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BOSTON MARATHON 2023

Chelsea Swift

Bib: 17895•F

PA

0:00
0:00
/ mi
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Overall
#0 / 26622
Gender (Female)
#0 / 11423
Division (F18-39)
#0 / 4884
Race Day Weather
49°/39°F
light intensity drizzle

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
27:53
Rank: #20341
Start → 5K
27:53 | 8:58/mi
10K· 6.21 mi
56:20
Rank: #20925 (-584)
5K → 10K
28:27 | 9:09/mi
15K· 9.32 mi
1:24:43
Rank: #20996 (-71)
10K → 15K
28:23 | 9:08/mi
20K· 12.43 mi
1:53:08
Rank: #20801 (+195)
15K → 20K
28:25 | 9:09/mi
Half· 13.11 mi
1:59:21
Rank: #20802 (-1)
20K → Half
6:13 | 9:07/mi
25K· 15.53 mi
2:21:33
Rank: #20612 (+190)
Half → 25K
22:12 | 9:09/mi
30K· 18.64 mi
2:51:46
Rank: #20509 (+103)
25K → 30K
30:13 | 9:44/mi
20M
3:06:48
Rank: #20741 (-232)
30K → 20M
15:02 | 11:04/mi
21M
3:16:52
Rank: #20592 (+149)
20M → 21M
10:04 | 10:04/mi
35K· 21.75 mi
3:24:13
Rank: #20602 (-10)
21M → 35K
7:21 | 9:49/mi
23M
3:37:08
Rank: #20593 (+9)
35K → 23M
12:55 | 10:19/mi
24M
3:47:38
Rank: #20686 (-93)
23M → 24M
10:30 | 10:30/mi
40K· 24.85 mi
3:56:26
Rank: #20675 (+11)
24M → 40K
8:48 | 10:18/mi
25.2M
4:00:10
Rank: #20667 (+8)
40K → 25.2M
3:44 | 10:50/mi
Finish· 26.22 mi
4:10:17
Rank: #20694 (-27)
25.2M → Finish
10:07 | 9:56/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:59:21
Pace9:06 /mi
2nd Half
Distance13.11 mi
Time2:10:56
Pace9:59 /mi
📊Positive Split: 9.7% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi11:21:1327:538:5827:53
8:58
-
10K
6.21 mi11:49:4056:209:0428:27
9:09
+0:11
15K
9.32 mi12:18:031:24:439:0528:23
9:08
-0:01
20K
12.43 mi12:46:281:53:089:0628:25
9:09
+0:01
Half
13.11 mi12:52:411:59:219:066:13
9:07
-0:02
25K
15.53 mi13:14:532:21:339:0722:12
9:09
+0:02
30K
18.64 mi13:45:062:51:469:1330:13
9:44
+0:35
20M
20.00 mi14:00:083:06:489:2015:02
11:04
+1:20
21M
21.00 mi14:10:123:16:529:2210:04
10:04
-1:00
35K
21.75 mi14:17:333:24:139:237:21
9:49
-0:15
23M
23.00 mi14:30:283:37:089:2612:55
10:19
+0:30
24M
24.00 mi14:40:583:47:389:2910:30
10:30
+0:11
40K
24.85 mi14:49:463:56:269:318:48
10:18
-0:12
25.2M
25.20 mi14:53:304:00:109:323:44
10:50
+0:32
Finish
26.22 mi15:03:374:10:179:3310:07
9:56
-0:54

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

8:58 /mi

Average Pace

9:33 /mi

Slowest Pace

11:04 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

2:21:33

57% of race

Time at Steady Pace

57:45

23% of race

Time at Slower Pace

50:59

20% of race

Average Pace: 9:33 /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 mi11:21:1327:538:5827:53
8:58
#20341
10K
6.21 mi11:49:4056:209:0428:27
9:09
#20925
15K
9.32 mi12:18:031:24:439:0528:23
9:08
#20996
20K
12.43 mi12:46:281:53:089:0628:25
9:09
#20801
Half
13.11 mi12:52:411:59:219:066:13
9:07
#20802
25K
15.53 mi13:14:532:21:339:0722:12
9:09
#20612
30K
18.64 mi13:45:062:51:469:1330:13
9:44
#20509
20M
20.00 mi14:00:083:06:489:2015:02
11:04
#20741
21M
21.00 mi14:10:123:16:529:2210:04
10:04
#20592
35K
21.75 mi14:17:333:24:139:237:21
9:49
#20602
23M
23.00 mi14:30:283:37:089:2612:55
10:19
#20593
24M
24.00 mi14:40:583:47:389:2910:30
10:30
#20686
40K
24.85 mi14:49:463:56:269:318:48
10:18
#20675
25.2M
25.20 mi14:53:304:00:109:323:44
10:50
#20667
Finish
26.22 mi15:03:374:10:179:3310:07
9:56
#20694
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallFemalesF18-39Seg. OverallSeg. FemalesSeg. F18-39
5K3.11 mi3.11 mi203418020802021096(Top 79%)8288(Top 73%)8288(Top 170%)
10K6.21 mi3.10 mi20925-5848282-2628282-26221493(Top 81%)8550(Top 75%)8550(Top 175%)
15K9.32 mi3.11 mi20996-718284-28284-221096(Top 79%)8288(Top 73%)8288(Top 170%)
20K12.43 mi3.11 mi20801+1958163+1218163+12120357(Top 76%)7878(Top 69%)7878(Top 161%)
Half13.11 mi0.68 mi20802-18162+18162+120896(Top 78%)8191(Top 72%)8191(Top 168%)
25K15.53 mi2.42 mi20612+1908046+1168046+11619666(Top 74%)7514(Top 66%)7514(Top 154%)
30K18.64 mi3.11 mi20509+1038013+338013+3320221(Top 76%)7895(Top 69%)7895(Top 162%)
20M20.00 mi1.36 mi20741-2328145-1328145-13222809(Top 86%)9411(Top 82%)9411(Top 193%)
21M21.00 mi1.00 mi20592+1498081+648081+6418294(Top 69%)6931(Top 61%)6931(Top 142%)
35K21.75 mi0.75 mi20602-108092-118092-1120839(Top 78%)8405(Top 74%)8405(Top 172%)
23M23.00 mi1.25 mi20593+98100-88100-820866(Top 78%)8444(Top 74%)8444(Top 173%)
24M24.00 mi1.00 mi20686-938169-698169-6922045(Top 83%)9121(Top 80%)9121(Top 187%)
40K24.85 mi0.85 mi20675+118174-58174-520733(Top 78%)8460(Top 74%)8460(Top 173%)
25.2M25.20 mi0.35 mi20667+88172+28172+220076(Top 75%)8107(Top 71%)8107(Top 166%)
Finish26.22 mi1.02 mi20694-278197-258197-2521564(Top 81%)8885(Top 78%)8885(Top 182%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 79%
×21stories
+97ft-345ft

Overall

21096

Females

8288

F18-39

8288

5K→10K

3.1 - 6.2 mi

Top 81%
×5stories
+79ft-138ft

Overall

21493

Females

8550

F18-39

8550

10K→15K

6.2 - 9.3 mi

Top 79%
×3stories
+67ft-78ft

Overall

21096

Females

8288

F18-39

8288

15K→20K

9.3 - 12.4 mi

Top 76%
×5stories
+106ft-86ft

Overall

20357

Females

7878

F18-39

7878

20K→Half

12.4 - 13.1 mi

Top 78%
×2stories
+19ft-37ft

Overall

20896

Females

8191

F18-39

8191

Half→25K

13.1 - 15.5 mi

Top 74%
×4stories
+66ft-88ft

Overall

19666

Females

7514

F18-39

7514

25K→30K

15.5 - 18.6 mi

Top 76%
×9stories
+181ft-148ft

Overall

20221

Females

7895

F18-39

7895

30K→20M

18.6 - 20.0 mi

Top 86%
×5stories
+64ft-50ft

Overall

22809

Females

9411

F18-39

9411

20M→21M

20.0 - 21.0 mi

Top 69%
×8stories
+106ft-24ft

Overall

18294

Females

6931

F18-39

6931

21M→35K

21.0 - 21.8 mi

Top 78%
×7stories
+17ft-86ft

Overall

20839

Females

8405

F18-39

8405

35K→23M

21.8 - 23.0 mi

Top 78%
×5stories
+23ft-63ft

Overall

20866

Females

8444

F18-39

8444

23M→24M

23.0 - 24.0 mi

Top 83%
×6stories
+12ft-82ft

Overall

22045

Females

9121

F18-39

9121

24M→40K

24.0 - 24.9 mi

Top 78%
×1story
+6ft-20ft

Overall

20733

Females

8460

F18-39

8460

40K→25.2M

24.9 - 25.2 mi

Top 75%
×1story
+13ft-16ft

Overall

20076

Females

8107

F18-39

8107

25.2M→Finish

25.2 - 26.2 mi

Top 81%
×2stories
+22ft-21ft

Overall

21564

Females

8885

F18-39

8885

Passing Analysis

Category:
Athletes Passed
1334
Passed By
1687
Net Change
-353
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#20341
5K → 10K85669-584#20341#20925
10K → 15K139210-71#20925#20996
15K → 20K26671+195#20996#20801
20K → Half2829-1#20801#20802
Half → 25K21323+190#20802#20612
25K → 30K19289+103#20612#20509
30K → 20M23255-232#20509#20741
20M → 21M16112+149#20741#20592
21M → 35K3949-10#20592#20602
35K → 23M6960+9#20602#20593
23M → 24M21114-93#20593#20686
24M → 40K4534+11#20686#20675
40K → 25.2M2214+8#20675#20667
25.2M → Finish3158-27#20667#20694
TOTALS13341687-353
📊

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