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BOSTON MARATHON 2023

Caroline Samson-Belair

Bib: 19097•F

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0:00
/ mi
Masters
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Overall
#0 / 26622
Gender (Female)
#0 / 11423
Masters (Masters Women)
#0 / 6539
Top 46%
Division (F45-49)
#0 / 1817
Race Day Weather
49°/39°F
light intensity drizzle

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
26:47
Rank: #18354
Start → 5K
26:47 | 8:37/mi
10K· 6.21 mi
52:49
Rank: #17911 (+443)
5K → 10K
26:02 | 8:23/mi
15K· 9.32 mi
1:20:17
Rank: #18556 (-645)
10K → 15K
27:28 | 8:50/mi
20K· 12.43 mi
1:47:00
Rank: #18267 (+289)
15K → 20K
26:43 | 8:36/mi
Half· 13.11 mi
1:52:51
Rank: #18263 (+4)
20K → Half
5:51 | 8:34/mi
25K· 15.53 mi
2:14:15
Rank: #18224 (+39)
Half → 25K
21:24 | 8:50/mi
30K· 18.64 mi
2:42:16
Rank: #18007 (+217)
25K → 30K
28:01 | 9:01/mi
20M
2:54:20
Rank: #17823 (+184)
30K → 20M
12:04 | 8:53/mi
21M
3:03:50
Rank: #17708 (+115)
20M → 21M
9:30 | 9:30/mi
35K· 21.75 mi
3:10:19
Rank: #17648 (+60)
21M → 35K
6:29 | 8:40/mi
23M
3:21:34
Rank: #17533 (+115)
35K → 23M
11:15 | 8:59/mi
24M
3:30:22
Rank: #17492 (+41)
23M → 24M
8:48 | 8:48/mi
40K· 24.85 mi
3:38:01
Rank: #17435 (+57)
24M → 40K
7:39 | 8:57/mi
25.2M
3:41:14
Rank: #17384 (+51)
40K → 25.2M
3:13 | 9:20/mi
Finish· 26.22 mi
3:49:50
Rank: #17309 (+75)
25.2M → Finish
8:36 | 8:26/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:52:51
Pace8:36 /mi
2nd Half
Distance13.11 mi
Time1:56:59
Pace8:55 /mi
📊Positive Split: 3.7% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi11:18:3826:478:3726:47
8:37
-
10K
6.21 mi11:44:4052:498:3026:02
8:23
-0:14
15K
9.32 mi12:12:081:20:178:3727:28
8:50
+0:27
20K
12.43 mi12:38:511:47:008:3726:43
8:36
-0:14
Half
13.11 mi12:44:421:52:518:365:51
8:34
-0:02
25K
15.53 mi13:06:062:14:158:3921:24
8:50
+0:16
30K
18.64 mi13:34:072:42:168:4228:01
9:01
+0:11
20M
20.00 mi13:46:112:54:208:4312:04
8:53
-0:08
21M
21.00 mi13:55:413:03:508:459:30
9:30
+0:37
35K
21.75 mi14:02:103:10:198:456:29
8:40
-0:50
23M
23.00 mi14:13:253:21:348:4611:15
8:59
+0:19
24M
24.00 mi14:22:133:30:228:468:48
8:48
-0:11
40K
24.85 mi14:29:523:38:018:467:39
8:57
+0:09
25.2M
25.20 mi14:33:053:41:148:473:13
9:20
+0:23
Finish
26.22 mi14:41:413:49:508:468:36
8:26
-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

8:23 /mi

Average Pace

8:46 /mi

Slowest Pace

9:30 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

3:37:07

94% of race

Time at Steady Pace

12:43

6% of race

Time at Slower Pace

0:00

0% of race

Average Pace: 8:46 /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 mi11:18:3826:478:3726:47
8:37
#18354
10K
6.21 mi11:44:4052:498:3026:02
8:23
#17911
15K
9.32 mi12:12:081:20:178:3727:28
8:50
#18556
20K
12.43 mi12:38:511:47:008:3726:43
8:36
#18267
Half
13.11 mi12:44:421:52:518:365:51
8:34
#18263
25K
15.53 mi13:06:062:14:158:3921:24
8:50
#18224
30K
18.64 mi13:34:072:42:168:4228:01
9:01
#18007
20M
20.00 mi13:46:112:54:208:4312:04
8:53
#17823
21M
21.00 mi13:55:413:03:508:459:30
9:30
#17708
35K
21.75 mi14:02:103:10:198:456:29
8:40
#17648
23M
23.00 mi14:13:253:21:348:4611:15
8:59
#17533
24M
24.00 mi14:22:133:30:228:468:48
8:48
#17492
40K
24.85 mi14:29:523:38:018:467:39
8:57
#17435
25.2M
25.20 mi14:33:053:41:148:473:13
9:20
#17384
Finish
26.22 mi14:41:413:49:508:468:36
8:26
#17309
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallFemalesF45-49Seg. OverallSeg. FemalesSeg. F45-49
5K3.11 mi3.11 mi183546781678119735(Top 74%)7522(Top 66%)7522(Top 414%)
10K6.21 mi3.10 mi17911+4436473+3086473+30817465(Top 66%)6163(Top 54%)6163(Top 339%)
15K9.32 mi3.11 mi18556-6456850-3776850-37719735(Top 74%)7522(Top 66%)7522(Top 414%)
20K12.43 mi3.11 mi18267+2896669+1816669+18117499(Top 66%)6225(Top 54%)6225(Top 343%)
Half13.11 mi0.68 mi18263+46670-16670-118206(Top 68%)6601(Top 58%)6601(Top 363%)
25K15.53 mi2.42 mi18224+396664+66664+618099(Top 68%)6601(Top 58%)6601(Top 363%)
30K18.64 mi3.11 mi18007+2176567+976567+9717275(Top 65%)6230(Top 55%)6230(Top 343%)
20M20.00 mi1.36 mi17823+1846473+946473+9415932(Top 60%)5539(Top 48%)5539(Top 305%)
21M21.00 mi1.00 mi17708+1156416+576416+5715982(Top 60%)5626(Top 49%)5626(Top 310%)
35K21.75 mi0.75 mi17648+606393+236393+2316277(Top 61%)5862(Top 51%)5862(Top 323%)
23M23.00 mi1.25 mi17533+1156341+526341+5216022(Top 60%)5761(Top 50%)5761(Top 317%)
24M24.00 mi1.00 mi17492+416322+196322+1916226(Top 61%)5939(Top 52%)5939(Top 327%)
40K24.85 mi0.85 mi17435+576304+186304+1815902(Top 60%)5800(Top 51%)5800(Top 319%)
25.2M25.20 mi0.35 mi17384+516285+196285+1914428(Top 54%)4998(Top 44%)4998(Top 275%)
Finish26.22 mi1.02 mi17309+756250+356250+3515054(Top 57%)5289(Top 46%)5289(Top 291%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 74%
×21stories
+97ft-345ft

Overall

19735

Females

7522

F45-49

7522

5K→10K

3.1 - 6.2 mi

Top 66%
×5stories
+79ft-138ft

Overall

17465

Females

6163

F45-49

6163

10K→15K

6.2 - 9.3 mi

Top 74%
×3stories
+67ft-78ft

Overall

19735

Females

7522

F45-49

7522

15K→20K

9.3 - 12.4 mi

Top 66%
×5stories
+106ft-86ft

Overall

17499

Females

6225

F45-49

6225

20K→Half

12.4 - 13.1 mi

Top 68%
×2stories
+19ft-37ft

Overall

18206

Females

6601

F45-49

6601

Half→25K

13.1 - 15.5 mi

Top 68%
×4stories
+66ft-88ft

Overall

18099

Females

6601

F45-49

6601

25K→30K

15.5 - 18.6 mi

Top 65%
×9stories
+181ft-148ft

Overall

17275

Females

6230

F45-49

6230

30K→20M

18.6 - 20.0 mi

Top 60%
×5stories
+64ft-50ft

Overall

15932

Females

5539

F45-49

5539

20M→21M

20.0 - 21.0 mi

Top 60%
×8stories
+106ft-24ft

Overall

15982

Females

5626

F45-49

5626

21M→35K

21.0 - 21.8 mi

Top 61%
×7stories
+17ft-86ft

Overall

16277

Females

5862

F45-49

5862

35K→23M

21.8 - 23.0 mi

Top 60%
×5stories
+23ft-63ft

Overall

16022

Females

5761

F45-49

5761

23M→24M

23.0 - 24.0 mi

Top 61%
×6stories
+12ft-82ft

Overall

16226

Females

5939

F45-49

5939

24M→40K

24.0 - 24.9 mi

Top 60%
×1story
+6ft-20ft

Overall

15902

Females

5800

F45-49

5800

40K→25.2M

24.9 - 25.2 mi

Top 54%
×1story
+13ft-16ft

Overall

14428

Females

4998

F45-49

4998

25.2M→Finish

25.2 - 26.2 mi

Top 57%
×2stories
+22ft-21ft

Overall

15054

Females

5289

F45-49

5289

Passing Analysis

Category:
Athletes Passed
2348
Passed By
1303
Net Change
+1045
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#18354
5K → 10K608165+443#18354#17911
10K → 15K41686-645#17911#18556
15K → 20K33546+289#18556#18267
20K → Half2622+4#18267#18263
Half → 25K151112+39#18263#18224
25K → 30K29982+217#18224#18007
30K → 20M1939+184#18007#17823
20M → 21M14631+115#17823#17708
21M → 35K8020+60#17708#17648
35K → 23M14328+115#17648#17533
23M → 24M8241+41#17533#17492
24M → 40K8528+57#17492#17435
40K → 25.2M6110+51#17435#17384
25.2M → Finish9823+75#17384#17309
TOTALS23481303+1045
📊

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