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BOSTON MARATHON 2023

Kathryn Seyfarth

Bib: 10303•F

MA

0:00
0:00
/ mi
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Overall
#0 / 26622
Top 30%
Gender (Female)
#0 / 11423
Top 11%
Division (F18-39)
#0 / 4884
Top 20%
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
7:30/mi
23:18
↑ 97↓ 3451.5%
10K· 6.21 mi
7:18/mi
46:00
↑ 79↓ 1380.4%
15K· 9.32 mi
7:23/mi
1:08:57
↑ 67↓ 78
20K· 12.43 mi
7:22/mi
1:31:50
↑ 106↓ 860.1%
Half· 13.11 mi
7:18/mi
1:36:49
↑ 19↓ 370.5%
25K· 15.53 mi
7:39/mi
1:55:22
↑ 66↓ 880.2%
30K· 18.64 mi
7:34/mi
2:18:52
↑ 181↓ 1480.2%
20M
7:30/mi
2:29:03
↑ 64↓ 500.2%
21M
7:52/mi
2:36:55
↑ 106↓ 241.6%
35K· 21.75 mi
7:09/mi
2:42:16
↑ 17↓ 861.7%
23M
7:36/mi
2:51:47
↑ 23↓ 630.6%
24M
7:21/mi
2:59:08
↓ 821.3%
40K· 24.85 mi
7:23/mi
3:05:27
↓ 200.3%
25.2M
7:56/mi
3:08:11
↑ 13↓ 160.2%
Finish· 26.22 mi
7:15/mi
3:15:34
↑ 22↓ 21

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:36:49
Pace7:23 /mi
2nd Half
Distance13.11 mi
Time1:38:45
Pace7:32 /mi
📊Positive Split: 2.0% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:49:2323:187:3023:18
7:30
-
10K
6.21 mi11:12:0546:007:2422:42
7:18
-0:12
15K
9.32 mi11:35:021:08:577:2422:57
7:23
+0:05
20K
12.43 mi11:57:551:31:507:2322:53
7:22
-0:01
Half
13.11 mi12:02:541:36:497:234:59
7:18
-0:04
25K
15.53 mi12:21:271:55:227:2618:33
7:39
+0:21
30K
18.64 mi12:44:572:18:527:2723:30
7:34
-0:05
20M
20.00 mi12:55:082:29:037:2710:11
7:30
-0:04
21M
21.00 mi13:03:002:36:557:287:52
7:52
+0:22
35K
21.75 mi13:08:212:42:167:285:21
7:09
-0:43
23M
23.00 mi13:17:522:51:477:289:31
7:36
+0:27
24M
24.00 mi13:25:132:59:087:287:21
7:21
-0:15
40K
24.85 mi13:31:323:05:277:286:19
7:23
+0:02
25.2M
25.20 mi13:34:163:08:117:282:44
7:56
+0:33
Finish
26.22 mi13:41:393:15:347:287:23
7:15
-0:41

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

7:09 /mi

Average Pace

7:28 /mi

Slowest Pace

7:56 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

3:04:58

95% of race

Time at Steady Pace

10:36

5% of race

Time at Slower Pace

0:00

0% of race

Average Pace: 7:28 /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 mi10:49:2323:187:3023:18
7:30
#9643
10K
6.21 mi11:12:0546:007:2422:42
7:18
#9208
15K
9.32 mi11:35:021:08:577:2422:57
7:23
#9168
20K
12.43 mi11:57:551:31:507:2322:53
7:22
#8919
Half
13.11 mi12:02:541:36:497:234:59
7:18
#8893
25K
15.53 mi12:21:271:55:227:2618:33
7:39
#9034
30K
18.64 mi12:44:572:18:527:2723:30
7:34
#8747
20M
20.00 mi12:55:082:29:037:2710:11
7:30
#8578
21M
21.00 mi13:03:002:36:557:287:52
7:52
#8443
35K
21.75 mi13:08:212:42:167:285:21
7:09
#8344
23M
23.00 mi13:17:522:51:477:289:31
7:36
#8212
24M
24.00 mi13:25:132:59:087:287:21
7:21
#8115
40K
24.85 mi13:31:323:05:277:286:19
7:23
#7990
25.2M
25.20 mi13:34:163:08:117:282:44
7:56
#7957
Finish
26.22 mi13:41:393:15:347:287:23
7:15
#7892
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallFemalesF18-39Seg. OverallSeg. FemalesSeg. F18-39
5K3.11 mi3.11 mi9643167716779237(Top 35%)1532(Top 13%)1532(Top 31%)
10K6.21 mi3.10 mi9208+4351500+1771500+1778907(Top 33%)1371(Top 12%)1371(Top 28%)
15K9.32 mi3.11 mi9168+401485+151485+159237(Top 35%)1532(Top 13%)1532(Top 31%)
20K12.43 mi3.11 mi8919+2491405+801405+808272(Top 31%)1207(Top 11%)1207(Top 25%)
Half13.11 mi0.68 mi8893+261397+81397+88688(Top 33%)1348(Top 12%)1348(Top 28%)
25K15.53 mi2.42 mi9034-1411457-601457-609917(Top 37%)1963(Top 17%)1963(Top 40%)
30K18.64 mi3.11 mi8747+2871386+711386+717685(Top 29%)1175(Top 10%)1175(Top 24%)
20M20.00 mi1.36 mi8578+1691347+391347+396770(Top 25%)949(Top 8%)949(Top 19%)
21M21.00 mi1.00 mi8443+1351318+291318+296574(Top 25%)971(Top 9%)971(Top 20%)
35K21.75 mi0.75 mi8344+991289+291289+296275(Top 24%)856(Top 7%)856(Top 18%)
23M23.00 mi1.25 mi8212+1321260+291260+297117(Top 27%)1214(Top 11%)1214(Top 25%)
24M24.00 mi1.00 mi8115+971246+141246+146749(Top 25%)1171(Top 10%)1171(Top 24%)
40K24.85 mi0.85 mi7990+1251218+281218+286042(Top 23%)1000(Top 9%)1000(Top 20%)
25.2M25.20 mi0.35 mi7957+331215+31215+36160(Top 23%)1110(Top 10%)1110(Top 23%)
Finish26.22 mi1.02 mi7892+65121512156751(Top 25%)1328(Top 12%)1328(Top 27%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 35%
×21story building
+97ft-345ft

Overall

9237

Females

1532

F18-39

1532

5K→10K

3.1 - 6.2 mi

Top 33%
×5story building
+79ft-138ft

Overall

8907

Females

1371

F18-39

1371

10K→15K

6.2 - 9.3 mi

Top 35%
×3story building
+67ft-78ft

Overall

9237

Females

1532

F18-39

1532

15K→20K

9.3 - 12.4 mi

Top 31%
×5story building
+106ft-86ft

Overall

8272

Females

1207

F18-39

1207

20K→Half

12.4 - 13.1 mi

Top 33%
×2story building
+19ft-37ft

Overall

8688

Females

1348

F18-39

1348

Half→25K

13.1 - 15.5 mi

Top 37%
×4story building
+66ft-88ft

Overall

9917

Females

1963

F18-39

1963

25K→30K

15.5 - 18.6 mi

Top 29%
×9story building
+181ft-148ft

Overall

7685

Females

1175

F18-39

1175

30K→20M

18.6 - 20.0 mi

Top 25%
×5story building
+64ft-50ft

Overall

6770

Females

949

F18-39

949

20M→21M

20.0 - 21.0 mi

Top 25%
×8story building
+106ft-24ft

Overall

6574

Females

971

F18-39

971

21M→35K

21.0 - 21.8 mi

Top 24%
×7story building
+17ft-86ft

Overall

6275

Females

856

F18-39

856

35K→23M

21.8 - 23.0 mi

Top 27%
×5story building
+23ft-63ft

Overall

7117

Females

1214

F18-39

1214

23M→24M

23.0 - 24.0 mi

Top 25%
×6story building
+12ft-82ft

Overall

6749

Females

1171

F18-39

1171

24M→40K

24.0 - 24.9 mi

Top 23%
×1story
+6ft-20ft

Overall

6042

Females

1000

F18-39

1000

40K→25.2M

24.9 - 25.2 mi

Top 23%
×1story
+13ft-16ft

Overall

6160

Females

1110

F18-39

1110

25.2M→Finish

25.2 - 26.2 mi

Top 25%
×2story building
+22ft-21ft

Overall

6751

Females

1328

F18-39

1328

Passing Analysis

Category:
Athletes Passed
2412
Passed By
661
Net Change
+1751
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#9643
5K → 10K552117+435#9643#9208
10K → 15K173133+40#9208#9168
15K → 20K27930+249#9168#8919
20K → Half3812+26#8919#8893
Half → 25K71212-141#8893#9034
25K → 30K32235+287#9034#8747
30K → 20M1789+169#8747#8578
20M → 21M14914+135#8578#8443
21M → 35K1078+99#8443#8344
35K → 23M15927+132#8344#8212
23M → 24M11518+97#8212#8115
24M → 40K1327+125#8115#7990
40K → 25.2M4512+33#7990#7957
25.2M → Finish9227+65#7957#7892
TOTALS2412661+1751
📊

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