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BOSTON MARATHON 2023

Shirling Tsai

Bib: 19877•F

TX

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 (F45-49)
#0 / 1817
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
8:23/mi
26:03
↑ 97↓ 3451.5%
10K· 6.21 mi
8:08/mi
51:20
↑ 79↓ 1380.4%
15K· 9.32 mi
8:33/mi
1:17:53
↑ 67↓ 78
20K· 12.43 mi
8:20/mi
1:43:46
↑ 106↓ 860.1%
Half· 13.11 mi
8:15/mi
1:49:24
↑ 19↓ 370.5%
25K· 15.53 mi
8:31/mi
2:10:04
↑ 66↓ 880.2%
30K· 18.64 mi
8:55/mi
2:37:45
↑ 181↓ 1480.2%
20M
8:59/mi
2:49:58
↑ 64↓ 500.2%
21M
9:13/mi
2:59:11
↑ 106↓ 241.6%
35K· 21.75 mi
8:57/mi
3:05:53
↑ 17↓ 861.7%
23M
9:21/mi
3:17:36
↑ 23↓ 630.6%
24M
10:18/mi
3:27:54
↓ 821.3%
40K· 24.85 mi
9:07/mi
3:35:42
↓ 200.3%
25.2M
9:52/mi
3:39:06
↑ 13↓ 160.2%
Finish· 26.22 mi
8:53/mi
3:48:09
↑ 22↓ 21

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:49:24
Pace8:21 /mi
2nd Half
Distance13.11 mi
Time1:58:45
Pace9:04 /mi
📊Positive Split: 8.5% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi11:17:3926:038:2326:03
8:23
-
10K
6.21 mi11:42:5651:208:1625:17
8:08
-0:15
15K
9.32 mi12:09:291:17:538:2126:33
8:33
+0:25
20K
12.43 mi12:35:221:43:468:2125:53
8:20
-0:13
Half
13.11 mi12:41:001:49:248:215:38
8:15
-0:05
25K
15.53 mi13:01:402:10:048:2220:40
8:31
+0:16
30K
18.64 mi13:29:212:37:458:2827:41
8:55
+0:24
20M
20.00 mi13:41:342:49:588:3012:13
8:59
+0:04
21M
21.00 mi13:50:472:59:118:329:13
9:13
+0:14
35K
21.75 mi13:57:293:05:538:336:42
8:57
-0:16
23M
23.00 mi14:09:123:17:368:3511:43
9:21
+0:24
24M
24.00 mi14:19:303:27:548:4010:18
10:18
+0:57
40K
24.85 mi14:27:183:35:428:417:48
9:07
-1:11
25.2M
25.20 mi14:30:423:39:068:423:24
9:52
+0:45
Finish
26.22 mi14:39:453:48:098:429:03
8:53
-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

8:08 /mi

Average Pace

8:42 /mi

Slowest Pace

10:18 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

2:10:04

57% of race

Time at Steady Pace

1:03:27

28% of race

Time at Slower Pace

34:38

15% 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 mi11:17:3926:038:2326:03
8:23
#16776
10K
6.21 mi11:42:5651:208:1625:17
8:08
#16253
15K
9.32 mi12:09:291:17:538:2126:33
8:33
#16898
20K
12.43 mi12:35:221:43:468:2125:53
8:20
#16632
Half
13.11 mi12:41:001:49:248:215:38
8:15
#16604
25K
15.53 mi13:01:402:10:048:2220:40
8:31
#16561
30K
18.64 mi13:29:212:37:458:2827:41
8:55
#16544
20M
20.00 mi13:41:342:49:588:3012:13
8:59
#16527
21M
21.00 mi13:50:472:59:118:329:13
9:13
#16386
35K
21.75 mi13:57:293:05:538:336:42
8:57
#16438
23M
23.00 mi14:09:123:17:368:3511:43
9:21
#16533
24M
24.00 mi14:19:303:27:548:4010:18
10:18
#16891
40K
24.85 mi14:27:183:35:428:417:48
9:07
#16862
25.2M
25.20 mi14:30:423:39:068:423:24
9:52
#16877
Finish
26.22 mi14:39:453:48:098:429:03
8:53
#16898
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallFemalesF45-49Seg. OverallSeg. FemalesSeg. F45-49
5K3.11 mi3.11 mi167765782578218122(Top 68%)6570(Top 58%)6570(Top 362%)
10K6.21 mi3.10 mi16253+5235429+3535429+35315816(Top 59%)5158(Top 45%)5158(Top 284%)
15K9.32 mi3.11 mi16898-6455853-4245853-42418122(Top 68%)6570(Top 58%)6570(Top 362%)
20K12.43 mi3.11 mi16632+2665697+1565697+15615822(Top 59%)5244(Top 46%)5244(Top 289%)
Half13.11 mi0.68 mi16604+285685+125685+1216274(Top 61%)5475(Top 48%)5475(Top 301%)
25K15.53 mi2.42 mi16561+435673+125673+1216366(Top 61%)5654(Top 49%)5654(Top 311%)
30K18.64 mi3.11 mi16544+175707-345707-3416715(Top 63%)5900(Top 52%)5900(Top 325%)
20M20.00 mi1.36 mi16527+175717-105717-1016505(Top 62%)5870(Top 51%)5870(Top 323%)
21M21.00 mi1.00 mi16386+1415646+715646+7114603(Top 55%)4833(Top 42%)4833(Top 266%)
35K21.75 mi0.75 mi16438-525681-355681-3517734(Top 67%)6682(Top 58%)6682(Top 368%)
23M23.00 mi1.25 mi16533-955747-665747-6617764(Top 67%)6725(Top 59%)6725(Top 370%)
24M24.00 mi1.00 mi16891-3585975-2285975-22821566(Top 81%)8876(Top 78%)8876(Top 488%)
40K24.85 mi0.85 mi16862+295982-75982-716747(Top 63%)6259(Top 55%)6259(Top 344%)
25.2M25.20 mi0.35 mi16877-155998-165998-1616850(Top 63%)6341(Top 56%)6341(Top 349%)
Finish26.22 mi1.02 mi16898-216020-226020-2217432(Top 65%)6606(Top 58%)6606(Top 364%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 68%
×21story building
+97ft-345ft

Overall

18122

Females

6570

F45-49

6570

5K→10K

3.1 - 6.2 mi

Top 59%
×5story building
+79ft-138ft

Overall

15816

Females

5158

F45-49

5158

10K→15K

6.2 - 9.3 mi

Top 68%
×3story building
+67ft-78ft

Overall

18122

Females

6570

F45-49

6570

15K→20K

9.3 - 12.4 mi

Top 59%
×5story building
+106ft-86ft

Overall

15822

Females

5244

F45-49

5244

20K→Half

12.4 - 13.1 mi

Top 61%
×2story building
+19ft-37ft

Overall

16274

Females

5475

F45-49

5475

Half→25K

13.1 - 15.5 mi

Top 61%
×4story building
+66ft-88ft

Overall

16366

Females

5654

F45-49

5654

25K→30K

15.5 - 18.6 mi

Top 63%
×9story building
+181ft-148ft

Overall

16715

Females

5900

F45-49

5900

30K→20M

18.6 - 20.0 mi

Top 62%
×5story building
+64ft-50ft

Overall

16505

Females

5870

F45-49

5870

20M→21M

20.0 - 21.0 mi

Top 55%
×8story building
+106ft-24ft

Overall

14603

Females

4833

F45-49

4833

21M→35K

21.0 - 21.8 mi

Top 67%
×7story building
+17ft-86ft

Overall

17734

Females

6682

F45-49

6682

35K→23M

21.8 - 23.0 mi

Top 67%
×5story building
+23ft-63ft

Overall

17764

Females

6725

F45-49

6725

23M→24M

23.0 - 24.0 mi

Top 81%
×6story building
+12ft-82ft

Overall

21566

Females

8876

F45-49

8876

24M→40K

24.0 - 24.9 mi

Top 63%
×1story
+6ft-20ft

Overall

16747

Females

6259

F45-49

6259

40K→25.2M

24.9 - 25.2 mi

Top 63%
×1story
+13ft-16ft

Overall

16850

Females

6341

F45-49

6341

25.2M→Finish

25.2 - 26.2 mi

Top 65%
×2story building
+22ft-21ft

Overall

17432

Females

6606

F45-49

6606

Passing Analysis

Category:
Athletes Passed
1907
Passed By
2029
Net Change
-122
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#16776
5K → 10K646123+523#16776#16253
10K → 15K47692-645#16253#16898
15K → 20K32357+266#16898#16632
20K → Half4214+28#16632#16604
Half → 25K154111+43#16604#16561
25K → 30K191174+17#16561#16544
30K → 20M9679+17#16544#16527
20M → 21M16019+141#16527#16386
21M → 35K2880-52#16386#16438
35K → 23M59154-95#16438#16533
23M → 24M10368-358#16533#16891
24M → 40K6839+29#16891#16862
40K → 25.2M2439-15#16862#16877
25.2M → Finish5980-21#16877#16898
TOTALS19072029-122
📊

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