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BOSTON MARATHON 2023

Chelsey Giffin

Bib: 12741•F

BC

0:00
0:00
/ mi
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Overall
#0 / 26622
Top 23%
Gender (Female)
#0 / 11423
Top 6%
Division (F18-39)
#0 / 4884
Top 11%
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
7:15/mi
22:32
↑ 97↓ 3451.5%
10K· 6.21 mi
7:12/mi
44:55
↑ 79↓ 1380.4%
15K· 9.32 mi
7:05/mi
1:06:56
↑ 67↓ 78
20K· 12.43 mi
7:06/mi
1:28:59
↑ 106↓ 860.1%
Half· 13.11 mi
6:58/mi
1:33:44
↑ 19↓ 370.5%
25K· 15.53 mi
7:03/mi
1:50:49
↑ 66↓ 880.2%
30K· 18.64 mi
7:11/mi
2:13:08
↑ 181↓ 1480.2%
20M
7:09/mi
2:22:51
↑ 64↓ 500.2%
21M
7:38/mi
2:30:29
↑ 106↓ 241.6%
35K· 21.75 mi
7:04/mi
2:35:46
↑ 17↓ 861.7%
23M
7:21/mi
2:44:58
↑ 23↓ 630.6%
24M
7:14/mi
2:52:12
↓ 821.3%
40K· 24.85 mi
7:29/mi
2:58:36
↓ 200.3%
25.2M
7:53/mi
3:01:19
↑ 13↓ 160.2%
Finish· 26.22 mi
7:12/mi
3:08:39
↑ 22↓ 21

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:33:44
Pace7:09 /mi
2nd Half
Distance13.11 mi
Time1:34:55
Pace7:14 /mi
📊Positive Split: 1.3% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:50:2322:327:1522:32
7:15
-
10K
6.21 mi11:12:4644:557:1422:23
7:12
-0:03
15K
9.32 mi11:34:471:06:567:1122:01
7:05
-0:07
20K
12.43 mi11:56:501:28:597:1022:03
7:06
+0:01
Half
13.11 mi12:01:351:33:447:094:45
6:58
-0:08
25K
15.53 mi12:18:401:50:497:0817:05
7:03
+0:05
30K
18.64 mi12:40:592:13:087:0922:19
7:11
+0:08
20M
20.00 mi12:50:422:22:517:099:43
7:09
-0:02
21M
21.00 mi12:58:202:30:297:107:38
7:38
+0:29
35K
21.75 mi13:03:372:35:467:105:17
7:04
-0:34
23M
23.00 mi13:12:492:44:587:109:12
7:21
+0:17
24M
24.00 mi13:20:032:52:127:117:14
7:14
-0:07
40K
24.85 mi13:26:272:58:367:116:24
7:29
+0:15
25.2M
25.20 mi13:29:103:01:197:122:43
7:53
+0:24
Finish
26.22 mi13:36:303:08:397:127:20
7:12
-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

6:58 /mi

Average Pace

7:12 /mi

Slowest Pace

7:53 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

3:05:56

99% of race

Time at Steady Pace

2:43

1% of race

Time at Slower Pace

0:00

0% of race

Average Pace: 7:12 /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 mi10:50:2322:327:1522:32
7:15
#7818
10K
6.21 mi11:12:4644:557:1422:23
7:12
#7953
15K
9.32 mi11:34:471:06:567:1122:01
7:05
#7624
20K
12.43 mi11:56:501:28:597:1022:03
7:06
#7278
Half
13.11 mi12:01:351:33:447:094:45
6:58
#7237
25K
15.53 mi12:18:401:50:497:0817:05
7:03
#6969
30K
18.64 mi12:40:592:13:087:0922:19
7:11
#6632
20M
20.00 mi12:50:422:22:517:099:43
7:09
#6477
21M
21.00 mi12:58:202:30:297:107:38
7:38
#6366
35K
21.75 mi13:03:372:35:467:105:17
7:04
#6320
23M
23.00 mi13:12:492:44:587:109:12
7:21
#6226
24M
24.00 mi13:20:032:52:127:117:14
7:14
#6161
40K
24.85 mi13:26:272:58:367:116:24
7:29
#6147
25.2M
25.20 mi13:29:103:01:197:122:43
7:53
#6125
Finish
26.22 mi13:36:303:08:397:127:20
7:12
#6101
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallFemalesF18-39Seg. OverallSeg. FemalesSeg. F18-39
5K3.11 mi3.11 mi78189559557083(Top 27%)769(Top 7%)769(Top 16%)
10K6.21 mi3.10 mi7953-1351001-461001-468127(Top 31%)1083(Top 9%)1083(Top 22%)
15K9.32 mi3.11 mi7624+329905+96905+967083(Top 27%)769(Top 7%)769(Top 16%)
20K12.43 mi3.11 mi7278+346819+86819+866550(Top 25%)668(Top 6%)668(Top 14%)
Half13.11 mi0.68 mi7237+41808+11808+116394(Top 24%)606(Top 5%)606(Top 12%)
25K15.53 mi2.42 mi6969+268747+61747+615838(Top 22%)513(Top 4%)513(Top 11%)
30K18.64 mi3.11 mi6632+337685+62685+625416(Top 20%)485(Top 4%)485(Top 10%)
20M20.00 mi1.36 mi6477+155659+26659+264893(Top 18%)438(Top 4%)438(Top 9%)
21M21.00 mi1.00 mi6366+111638+21638+215302(Top 20%)611(Top 5%)611(Top 13%)
35K21.75 mi0.75 mi6320+46634+4634+45727(Top 22%)673(Top 6%)673(Top 14%)
23M23.00 mi1.25 mi6226+94623+11623+115580(Top 21%)679(Top 6%)679(Top 14%)
24M24.00 mi1.00 mi6161+65625-2625-25968(Top 22%)876(Top 8%)876(Top 18%)
40K24.85 mi0.85 mi6147+14632-7632-76648(Top 25%)1214(Top 11%)1214(Top 25%)
25.2M25.20 mi0.35 mi6125+22630+2630+25860(Top 22%)991(Top 9%)991(Top 20%)
Finish26.22 mi1.02 mi6101+24640-10640-106416(Top 24%)1194(Top 10%)1194(Top 24%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 27%
×21story building
+97ft-345ft

Overall

7083

Females

769

F18-39

769

5K→10K

3.1 - 6.2 mi

Top 31%
×5story building
+79ft-138ft

Overall

8127

Females

1083

F18-39

1083

10K→15K

6.2 - 9.3 mi

Top 27%
×3story building
+67ft-78ft

Overall

7083

Females

769

F18-39

769

15K→20K

9.3 - 12.4 mi

Top 25%
×5story building
+106ft-86ft

Overall

6550

Females

668

F18-39

668

20K→Half

12.4 - 13.1 mi

Top 24%
×2story building
+19ft-37ft

Overall

6394

Females

606

F18-39

606

Half→25K

13.1 - 15.5 mi

Top 22%
×4story building
+66ft-88ft

Overall

5838

Females

513

F18-39

513

25K→30K

15.5 - 18.6 mi

Top 20%
×9story building
+181ft-148ft

Overall

5416

Females

485

F18-39

485

30K→20M

18.6 - 20.0 mi

Top 18%
×5story building
+64ft-50ft

Overall

4893

Females

438

F18-39

438

20M→21M

20.0 - 21.0 mi

Top 20%
×8story building
+106ft-24ft

Overall

5302

Females

611

F18-39

611

21M→35K

21.0 - 21.8 mi

Top 22%
×7story building
+17ft-86ft

Overall

5727

Females

673

F18-39

673

35K→23M

21.8 - 23.0 mi

Top 21%
×5story building
+23ft-63ft

Overall

5580

Females

679

F18-39

679

23M→24M

23.0 - 24.0 mi

Top 22%
×6story building
+12ft-82ft

Overall

5968

Females

876

F18-39

876

24M→40K

24.0 - 24.9 mi

Top 25%
×1story
+6ft-20ft

Overall

6648

Females

1214

F18-39

1214

40K→25.2M

24.9 - 25.2 mi

Top 22%
×1story
+13ft-16ft

Overall

5860

Females

991

F18-39

991

25.2M→Finish

25.2 - 26.2 mi

Top 24%
×2story building
+22ft-21ft

Overall

6416

Females

1194

F18-39

1194

Passing Analysis

Category:
Athletes Passed
2218
Passed By
501
Net Change
+1717
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#7818
5K → 10K163298-135#7818#7953
10K → 15K35324+329#7953#7624
15K → 20K3548+346#7624#7278
20K → Half454+41#7278#7237
Half → 25K2713+268#7237#6969
25K → 30K3425+337#6969#6632
30K → 20M1605+155#6632#6477
20M → 21M1198+111#6477#6366
21M → 35K5812+46#6366#6320
35K → 23M11723+94#6320#6226
23M → 24M9025+65#6226#6161
24M → 40K5238+14#6161#6147
40K → 25.2M3513+22#6147#6125
25.2M → Finish5935+24#6125#6101
TOTALS2218501+1717
📊

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