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BOSTON MARATHON 2023

Kuangyi Tsai

Bib: 27413•M

CA

0:00
0:00
/ mi
Masters
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Overall
#0 / 26622
Gender (Male)
#0 / 15176
Masters (Masters Men)
#0 / 9891
Division (M45-49)
#0 / 2252
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
8:40/mi
26:57
↑ 97↓ 3451.5%
10K· 6.21 mi
8:05/mi
52:05
↑ 79↓ 1380.4%
15K· 9.32 mi
8:14/mi
1:17:39
↑ 67↓ 78
20K· 12.43 mi
8:13/mi
1:43:10
↑ 106↓ 860.1%
Half· 13.11 mi
8:02/mi
1:48:39
↑ 19↓ 370.5%
25K· 15.53 mi
8:30/mi
2:09:16
↑ 66↓ 880.2%
30K· 18.64 mi
8:27/mi
2:35:30
↑ 181↓ 1480.2%
20M
8:26/mi
2:46:57
↑ 64↓ 500.2%
21M
8:45/mi
2:55:42
↑ 106↓ 241.6%
35K· 21.75 mi
8:04/mi
3:01:44
↑ 17↓ 861.7%
23M
8:10/mi
3:11:58
↑ 23↓ 630.6%
24M
7:53/mi
3:19:51
↓ 821.3%
40K· 24.85 mi
8:02/mi
3:26:43
↓ 200.3%
25.2M
8:33/mi
3:29:40
↑ 13↓ 160.2%
Finish· 26.22 mi
7:26/mi
3:37:15
↑ 22↓ 21

The Course

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Half Splits

1st Half· via Half⚖️ Balanced
Distance13.11 mi
Time1:48:39
Pace8:17 /mi
2nd Half⚖️ Balanced
Distance13.11 mi
Time1:48:36
Pace8:17 /mi
📊Even Split: Consistent pacing between halves

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi11:44:1726:578:4026:57
8:40
-
10K
6.21 mi12:09:2552:058:2325:08
8:05
-0:35
15K
9.32 mi12:34:591:17:398:2025:34
8:14
+0:09
20K
12.43 mi13:00:301:43:108:1825:31
8:13
-0:01
Half
13.11 mi13:05:591:48:398:175:29
8:02
-0:11
25K
15.53 mi13:26:362:09:168:1920:37
8:30
+0:28
30K
18.64 mi13:52:502:35:308:2126:14
8:27
-0:03
20M
20.00 mi14:04:172:46:578:2111:27
8:26
-0:01
21M
21.00 mi14:13:022:55:428:228:45
8:45
+0:19
35K
21.75 mi14:19:043:01:448:216:02
8:04
-0:41
23M
23.00 mi14:29:183:11:588:2110:14
8:10
+0:06
24M
24.00 mi14:37:113:19:518:207:53
7:53
-0:17
40K
24.85 mi14:44:033:26:438:196:52
8:02
+0:09
25.2M
25.20 mi14:47:003:29:408:192:57
8:33
+0:31
Finish
26.22 mi14:54:353:37:158:187:35
7:26
-1:07

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

7:26 /mi

Average Pace

8:18 /mi

Slowest Pace

8:45 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

1:09:13

32% of race

Time at Steady Pace

2:28:02

68% of race

Time at Slower Pace

0:00

0% of race

Average Pace: 8:17 /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 mi11:44:1726:578:4026:57
8:40
#18703
10K
6.21 mi12:09:2552:058:2325:08
8:05
#17076
15K
9.32 mi12:34:591:17:398:2025:34
8:14
#16726
20K
12.43 mi13:00:301:43:108:1825:31
8:13
#16288
Half
13.11 mi13:05:591:48:398:175:29
8:02
#16188
25K
15.53 mi13:26:362:09:168:1920:37
8:30
#16182
30K
18.64 mi13:52:502:35:308:2126:14
8:27
#15758
20M
20.00 mi14:04:172:46:578:2111:27
8:26
#15540
21M
21.00 mi14:13:022:55:428:228:45
8:45
#15309
35K
21.75 mi14:19:043:01:448:216:02
8:04
#15191
23M
23.00 mi14:29:183:11:588:2110:14
8:10
#14963
24M
24.00 mi14:37:113:19:518:207:53
7:53
#14754
40K
24.85 mi14:44:033:26:438:196:52
8:02
#14570
25.2M
25.20 mi14:47:003:29:408:192:57
8:33
#14494
Finish
26.22 mi14:54:353:37:158:187:35
7:26
#14250
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM45-49Seg. OverallSeg. MalesSeg. M45-49
5K3.11 mi3.11 mi18703116771167716048(Top 60%)10704(Top 71%)10704(Top 475%)
10K6.21 mi3.10 mi17076+162711087+59011087+59015428(Top 58%)10485(Top 69%)10485(Top 466%)
15K9.32 mi3.11 mi16726+35010958+12910958+12916048(Top 60%)10704(Top 71%)10704(Top 475%)
20K12.43 mi3.11 mi16288+43810789+16910789+16915035(Top 56%)10276(Top 68%)10276(Top 456%)
Half13.11 mi0.68 mi16188+10010743+4610743+4614615(Top 55%)10135(Top 67%)10135(Top 450%)
25K15.53 mi2.42 mi16182+610717+2610717+2616201(Top 61%)10616(Top 70%)10616(Top 471%)
30K18.64 mi3.11 mi15758+42410508+20910508+20913944(Top 52%)9625(Top 63%)9625(Top 427%)
20M20.00 mi1.36 mi15540+21810406+10210406+10213160(Top 49%)9205(Top 61%)9205(Top 409%)
21M21.00 mi1.00 mi15309+23110287+11910287+11911957(Top 45%)8574(Top 56%)8574(Top 381%)
35K21.75 mi0.75 mi15191+11810230+5710230+5712559(Top 47%)8810(Top 58%)8810(Top 391%)
23M23.00 mi1.25 mi14963+22810134+9610134+9610995(Top 41%)7976(Top 53%)7976(Top 354%)
24M24.00 mi1.00 mi14754+20910022+11210022+11210409(Top 39%)7618(Top 50%)7618(Top 338%)
40K24.85 mi0.85 mi14570+1849932+909932+9010255(Top 39%)7476(Top 49%)7476(Top 332%)
25.2M25.20 mi0.35 mi14494+769892+409892+409877(Top 37%)7263(Top 48%)7263(Top 323%)
Finish26.22 mi1.02 mi14250+2449775+1179775+1178088(Top 30%)6224(Top 41%)6224(Top 276%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 60%
×21story building
+97ft-345ft

Overall

16048

Males

10704

M45-49

10704

5K→10K

3.1 - 6.2 mi

Top 58%
×5story building
+79ft-138ft

Overall

15428

Males

10485

M45-49

10485

10K→15K

6.2 - 9.3 mi

Top 60%
×3story building
+67ft-78ft

Overall

16048

Males

10704

M45-49

10704

15K→20K

9.3 - 12.4 mi

Top 56%
×5story building
+106ft-86ft

Overall

15035

Males

10276

M45-49

10276

20K→Half

12.4 - 13.1 mi

Top 55%
×2story building
+19ft-37ft

Overall

14615

Males

10135

M45-49

10135

Half→25K

13.1 - 15.5 mi

Top 61%
×4story building
+66ft-88ft

Overall

16201

Males

10616

M45-49

10616

25K→30K

15.5 - 18.6 mi

Top 52%
×9story building
+181ft-148ft

Overall

13944

Males

9625

M45-49

9625

30K→20M

18.6 - 20.0 mi

Top 49%
×5story building
+64ft-50ft

Overall

13160

Males

9205

M45-49

9205

20M→21M

20.0 - 21.0 mi

Top 45%
×8story building
+106ft-24ft

Overall

11957

Males

8574

M45-49

8574

21M→35K

21.0 - 21.8 mi

Top 47%
×7story building
+17ft-86ft

Overall

12559

Males

8810

M45-49

8810

35K→23M

21.8 - 23.0 mi

Top 41%
×5story building
+23ft-63ft

Overall

10995

Males

7976

M45-49

7976

23M→24M

23.0 - 24.0 mi

Top 39%
×6story building
+12ft-82ft

Overall

10409

Males

7618

M45-49

7618

24M→40K

24.0 - 24.9 mi

Top 39%
×1story
+6ft-20ft

Overall

10255

Males

7476

M45-49

7476

40K→25.2M

24.9 - 25.2 mi

Top 37%
×1story
+13ft-16ft

Overall

9877

Males

7263

M45-49

7263

25.2M→Finish

25.2 - 26.2 mi

Top 30%
×2story building
+22ft-21ft

Overall

8088

Males

6224

M45-49

6224

Passing Analysis

Category:
Athletes Passed
4780
Passed By
327
Net Change
+4453
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#18703
5K → 10K166538+1627#18703#17076
10K → 15K43080+350#17076#16726
15K → 20K45820+438#16726#16288
20K → Half1066+100#16288#16188
Half → 25K149143+6#16188#16182
25K → 30K44420+424#16182#15758
30K → 20M2213+218#15758#15540
20M → 21M2398+231#15540#15309
21M → 35K1180+118#15309#15191
35K → 23M2302+228#15191#14963
23M → 24M2112+209#14963#14754
24M → 40K1862+184#14754#14570
40K → 25.2M782+76#14570#14494
25.2M → Finish2451+244#14494#14250
TOTALS4780327+4453
📊

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