half· 13.11 mi
7:20/mi
1:42:15
↑ 19↓ 370.5%
25K· 15.53 mi
7:52/mi
2:01:19
↑ 66↓ 880.2%
30K· 18.64 mi
8:02/mi
2:26:18
↑ 181↓ 1480.2%
20M
8:00/mi
2:37:10
↑ 64↓ 500.2%
21M
8:26/mi
2:45:36
↑ 106↓ 241.6%
35K· 21.75 mi
7:34/mi
2:51:16
↑ 17↓ 861.7%
23M
8:12/mi
3:01:32
↑ 23↓ 630.6%
24M
8:30/mi
3:10:02
↓ 821.3%
40K· 24.85 mi
8:46/mi
3:17:32
↓ 200.3%
25.2M
9:37/mi
3:20:51
↑ 13↓ 160.2%
Finish· 26.22 mi
8:23/mi
3:29:24
↑ 22↓ 21

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:42:15
Pace7:48 /mi
2nd Half
Distance13.11 mi
Time1:47:09
Pace8:10 /mi
📊Positive Split: 4.8% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:28:3123:557:4223:55
7:42
-
10K
6.21 mi10:52:4748:117:4524:16
7:49
+0:07
15K
9.32 mi11:17:361:13:007:5024:49
7:59
+0:10
20K
12.43 mi11:41:511:37:157:5024:15
7:48
-0:11
Half
13.11 mi11:46:511:42:157:485:00
7:20
-0:28
25K
15.53 mi12:05:552:01:197:4919:04
7:52
+0:32
30K
18.64 mi12:30:542:26:187:5124:59
8:02
+0:10
20M
20.00 mi12:41:462:37:107:5110:52
8:00
-0:02
21M
21.00 mi12:50:122:45:367:538:26
8:26
+0:26
35K
21.75 mi12:55:522:51:167:535:40
7:34
-0:52
23M
23.00 mi13:06:083:01:327:5410:16
8:12
+0:38
24M
24.00 mi13:14:383:10:027:558:30
8:30
+0:18
40K
24.85 mi13:22:083:17:327:577:30
8:46
+0:16
25.2M
25.20 mi13:25:273:20:517:583:19
9:37
+0:51
Finish
26.22 mi13:34:003:29:248:008:33
8:23
-1:14

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

7:20 /mi

Average Pace

8:00 /mi

Slowest Pace

9:37 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

34:35

17% of race

Time at Steady Pace

2:18:31

66% of race

Time at Slower Pace

36:18

17% of race

Average Pace: 7:59 /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 mi10:28:3123:557:4223:55
7:42
#11417
10K
6.21 mi10:52:4748:117:4524:16
7:49
#12304
15K
9.32 mi11:17:361:13:007:5024:49
7:59
#12974
20K
12.43 mi11:41:511:37:157:5024:15
7:48
#12621
Half
13.11 mi11:46:511:42:157:485:00
7:20
#12398
25K
15.53 mi12:05:552:01:197:4919:04
7:52
#12265
30K
18.64 mi12:30:542:26:187:5124:59
8:02
#12018
20M
20.00 mi12:41:462:37:107:5110:52
8:00
#11839
21M
21.00 mi12:50:122:45:367:538:26
8:26
#11735
35K
21.75 mi12:55:522:51:167:535:40
7:34
#11633
23M
23.00 mi13:06:083:01:327:5410:16
8:12
#11583
24M
24.00 mi13:14:383:10:027:558:30
8:30
#11731
40K
24.85 mi13:22:083:17:327:577:30
8:46
#11862
25.2M
25.20 mi13:25:273:20:517:583:19
9:37
#11949
Finish
26.22 mi13:34:003:29:248:008:33
8:23
#12075
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM18-39Seg. OverallSeg. MalesSeg. M18-39
5K3.11 mi3.11 mi114178857885714267(Top 54%)10007(Top 66%)10007(Top 189%)
10K6.21 mi3.10 mi12304-8879248-3919248-39113206(Top 50%)9633(Top 63%)9633(Top 182%)
15K9.32 mi3.11 mi12974-6709513-2659513-26514267(Top 54%)10007(Top 66%)10007(Top 189%)
20K12.43 mi3.11 mi12621+3539335+1789335+17811778(Top 44%)8925(Top 59%)8925(Top 169%)
Half13.11 mi0.68 mi12398+2239234+1019234+1018835(Top 33%)7426(Top 49%)7426(Top 141%)
25K15.53 mi2.42 mi12265+1339154+809154+8011632(Top 44%)8767(Top 58%)8767(Top 166%)
30K18.64 mi3.11 mi12018+2479017+1379017+13711226(Top 42%)8464(Top 56%)8464(Top 160%)
20M20.00 mi1.36 mi11839+1798919+988919+9810235(Top 38%)7888(Top 52%)7888(Top 149%)
21M21.00 mi1.00 mi11735+1048856+638856+6310069(Top 38%)7648(Top 50%)7648(Top 145%)
35K21.75 mi0.75 mi11633+1028803+538803+539095(Top 34%)7138(Top 47%)7138(Top 135%)
23M23.00 mi1.25 mi11583+508749+548749+5411180(Top 42%)8063(Top 53%)8063(Top 153%)
24M24.00 mi1.00 mi11731-1488803-548803-5414447(Top 54%)9500(Top 63%)9500(Top 180%)
40K24.85 mi0.85 mi11862-1318832-298832-2914897(Top 56%)9631(Top 63%)9631(Top 182%)
25.2M25.20 mi0.35 mi11949-878859-278859-2715661(Top 59%)9949(Top 66%)9949(Top 188%)
Finish26.22 mi1.02 mi12075-1268890-318890-3114636(Top 55%)9547(Top 63%)9547(Top 181%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 54%
×21story building
+97ft-345ft

Overall

14267

Males

10007

M18-39

10007

5K→10K

3.1 - 6.2 mi

Top 50%
×5story building
+79ft-138ft

Overall

13206

Males

9633

M18-39

9633

10K→15K

6.2 - 9.3 mi

Top 54%
×3story building
+67ft-78ft

Overall

14267

Males

10007

M18-39

10007

15K→20K

9.3 - 12.4 mi

Top 44%
×5story building
+106ft-86ft

Overall

11778

Males

8925

M18-39

8925

20K→Half

12.4 - 13.1 mi

Top 33%
×2story building
+19ft-37ft

Overall

8835

Males

7426

M18-39

7426

Half→25K

13.1 - 15.5 mi

Top 44%
×4story building
+66ft-88ft

Overall

11632

Males

8767

M18-39

8767

25K→30K

15.5 - 18.6 mi

Top 42%
×9story building
+181ft-148ft

Overall

11226

Males

8464

M18-39

8464

30K→20M

18.6 - 20.0 mi

Top 38%
×5story building
+64ft-50ft

Overall

10235

Males

7888

M18-39

7888

20M→21M

20.0 - 21.0 mi

Top 38%
×8story building
+106ft-24ft

Overall

10069

Males

7648

M18-39

7648

21M→35K

21.0 - 21.8 mi

Top 34%
×7story building
+17ft-86ft

Overall

9095

Males

7138

M18-39

7138

35K→23M

21.8 - 23.0 mi

Top 42%
×5story building
+23ft-63ft

Overall

11180

Males

8063

M18-39

8063

23M→24M

23.0 - 24.0 mi

Top 54%
×6story building
+12ft-82ft

Overall

14447

Males

9500

M18-39

9500

24M→40K

24.0 - 24.9 mi

Top 56%
×1story
+6ft-20ft

Overall

14897

Males

9631

M18-39

9631

40K→25.2M

24.9 - 25.2 mi

Top 59%
×1story
+13ft-16ft

Overall

15661

Males

9949

M18-39

9949

25.2M→Finish

25.2 - 26.2 mi

Top 55%
×2story building
+22ft-21ft

Overall

14636

Males

9547

M18-39

9547

Passing Analysis

Category:
Athletes Passed
1943
Passed By
2601
Net Change
-658
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#11417
5K → 10K73960-887#11417#12304
10K → 15K42712-670#12304#12974
15K → 20K40148+353#12974#12621
20K → Half2230+223#12621#12398
Half → 25K18855+133#12398#12265
25K → 30K32679+247#12265#12018
30K → 20M20526+179#12018#11839
20M → 21M14339+104#11839#11735
21M → 35K1119+102#11735#11633
35K → 23M12070+50#11633#11583
23M → 24M28176-148#11583#11731
24M → 40K36167-131#11731#11862
40K → 25.2M996-87#11862#11949
25.2M → Finish38164-126#11949#12075
TOTALS19432601-658
📊

Passing Visuals

Category:
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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