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BOSTON MARATHON 2025

Kuangyi Tsai

Bib: 30280•M

CA

0:00
0:00
/ mi
Masters
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Overall
#0 / 28404
Gender (Male)
#0 / 16105
Masters (Masters Men)
#0 / 10463
Division (M45-49)
#0 / 2386
Race Day Weather
50°/40°F
broken clouds

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
28:20
Rank: #22910
Start → 5K
28:20 | 9:07/mi
10K· 6.21 mi
55:48
Rank: #22345 (+565)
5K → 10K
27:28 | 8:50/mi
15K· 9.32 mi
1:22:34
Rank: #21572 (+773)
10K → 15K
26:46 | 8:37/mi
20K· 12.43 mi
1:50:03
Rank: #21199 (+373)
15K → 20K
27:29 | 8:51/mi
Half· 13.11 mi
1:55:51
Rank: #21122 (+77)
20K → Half
5:48 | 8:30/mi
25K· 15.53 mi
2:17:16
Rank: #20791 (+331)
Half → 25K
21:25 | 8:50/mi
30K· 18.64 mi
2:46:17
Rank: #20479 (+312)
25K → 30K
29:01 | 9:20/mi
20M
2:58:54
Rank: #20302 (+177)
30K → 20M
12:37 | 9:17/mi
21M
3:09:05
Rank: #20223 (+79)
20M → 21M
10:11 | 10:11/mi
35K· 21.75 mi
3:15:41
Rank: #20107 (+116)
21M → 35K
6:36 | 8:49/mi
23M
3:27:21
Rank: #19992 (+115)
35K → 23M
11:40 | 9:19/mi
24M
3:36:02
Rank: #19804 (+188)
23M → 24M
8:41 | 8:41/mi
40K· 24.85 mi
3:43:34
Rank: #19657 (+147)
24M → 40K
7:32 | 8:49/mi
25.2M
3:47:00
Rank: #19603 (+54)
40K → 25.2M
3:26 | 9:57/mi
Finish· 26.22 mi
3:55:31
Rank: #19448 (+155)
25.2M → Finish
8:31 | 8:21/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:55:51
Pace8:50 /mi
2nd Half
Distance13.11 mi
Time1:59:40
Pace9:08 /mi
📊Positive Split: 3.3% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi11:50:0428:209:0728:20
9:07
-
10K
6.21 mi12:17:3255:488:5927:28
8:50
-0:17
15K
9.32 mi12:44:181:22:348:5226:46
8:37
-0:13
20K
12.43 mi13:11:471:50:038:5127:29
8:51
+0:14
Half
13.11 mi13:17:351:55:518:505:48
8:30
-0:21
25K
15.53 mi13:39:002:17:168:5021:25
8:50
+0:20
30K
18.64 mi14:08:012:46:178:5529:01
9:20
+0:30
20M
20.00 mi14:20:382:58:548:5712:37
9:17
-0:03
21M
21.00 mi14:30:493:09:059:0010:11
10:11
+0:54
35K
21.75 mi14:37:253:15:419:006:36
8:49
-1:22
23M
23.00 mi14:49:053:27:219:0111:40
9:19
+0:30
24M
24.00 mi14:57:463:36:029:008:41
8:41
-0:38
40K
24.85 mi15:05:183:43:349:007:32
8:49
+0:08
25.2M
25.20 mi15:08:443:47:009:003:26
9:57
+1:08
Finish
26.22 mi15:17:153:55:318:598:31
8:21
-1:36

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

8:21 /mi

Average Pace

8:59 /mi

Slowest Pace

10:11 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

14:19

6% of race

Time at Steady Pace

2:05:57

53% of race

Time at Slower Pace

1:35:15

40% of race

Average Pace: 8:59 /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 mi11:50:0428:209:0728:20
9:07
#22910
10K
6.21 mi12:17:3255:488:5927:28
8:50
#22345
15K
9.32 mi12:44:181:22:348:5226:46
8:37
#21572
20K
12.43 mi13:11:471:50:038:5127:29
8:51
#21199
Half
13.11 mi13:17:351:55:518:505:48
8:30
#21122
25K
15.53 mi13:39:002:17:168:5021:25
8:50
#20791
30K
18.64 mi14:08:012:46:178:5529:01
9:20
#20479
20M
20.00 mi14:20:382:58:548:5712:37
9:17
#20302
21M
21.00 mi14:30:493:09:059:0010:11
10:11
#20223
35K
21.75 mi14:37:253:15:419:006:36
8:49
#20107
23M
23.00 mi14:49:053:27:219:0111:40
9:19
#19992
24M
24.00 mi14:57:463:36:029:008:41
8:41
#19804
40K
24.85 mi15:05:183:43:349:007:32
8:49
#19657
25.2M
25.20 mi15:08:443:47:009:003:26
9:57
#19603
Finish
26.22 mi15:17:153:55:318:598:31
8:21
#19448
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM45-49Seg. OverallSeg. MalesSeg. M45-49
5K3.11 mi3.11 mi22910137221372220002(Top 70%)12505(Top 78%)12505(Top 524%)
10K6.21 mi3.10 mi22345+56513477+24513477+24521588(Top 76%)13163(Top 82%)13163(Top 552%)
15K9.32 mi3.11 mi21572+77313166+31113166+31120002(Top 70%)12505(Top 78%)12505(Top 524%)
20K12.43 mi3.11 mi21199+37312999+16712999+16720175(Top 71%)12540(Top 78%)12540(Top 526%)
Half13.11 mi0.68 mi21122+7712973+2612973+2619175(Top 68%)12123(Top 75%)12123(Top 508%)
25K15.53 mi2.42 mi20791+33112809+16412809+16419095(Top 67%)12018(Top 75%)12018(Top 504%)
30K18.64 mi3.11 mi20479+31212618+19112618+19119288(Top 68%)11960(Top 74%)11960(Top 501%)
20M20.00 mi1.36 mi20302+17712520+9812520+9818211(Top 64%)11326(Top 70%)11326(Top 475%)
21M21.00 mi1.00 mi20223+7912458+6212458+6218964(Top 67%)11598(Top 72%)11598(Top 486%)
35K21.75 mi0.75 mi20107+11612402+5612402+5617356(Top 61%)10760(Top 67%)10760(Top 451%)
23M23.00 mi1.25 mi19992+11512323+7912323+7917844(Top 63%)10893(Top 68%)10893(Top 457%)
24M24.00 mi1.00 mi19804+18812212+11112212+11115632(Top 55%)9891(Top 61%)9891(Top 415%)
40K24.85 mi0.85 mi19657+14712129+8312129+8315245(Top 54%)9556(Top 59%)9556(Top 401%)
25.2M25.20 mi0.35 mi19603+5412094+3512094+3516803(Top 59%)10286(Top 64%)10286(Top 431%)
Finish26.22 mi1.02 mi19448+15512013+8112013+8115292(Top 54%)9622(Top 60%)9622(Top 403%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 70%
×21stories
+97ft-345ft

Overall

20002

Males

12505

M45-49

12505

5K→10K

3.1 - 6.2 mi

Top 76%
×5stories
+79ft-138ft

Overall

21588

Males

13163

M45-49

13163

10K→15K

6.2 - 9.3 mi

Top 70%
×3stories
+67ft-78ft

Overall

20002

Males

12505

M45-49

12505

15K→20K

9.3 - 12.4 mi

Top 71%
×5stories
+106ft-86ft

Overall

20175

Males

12540

M45-49

12540

20K→Half

12.4 - 13.1 mi

Top 68%
×2stories
+19ft-37ft

Overall

19175

Males

12123

M45-49

12123

Half→25K

13.1 - 15.5 mi

Top 67%
×4stories
+66ft-88ft

Overall

19095

Males

12018

M45-49

12018

25K→30K

15.5 - 18.6 mi

Top 68%
×9stories
+181ft-148ft

Overall

19288

Males

11960

M45-49

11960

30K→20M

18.6 - 20.0 mi

Top 64%
×5stories
+64ft-50ft

Overall

18211

Males

11326

M45-49

11326

20M→21M

20.0 - 21.0 mi

Top 67%
×8stories
+106ft-24ft

Overall

18964

Males

11598

M45-49

11598

21M→35K

21.0 - 21.8 mi

Top 61%
×7stories
+17ft-86ft

Overall

17356

Males

10760

M45-49

10760

35K→23M

21.8 - 23.0 mi

Top 63%
×5stories
+23ft-63ft

Overall

17844

Males

10893

M45-49

10893

23M→24M

23.0 - 24.0 mi

Top 55%
×6stories
+12ft-82ft

Overall

15632

Males

9891

M45-49

9891

24M→40K

24.0 - 24.9 mi

Top 54%
×1story
+6ft-20ft

Overall

15245

Males

9556

M45-49

9556

40K→25.2M

24.9 - 25.2 mi

Top 59%
×1story
+13ft-16ft

Overall

16803

Males

10286

M45-49

10286

25.2M→Finish

25.2 - 26.2 mi

Top 54%
×2stories
+22ft-21ft

Overall

15292

Males

9622

M45-49

9622

Passing Analysis

Category:
Athletes Passed
3790
Passed By
328
Net Change
+3462
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#22910
5K → 10K62863+565#22910#22345
10K → 15K7818+773#22345#21572
15K → 20K41542+373#21572#21199
20K → Half8710+77#21199#21122
Half → 25K34413+331#21122#20791
25K → 30K38169+312#20791#20479
30K → 20M19417+177#20479#20302
20M → 21M13152+79#20302#20223
21M → 35K1248+116#20223#20107
35K → 23M14227+115#20107#19992
23M → 24M1913+188#19992#19804
24M → 40K1547+147#19804#19657
40K → 25.2M595+54#19657#19603
25.2M → Finish1594+155#19603#19448
TOTALS3790328+3462
📊

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