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BOSTON MARATHON 2023

Shelby Joslyn

Bib: 18670•F

PA

0:00
0:00
/ mi
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Overall
#0 / 26622
Top 32%
Gender (Female)
#0 / 11423
Top 13%
Division (F18-39)
#0 / 4884
Top 24%
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
7:34/mi
23:29
↑ 97↓ 3451.5%
10K· 6.21 mi
7:21/mi
46:19
↑ 79↓ 1380.4%
15K· 9.32 mi
7:25/mi
1:09:21
↑ 67↓ 78
20K· 12.43 mi
7:20/mi
1:32:07
↑ 106↓ 860.1%
Half· 13.11 mi
7:15/mi
1:37:04
↑ 19↓ 370.5%
25K· 15.53 mi
7:18/mi
1:54:46
↑ 66↓ 880.2%
30K· 18.64 mi
7:29/mi
2:18:00
↑ 181↓ 1480.2%
20M
7:42/mi
2:28:28
↑ 64↓ 500.2%
21M
8:11/mi
2:36:39
↑ 106↓ 241.6%
35K· 21.75 mi
7:41/mi
2:42:24
↑ 17↓ 861.7%
23M
8:02/mi
2:52:28
↑ 23↓ 630.6%
24M
8:03/mi
3:00:31
↓ 821.3%
40K· 24.85 mi
8:04/mi
3:07:25
↓ 200.3%
25.2M
8:42/mi
3:10:25
↑ 13↓ 160.2%
Finish· 26.22 mi
7:22/mi
3:17:55
↑ 22↓ 21

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:37:04
Pace7:24 /mi
2nd Half
Distance13.11 mi
Time1:40:51
Pace7:42 /mi
📊Positive Split: 3.9% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi11:14:3523:297:3423:29
7:34
-
10K
6.21 mi11:37:2546:197:2722:50
7:21
-0:13
15K
9.32 mi12:00:271:09:217:2623:02
7:25
+0:04
20K
12.43 mi12:23:131:32:077:2522:46
7:20
-0:05
Half
13.11 mi12:28:101:37:047:244:57
7:15
-0:05
25K
15.53 mi12:45:521:54:467:2317:42
7:18
+0:03
30K
18.64 mi13:09:062:18:007:2423:14
7:29
+0:11
20M
20.00 mi13:19:342:28:287:2510:28
7:42
+0:13
21M
21.00 mi13:27:452:36:397:288:11
8:11
+0:29
35K
21.75 mi13:33:302:42:247:285:45
7:41
-0:30
23M
23.00 mi13:43:342:52:287:3010:04
8:02
+0:21
24M
24.00 mi13:51:373:00:317:318:03
8:03
+0:01
40K
24.85 mi13:58:313:07:257:326:54
8:04
+0:01
25.2M
25.20 mi14:01:313:10:257:333:00
8:42
+0:38
Finish
26.22 mi14:09:013:17:557:337:30
7:22
-1:20

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

7:15 /mi

Average Pace

7:33 /mi

Slowest Pace

8:42 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

1:08:15

34% of race

Time at Steady Pace

1:33:28

47% of race

Time at Slower Pace

36:12

18% of race

Average Pace: 7:33 /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 mi11:14:3523:297:3423:29
7:34
#10148
10K
6.21 mi11:37:2546:197:2722:50
7:21
#9612
15K
9.32 mi12:00:271:09:217:2623:02
7:25
#9535
20K
12.43 mi12:23:131:32:077:2522:46
7:20
#9098
Half
13.11 mi12:28:101:37:047:244:57
7:15
#9054
25K
15.53 mi12:45:521:54:467:2317:42
7:18
#8741
30K
18.64 mi13:09:062:18:007:2423:14
7:29
#8383
20M
20.00 mi13:19:342:28:287:2510:28
7:42
#8342
21M
21.00 mi13:27:452:36:397:288:11
8:11
#8340
35K
21.75 mi13:33:302:42:247:285:45
7:41
#8404
23M
23.00 mi13:43:342:52:287:3010:04
8:02
#8462
24M
24.00 mi13:51:373:00:317:318:03
8:03
#8575
40K
24.85 mi13:58:313:07:257:326:54
8:04
#8628
25.2M
25.20 mi14:01:313:10:257:333:00
8:42
#8659
Finish
26.22 mi14:09:013:17:557:337:30
7:22
#8596
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallFemalesF18-39Seg. OverallSeg. FemalesSeg. F18-39
5K3.11 mi3.11 mi10148192919299463(Top 36%)1605(Top 14%)1605(Top 33%)
10K6.21 mi3.10 mi9612+5361663+2661663+2669234(Top 35%)1507(Top 13%)1507(Top 31%)
15K9.32 mi3.11 mi9535+771633+301633+309463(Top 36%)1605(Top 14%)1605(Top 33%)
20K12.43 mi3.11 mi9098+4371477+1561477+1568017(Top 30%)1112(Top 10%)1112(Top 23%)
Half13.11 mi0.68 mi9054+441466+111466+118325(Top 31%)1230(Top 11%)1230(Top 25%)
25K15.53 mi2.42 mi8741+3131352+1141352+1147309(Top 27%)947(Top 8%)947(Top 19%)
30K18.64 mi3.11 mi8383+3581258+941258+947086(Top 27%)956(Top 8%)956(Top 20%)
20M20.00 mi1.36 mi8342+411271-131271-138227(Top 31%)1486(Top 13%)1486(Top 30%)
21M21.00 mi1.00 mi8340+21284-131284-138545(Top 32%)1733(Top 15%)1733(Top 35%)
35K21.75 mi0.75 mi8404-641311-271311-279857(Top 37%)2282(Top 20%)2282(Top 47%)
23M23.00 mi1.25 mi8462-581357-461357-4610047(Top 38%)2524(Top 22%)2524(Top 52%)
24M24.00 mi1.00 mi8575-1131416-591416-5911586(Top 44%)3364(Top 29%)3364(Top 69%)
40K24.85 mi0.85 mi8628-531459-431459-4310518(Top 40%)2880(Top 25%)2880(Top 59%)
25.2M25.20 mi0.35 mi8659-311482-231482-2310765(Top 40%)3039(Top 27%)3039(Top 62%)
Finish26.22 mi1.02 mi8596+631479+31479+37529(Top 28%)1634(Top 14%)1634(Top 33%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 36%
×21story building
+97ft-345ft

Overall

9463

Females

1605

F18-39

1605

5K→10K

3.1 - 6.2 mi

Top 35%
×5story building
+79ft-138ft

Overall

9234

Females

1507

F18-39

1507

10K→15K

6.2 - 9.3 mi

Top 36%
×3story building
+67ft-78ft

Overall

9463

Females

1605

F18-39

1605

15K→20K

9.3 - 12.4 mi

Top 30%
×5story building
+106ft-86ft

Overall

8017

Females

1112

F18-39

1112

20K→Half

12.4 - 13.1 mi

Top 31%
×2story building
+19ft-37ft

Overall

8325

Females

1230

F18-39

1230

Half→25K

13.1 - 15.5 mi

Top 27%
×4story building
+66ft-88ft

Overall

7309

Females

947

F18-39

947

25K→30K

15.5 - 18.6 mi

Top 27%
×9story building
+181ft-148ft

Overall

7086

Females

956

F18-39

956

30K→20M

18.6 - 20.0 mi

Top 31%
×5story building
+64ft-50ft

Overall

8227

Females

1486

F18-39

1486

20M→21M

20.0 - 21.0 mi

Top 32%
×8story building
+106ft-24ft

Overall

8545

Females

1733

F18-39

1733

21M→35K

21.0 - 21.8 mi

Top 37%
×7story building
+17ft-86ft

Overall

9857

Females

2282

F18-39

2282

35K→23M

21.8 - 23.0 mi

Top 38%
×5story building
+23ft-63ft

Overall

10047

Females

2524

F18-39

2524

23M→24M

23.0 - 24.0 mi

Top 44%
×6story building
+12ft-82ft

Overall

11586

Females

3364

F18-39

3364

24M→40K

24.0 - 24.9 mi

Top 40%
×1story
+6ft-20ft

Overall

10518

Females

2880

F18-39

2880

40K→25.2M

24.9 - 25.2 mi

Top 40%
×1story
+13ft-16ft

Overall

10765

Females

3039

F18-39

3039

25.2M→Finish

25.2 - 26.2 mi

Top 28%
×2story building
+22ft-21ft

Overall

7529

Females

1634

F18-39

1634

Passing Analysis

Category:
Athletes Passed
2496*
Passed By
944
Net Change
+1552
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#10148
5K → 10K647*111+536#10148#9612
10K → 15K201124+77#9612#9535
15K → 20K44710+437#9535#9098
20K → Half5410+44#9098#9054
Half → 25K3185+313#9054#8741
25K → 30K38325+358#8741#8383
30K → 20M9049+41#8383#8342
20M → 21M7068+2#8342#8340
21M → 35K3195-64#8340#8404
35K → 23M63121-58#8404#8462
23M → 24M42155-113#8462#8575
24M → 40K4396-53#8575#8628
40K → 25.2M1445-31#8628#8659
25.2M → Finish9330+63#8659#8596
TOTALS2496*944+1552

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

📊

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