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BOSTON MARATHON 2023

Mackenzie Vlachos

Bib: 25453•F

MA

0:00
0:00
/ mi
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Overall
#0 / 26622
Gender (Female)
#0 / 11423
Top 50%
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
28:58
Rank: #21602
Start → 5K
28:58 | 9:19/mi
10K· 6.21 mi
55:41
Rank: #20471 (+1131)
5K → 10K
26:43 | 8:36/mi
15K· 9.32 mi
1:21:52
Rank: #19521 (+950)
10K → 15K
26:11 | 8:26/mi
20K· 12.43 mi
1:48:08
Rank: #18790 (+731)
15K → 20K
26:16 | 8:27/mi
Half· 13.11 mi
1:53:46
Rank: #18686 (+104)
20K → Half
5:38 | 8:15/mi
25K· 15.53 mi
2:14:15
Rank: #18222 (+464)
Half → 25K
20:29 | 8:27/mi
30K· 18.64 mi
2:40:41
Rank: #17486 (+736)
25K → 30K
26:26 | 8:30/mi
20M
2:52:15
Rank: #17215 (+271)
30K → 20M
11:34 | 8:31/mi
21M
3:01:05
Rank: #16936 (+279)
20M → 21M
8:50 | 8:50/mi
35K· 21.75 mi
3:07:21
Rank: #16849 (+87)
21M → 35K
6:16 | 8:23/mi
23M
3:18:13
Rank: #16682 (+167)
35K → 23M
10:52 | 8:41/mi
24M
3:26:53
Rank: #16620 (+62)
23M → 24M
8:40 | 8:40/mi
40K· 24.85 mi
3:34:27
Rank: #16573 (+47)
24M → 40K
7:34 | 8:51/mi
25.2M
3:37:32
Rank: #16485 (+88)
40K → 25.2M
3:05 | 8:56/mi
Finish· 26.22 mi
3:45:40
Rank: #16305 (+180)
25.2M → Finish
8:08 | 7:59/mi

The Course

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Half Splits

1st Half· via Half
Distance13.11 mi
Time1:53:46
Pace8:41 /mi
2nd Half✓ Faster
Distance13.11 mi
Time1:51:54
Pace8:32 /mi
📊Negative Split: 1.6% faster second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi11:45:5628:589:1928:58
9:19
-
10K
6.21 mi12:12:3955:418:5826:43
8:36
-0:43
15K
9.32 mi12:38:501:21:528:4726:11
8:26
-0:10
20K
12.43 mi13:05:061:48:088:4226:16
8:27
+0:01
Half
13.11 mi13:10:441:53:468:415:38
8:15
-0:12
25K
15.53 mi13:31:132:14:158:3920:29
8:27
+0:12
30K
18.64 mi13:57:392:40:418:3726:26
8:30
+0:03
20M
20.00 mi14:09:132:52:158:3711:34
8:31
+0:01
21M
21.00 mi14:18:033:01:058:378:50
8:50
+0:19
35K
21.75 mi14:24:193:07:218:376:16
8:23
-0:27
23M
23.00 mi14:35:113:18:138:3710:52
8:41
+0:18
24M
24.00 mi14:43:513:26:538:378:40
8:40
-0:01
40K
24.85 mi14:51:253:34:278:387:34
8:51
+0:11
25.2M
25.20 mi14:54:303:37:328:383:05
8:56
+0:05
Finish
26.22 mi15:02:383:45:408:378:08
7:59
-0:57

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

7:59 /mi

Average Pace

8:37 /mi

Slowest Pace

9:19 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

2:57:13

79% of race

Time at Steady Pace

48:27

21% of race

Time at Slower Pace

0:00

0% of race

Average Pace: 8:36 /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 mi11:45:5628:589:1928:58
9:19
#21602
10K
6.21 mi12:12:3955:418:5826:43
8:36
#20471
15K
9.32 mi12:38:501:21:528:4726:11
8:26
#19521
20K
12.43 mi13:05:061:48:088:4226:16
8:27
#18790
Half
13.11 mi13:10:441:53:468:415:38
8:15
#18686
25K
15.53 mi13:31:132:14:158:3920:29
8:27
#18222
30K
18.64 mi13:57:392:40:418:3726:26
8:30
#17486
20M
20.00 mi14:09:132:52:158:3711:34
8:31
#17215
21M
21.00 mi14:18:033:01:058:378:50
8:50
#16936
35K
21.75 mi14:24:193:07:218:376:16
8:23
#16849
23M
23.00 mi14:35:113:18:138:3710:52
8:41
#16682
24M
24.00 mi14:43:513:26:538:378:40
8:40
#16620
40K
24.85 mi14:51:253:34:278:387:34
8:51
#16573
25.2M
25.20 mi14:54:303:37:328:383:05
8:56
#16485
Finish
26.22 mi15:02:383:45:408:378:08
7:59
#16305
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallFemalesF18-39Seg. OverallSeg. FemalesSeg. F18-39
5K3.11 mi3.11 mi216028690869017321(Top 65%)6115(Top 54%)6115(Top 125%)
10K6.21 mi3.10 mi20471+11318012+6788012+67818839(Top 71%)6980(Top 61%)6980(Top 143%)
15K9.32 mi3.11 mi19521+9507458+5547458+55417321(Top 65%)6115(Top 54%)6115(Top 125%)
20K12.43 mi3.11 mi18790+7316992+4666992+46616580(Top 62%)5695(Top 50%)5695(Top 117%)
Half13.11 mi0.68 mi18686+1046927+656927+6516261(Top 61%)5462(Top 48%)5462(Top 112%)
25K15.53 mi2.42 mi18222+4646662+2656662+26515913(Top 60%)5388(Top 47%)5388(Top 110%)
30K18.64 mi3.11 mi17486+7366246+4166246+41614386(Top 54%)4562(Top 40%)4562(Top 93%)
20M20.00 mi1.36 mi17215+2716108+1386108+13813739(Top 52%)4272(Top 37%)4272(Top 87%)
21M21.00 mi1.00 mi16936+2795949+1595949+15912491(Top 47%)3690(Top 32%)3690(Top 76%)
35K21.75 mi0.75 mi16849+875904+455904+4514632(Top 55%)4914(Top 43%)4914(Top 101%)
23M23.00 mi1.25 mi16682+1675838+665838+6614286(Top 54%)4786(Top 42%)4786(Top 98%)
24M24.00 mi1.00 mi16620+625818+205818+2015491(Top 58%)5531(Top 48%)5531(Top 113%)
40K24.85 mi0.85 mi16573+475808+105808+1015388(Top 58%)5520(Top 48%)5520(Top 113%)
25.2M25.20 mi0.35 mi16485+885766+425766+4212291(Top 46%)3904(Top 34%)3904(Top 80%)
Finish26.22 mi1.02 mi16305+1805663+1035663+10312045(Top 45%)3743(Top 33%)3743(Top 77%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 65%
×21stories
+97ft-345ft

Overall

17321

Females

6115

F18-39

6115

5K→10K

3.1 - 6.2 mi

Top 71%
×5stories
+79ft-138ft

Overall

18839

Females

6980

F18-39

6980

10K→15K

6.2 - 9.3 mi

Top 65%
×3stories
+67ft-78ft

Overall

17321

Females

6115

F18-39

6115

15K→20K

9.3 - 12.4 mi

Top 62%
×5stories
+106ft-86ft

Overall

16580

Females

5695

F18-39

5695

20K→Half

12.4 - 13.1 mi

Top 61%
×2stories
+19ft-37ft

Overall

16261

Females

5462

F18-39

5462

Half→25K

13.1 - 15.5 mi

Top 60%
×4stories
+66ft-88ft

Overall

15913

Females

5388

F18-39

5388

25K→30K

15.5 - 18.6 mi

Top 54%
×9stories
+181ft-148ft

Overall

14386

Females

4562

F18-39

4562

30K→20M

18.6 - 20.0 mi

Top 52%
×5stories
+64ft-50ft

Overall

13739

Females

4272

F18-39

4272

20M→21M

20.0 - 21.0 mi

Top 47%
×8stories
+106ft-24ft

Overall

12491

Females

3690

F18-39

3690

21M→35K

21.0 - 21.8 mi

Top 55%
×7stories
+17ft-86ft

Overall

14632

Females

4914

F18-39

4914

35K→23M

21.8 - 23.0 mi

Top 54%
×5stories
+23ft-63ft

Overall

14286

Females

4786

F18-39

4786

23M→24M

23.0 - 24.0 mi

Top 58%
×6stories
+12ft-82ft

Overall

15491

Females

5531

F18-39

5531

24M→40K

24.0 - 24.9 mi

Top 58%
×1story
+6ft-20ft

Overall

15388

Females

5520

F18-39

5520

40K→25.2M

24.9 - 25.2 mi

Top 46%
×1story
+13ft-16ft

Overall

12291

Females

3904

F18-39

3904

25.2M→Finish

25.2 - 26.2 mi

Top 45%
×2stories
+22ft-21ft

Overall

12045

Females

3743

F18-39

3743

Passing Analysis

Category:
Athletes Passed
5457
Passed By
160
Net Change
+5297
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#21602
5K → 10K116029+1131#21602#20471
10K → 15K9555+950#20471#19521
15K → 20K7376+731#19521#18790
20K → Half1051+104#18790#18686
Half → 25K4717+464#18686#18222
25K → 30K7371+736#18222#17486
30K → 20M2743+271#17486#17215
20M → 21M2812+279#17215#16936
21M → 35K9811+87#16936#16849
35K → 23M19225+167#16849#16682
23M → 24M9230+62#16682#16620
24M → 40K7932+47#16620#16573
40K → 25.2M891+88#16573#16485
25.2M → Finish1877+180#16485#16305
TOTALS5457160+5297
📊

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