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BOSTON MARATHON 2023

Sandra Dalton

Bib: 21979•F

MA

0:00
0:00
/ mi
Masters
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Overall
#0 / 26622
Gender (Female)
#0 / 11423
Masters (Masters Women)
#0 / 6539
Top 43%
Division (F50-54)
#0 / 1207
Top 36%
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
8:39/mi
26:52
↑ 97↓ 3451.5%
10K· 6.21 mi
8:40/mi
53:49
↑ 79↓ 1380.4%
15K· 9.32 mi
8:39/mi
1:20:40
↑ 67↓ 78
20K· 12.43 mi
8:51/mi
1:48:10
↑ 106↓ 860.1%
Half· 13.11 mi
8:17/mi
1:53:49
↑ 19↓ 370.5%
25K· 15.53 mi
8:33/mi
2:14:32
↑ 66↓ 880.2%
30K· 18.64 mi
8:50/mi
2:41:58
↑ 181↓ 1480.2%
20M
8:51/mi
2:53:59
↑ 64↓ 500.2%
21M
9:15/mi
3:03:14
↑ 106↓ 241.6%
35K· 21.75 mi
8:39/mi
3:09:42
↑ 17↓ 861.7%
23M
8:44/mi
3:20:38
↑ 23↓ 630.6%
24M
8:30/mi
3:29:08
↓ 821.3%
40K· 24.85 mi
8:44/mi
3:36:36
↓ 200.3%
25.2M
9:05/mi
3:39:44
↑ 13↓ 160.2%
Finish· 26.22 mi
8:06/mi
3:47:59
↑ 22↓ 21

The Course

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Half Splits

1st Half· via Half⚖️ Balanced
Distance13.11 mi
Time1:53:49
Pace8:41 /mi
2nd Half⚖️ Balanced
Distance13.11 mi
Time1:54:10
Pace8:43 /mi
📊Even Split: Consistent pacing between halves

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi11:19:5126:528:3926:52
8:39
-
10K
6.21 mi11:46:4853:498:4026:57
8:40
+0:01
15K
9.32 mi12:13:391:20:408:3926:51
8:39
-0:01
20K
12.43 mi12:41:091:48:108:4227:30
8:51
+0:12
Half
13.11 mi12:46:481:53:498:415:39
8:17
-0:34
25K
15.53 mi13:07:312:14:328:4020:43
8:33
+0:16
30K
18.64 mi13:34:572:41:588:4127:26
8:50
+0:17
20M
20.00 mi13:46:582:53:598:4212:01
8:51
+0:01
21M
21.00 mi13:56:133:03:148:449:15
9:15
+0:24
35K
21.75 mi14:02:413:09:428:436:28
8:39
-0:36
23M
23.00 mi14:13:373:20:388:4310:56
8:44
+0:05
24M
24.00 mi14:22:073:29:088:438:30
8:30
-0:14
40K
24.85 mi14:29:353:36:368:437:28
8:44
+0:14
25.2M
25.20 mi14:32:433:39:448:433:08
9:05
+0:21
Finish
26.22 mi14:40:583:47:598:428:15
8:06
-0:59

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

8:06 /mi

Average Pace

8:42 /mi

Slowest Pace

9:15 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

3:35:36

95% of race

Time at Steady Pace

12:23

5% of race

Time at Slower Pace

0:00

0% of race

Average Pace: 8:42 /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 mi11:19:5126:528:3926:52
8:39
#18552
10K
6.21 mi11:46:4853:498:4026:57
8:40
#18886
15K
9.32 mi12:13:391:20:408:3926:51
8:39
#18781
20K
12.43 mi12:41:091:48:108:4227:30
8:51
#18816
Half
13.11 mi12:46:481:53:498:415:39
8:17
#18706
25K
15.53 mi13:07:312:14:328:4020:43
8:33
#18337
30K
18.64 mi13:34:572:41:588:4127:26
8:50
#17904
20M
20.00 mi13:46:582:53:598:4212:01
8:51
#17720
21M
21.00 mi13:56:133:03:148:449:15
9:15
#17540
35K
21.75 mi14:02:413:09:428:436:28
8:39
#17482
23M
23.00 mi14:13:373:20:388:4310:56
8:44
#17308
24M
24.00 mi14:22:073:29:088:438:30
8:30
#17176
40K
24.85 mi14:29:353:36:368:437:28
8:44
#17085
25.2M
25.20 mi14:32:433:39:448:433:08
9:05
#17021
Finish
26.22 mi14:40:583:47:598:428:15
8:06
#16846
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallFemalesF50-54Seg. OverallSeg. FemalesSeg. F50-54
5K3.11 mi3.11 mi185526903690318695(Top 70%)6918(Top 61%)6918(Top 573%)
10K6.21 mi3.10 mi18886-3347068-1657068-16519279(Top 72%)7250(Top 63%)7250(Top 601%)
15K9.32 mi3.11 mi18781+1056993+756993+7518695(Top 70%)6918(Top 61%)6918(Top 573%)
20K12.43 mi3.11 mi18816-357010-177010-1718952(Top 71%)7059(Top 62%)7059(Top 585%)
Half13.11 mi0.68 mi18706+1106939+716939+7116432(Top 62%)5564(Top 49%)5564(Top 461%)
25K15.53 mi2.42 mi18337+3696728+2116728+21116474(Top 62%)5707(Top 50%)5707(Top 473%)
30K18.64 mi3.11 mi17904+4336507+2216507+22116257(Top 61%)5648(Top 49%)5648(Top 468%)
20M20.00 mi1.36 mi17720+1846410+976410+9715694(Top 59%)5393(Top 47%)5393(Top 447%)
21M21.00 mi1.00 mi17540+1806321+896321+8914751(Top 55%)4909(Top 43%)4909(Top 407%)
35K21.75 mi0.75 mi17482+586293+286293+2816138(Top 61%)5777(Top 51%)5777(Top 479%)
23M23.00 mi1.25 mi17308+1746199+946199+9414618(Top 55%)4971(Top 44%)4971(Top 412%)
24M24.00 mi1.00 mi17176+1326140+596140+5914516(Top 55%)4973(Top 44%)4973(Top 412%)
40K24.85 mi0.85 mi17085+916110+306110+3014754(Top 55%)5167(Top 45%)5167(Top 428%)
25.2M25.20 mi0.35 mi17021+646077+336077+3313118(Top 49%)4316(Top 38%)4316(Top 358%)
Finish26.22 mi1.02 mi16846+1755985+925985+9212800(Top 48%)4124(Top 36%)4124(Top 342%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 70%
×21story building
+97ft-345ft

Overall

18695

Females

6918

F50-54

6918

5K→10K

3.1 - 6.2 mi

Top 72%
×5story building
+79ft-138ft

Overall

19279

Females

7250

F50-54

7250

10K→15K

6.2 - 9.3 mi

Top 70%
×3story building
+67ft-78ft

Overall

18695

Females

6918

F50-54

6918

15K→20K

9.3 - 12.4 mi

Top 71%
×5story building
+106ft-86ft

Overall

18952

Females

7059

F50-54

7059

20K→Half

12.4 - 13.1 mi

Top 62%
×2story building
+19ft-37ft

Overall

16432

Females

5564

F50-54

5564

Half→25K

13.1 - 15.5 mi

Top 62%
×4story building
+66ft-88ft

Overall

16474

Females

5707

F50-54

5707

25K→30K

15.5 - 18.6 mi

Top 61%
×9story building
+181ft-148ft

Overall

16257

Females

5648

F50-54

5648

30K→20M

18.6 - 20.0 mi

Top 59%
×5story building
+64ft-50ft

Overall

15694

Females

5393

F50-54

5393

20M→21M

20.0 - 21.0 mi

Top 55%
×8story building
+106ft-24ft

Overall

14751

Females

4909

F50-54

4909

21M→35K

21.0 - 21.8 mi

Top 61%
×7story building
+17ft-86ft

Overall

16138

Females

5777

F50-54

5777

35K→23M

21.8 - 23.0 mi

Top 55%
×5story building
+23ft-63ft

Overall

14618

Females

4971

F50-54

4971

23M→24M

23.0 - 24.0 mi

Top 55%
×6story building
+12ft-82ft

Overall

14516

Females

4973

F50-54

4973

24M→40K

24.0 - 24.9 mi

Top 55%
×1story
+6ft-20ft

Overall

14754

Females

5167

F50-54

5167

40K→25.2M

24.9 - 25.2 mi

Top 49%
×1story
+13ft-16ft

Overall

13118

Females

4316

F50-54

4316

25.2M→Finish

25.2 - 26.2 mi

Top 48%
×2story building
+22ft-21ft

Overall

12800

Females

4124

F50-54

4124

Passing Analysis

Category:
Athletes Passed
2694
Passed By
988
Net Change
+1706
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#18552
5K → 10K192526-334#18552#18886
10K → 15K240135+105#18886#18781
15K → 20K153188-35#18781#18816
20K → Half1122+110#18816#18706
Half → 25K3767+369#18706#18337
25K → 30K45522+433#18337#17904
30K → 20M19915+184#17904#17720
20M → 21M19818+180#17720#17540
21M → 35K8123+58#17540#17482
35K → 23M18511+174#17482#17308
23M → 24M14614+132#17308#17176
24M → 40K10615+91#17176#17085
40K → 25.2M706+64#17085#17021
25.2M → Finish1816+175#17021#16846
TOTALS2694988+1706
📊

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