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BOSTON MARATHON 2023

Chelsea Mossey

Bib: 14094•F

BC

0:00
0:00
/ mi
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Overall
#0 / 26622
Top 39%
Gender (Female)
#0 / 11423
Top 20%
Division (F18-39)
#0 / 4884
Top 36%
Race Day Weather
49°/39°F
light intensity drizzle

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
23:46
Rank: #11030
Start → 5K
23:46 | 7:39/mi
10K· 6.21 mi
47:14
Rank: #10939 (+91)
5K → 10K
23:28 | 7:33/mi
15K· 9.32 mi
1:10:28
Rank: #10593 (+346)
10K → 15K
23:14 | 7:29/mi
20K· 12.43 mi
1:34:20
Rank: #10630 (-37)
15K → 20K
23:52 | 7:41/mi
Half· 13.11 mi
1:39:32
Rank: #10669 (-39)
20K → Half
5:12 | 7:37/mi
25K· 15.53 mi
1:59:08
Rank: #11053 (-384)
Half → 25K
19:36 | 8:05/mi
30K· 18.64 mi
2:23:55
Rank: #10926 (+127)
25K → 30K
24:47 | 7:59/mi
20M
2:34:49
Rank: #10850 (+76)
30K → 20M
10:54 | 8:01/mi
21M
2:43:20
Rank: #10826 (+24)
20M → 21M
8:31 | 8:31/mi
35K· 21.75 mi
2:49:12
Rank: #10817 (+9)
21M → 35K
5:52 | 7:51/mi
23M
2:59:16
Rank: #10770 (+47)
35K → 23M
10:04 | 8:02/mi
24M
3:07:03
Rank: #10697 (+73)
23M → 24M
7:47 | 7:47/mi
40K· 24.85 mi
3:13:45
Rank: #10590 (+107)
24M → 40K
6:42 | 7:50/mi
25.2M
3:16:36
Rank: #10531 (+59)
40K → 25.2M
2:51 | 8:16/mi
Finish· 26.22 mi
3:24:23
Rank: #10474 (+57)
25.2M → Finish
7:47 | 7:38/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:39:32
Pace7:36 /mi
2nd Half
Distance13.11 mi
Time1:44:51
Pace8:00 /mi
📊Positive Split: 5.3% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:53:2523:467:3923:46
7:39
-
10K
6.21 mi11:16:5347:147:3623:28
7:33
-0:06
15K
9.32 mi11:40:071:10:287:3423:14
7:29
-0:04
20K
12.43 mi12:03:591:34:207:3523:52
7:41
+0:12
Half
13.11 mi12:09:111:39:327:365:12
7:37
-0:04
25K
15.53 mi12:28:471:59:087:4019:36
8:05
+0:28
30K
18.64 mi12:53:342:23:557:4324:47
7:59
-0:06
20M
20.00 mi13:04:282:34:497:4410:54
8:01
+0:02
21M
21.00 mi13:12:592:43:207:478:31
8:31
+0:30
35K
21.75 mi13:18:512:49:127:475:52
7:51
-0:40
23M
23.00 mi13:28:552:59:167:4810:04
8:02
+0:11
24M
24.00 mi13:36:423:07:037:487:47
7:47
-0:15
40K
24.85 mi13:43:243:13:457:486:42
7:50
+0:03
25.2M
25.20 mi13:46:153:16:367:482:51
8:16
+0:26
Finish
26.22 mi13:54:023:24:237:487:47
7:38
-0:38

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

7:29 /mi

Average Pace

7:48 /mi

Slowest Pace

8:31 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

3:13:01

94% of race

Time at Steady Pace

11:22

6% of race

Time at Slower Pace

0:00

0% of race

Average Pace: 7:48 /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 mi10:53:2523:467:3923:46
7:39
#11030
10K
6.21 mi11:16:5347:147:3623:28
7:33
#10939
15K
9.32 mi11:40:071:10:287:3423:14
7:29
#10593
20K
12.43 mi12:03:591:34:207:3523:52
7:41
#10630
Half
13.11 mi12:09:111:39:327:365:12
7:37
#10669
25K
15.53 mi12:28:471:59:087:4019:36
8:05
#11053
30K
18.64 mi12:53:342:23:557:4324:47
7:59
#10926
20M
20.00 mi13:04:282:34:497:4410:54
8:01
#10850
21M
21.00 mi13:12:592:43:207:478:31
8:31
#10826
35K
21.75 mi13:18:512:49:127:475:52
7:51
#10817
23M
23.00 mi13:28:552:59:167:4810:04
8:02
#10770
24M
24.00 mi13:36:423:07:037:487:47
7:47
#10697
40K
24.85 mi13:43:243:13:457:486:42
7:50
#10590
25.2M
25.20 mi13:46:153:16:367:482:51
8:16
#10531
Finish
26.22 mi13:54:023:24:237:487:47
7:38
#10474
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallFemalesF18-39Seg. OverallSeg. FemalesSeg. F18-39
5K3.11 mi3.11 mi110302343234310017(Top 38%)1852(Top 16%)1852(Top 38%)
10K6.21 mi3.10 mi10939+912296+472296+4710918(Top 41%)2270(Top 20%)2270(Top 46%)
15K9.32 mi3.11 mi10593+3462119+1772119+17710017(Top 38%)1852(Top 16%)1852(Top 38%)
20K12.43 mi3.11 mi10630-372145-262145-2610786(Top 41%)2304(Top 20%)2304(Top 47%)
Half13.11 mi0.68 mi10669-392166-212166-2111256(Top 42%)2487(Top 22%)2487(Top 51%)
25K15.53 mi2.42 mi11053-3842382-2162382-21613401(Top 50%)3856(Top 34%)3856(Top 79%)
30K18.64 mi3.11 mi10926+1272359+232359+2310711(Top 40%)2496(Top 22%)2496(Top 51%)
20M20.00 mi1.36 mi10850+762358+12358+110445(Top 39%)2453(Top 21%)2453(Top 50%)
21M21.00 mi1.00 mi10826+242371-132371-1310589(Top 40%)2662(Top 23%)2662(Top 55%)
35K21.75 mi0.75 mi10817+92383-122383-1210978(Top 41%)2855(Top 25%)2855(Top 58%)
23M23.00 mi1.25 mi10770+472391-82391-810059(Top 38%)2536(Top 22%)2536(Top 52%)
24M24.00 mi1.00 mi10697+732376+152376+159682(Top 36%)2431(Top 21%)2431(Top 50%)
40K24.85 mi0.85 mi10590+1072362+142362+148935(Top 34%)2151(Top 19%)2151(Top 44%)
25.2M25.20 mi0.35 mi10531+592334+282334+288180(Top 31%)1907(Top 17%)1907(Top 39%)
Finish26.22 mi1.02 mi10474+57233423349571(Top 36%)2501(Top 22%)2501(Top 51%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 38%
×21stories
+97ft-345ft

Overall

10017

Females

1852

F18-39

1852

5K→10K

3.1 - 6.2 mi

Top 41%
×5stories
+79ft-138ft

Overall

10918

Females

2270

F18-39

2270

10K→15K

6.2 - 9.3 mi

Top 38%
×3stories
+67ft-78ft

Overall

10017

Females

1852

F18-39

1852

15K→20K

9.3 - 12.4 mi

Top 41%
×5stories
+106ft-86ft

Overall

10786

Females

2304

F18-39

2304

20K→Half

12.4 - 13.1 mi

Top 42%
×2stories
+19ft-37ft

Overall

11256

Females

2487

F18-39

2487

Half→25K

13.1 - 15.5 mi

Top 50%
×4stories
+66ft-88ft

Overall

13401

Females

3856

F18-39

3856

25K→30K

15.5 - 18.6 mi

Top 40%
×9stories
+181ft-148ft

Overall

10711

Females

2496

F18-39

2496

30K→20M

18.6 - 20.0 mi

Top 39%
×5stories
+64ft-50ft

Overall

10445

Females

2453

F18-39

2453

20M→21M

20.0 - 21.0 mi

Top 40%
×8stories
+106ft-24ft

Overall

10589

Females

2662

F18-39

2662

21M→35K

21.0 - 21.8 mi

Top 41%
×7stories
+17ft-86ft

Overall

10978

Females

2855

F18-39

2855

35K→23M

21.8 - 23.0 mi

Top 38%
×5stories
+23ft-63ft

Overall

10059

Females

2536

F18-39

2536

23M→24M

23.0 - 24.0 mi

Top 36%
×6stories
+12ft-82ft

Overall

9682

Females

2431

F18-39

2431

24M→40K

24.0 - 24.9 mi

Top 34%
×1story
+6ft-20ft

Overall

8935

Females

2151

F18-39

2151

40K→25.2M

24.9 - 25.2 mi

Top 31%
×1story
+13ft-16ft

Overall

8180

Females

1907

F18-39

1907

25.2M→Finish

25.2 - 26.2 mi

Top 36%
×2stories
+22ft-21ft

Overall

9571

Females

2501

F18-39

2501

Passing Analysis

Category:
Athletes Passed
1957*
Passed By
1401
Net Change
+556
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#11030
5K → 10K345254+91#11030#10939
10K → 15K40458+346#10939#10593
15K → 20K145182-37#10593#10630
20K → Half1958-39#10630#10669
Half → 25K52436-384#10669#11053
25K → 30K236109+127#11053#10926
30K → 20M128*52+76#10926#10850
20M → 21M8460+24#10850#10826
21M → 35K4839+9#10826#10817
35K → 23M10659+47#10817#10770
23M → 24M10027+73#10770#10697
24M → 40K12215+107#10697#10590
40K → 25.2M656+59#10590#10531
25.2M → Finish10346+57#10531#10474
TOTALS1957*1401+556

* Includes athletes who did not complete a segment (DNF/DNQ).

📊

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