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BOSTON MARATHON 2023

Chang Il Yu

Bib: 31734•M

0:00
0:00
/ mi
Masters
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Overall
#0 / 26622
Gender (Male)
#0 / 15176
Masters (Masters Men)
#0 / 9891
Division (M60-64)
#0 / 1110
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
10:07/mi
31:26
↑ 97↓ 3451.5%
10K· 6.21 mi
9:34/mi
1:01:08
↑ 79↓ 1380.4%
15K· 9.32 mi
9:36/mi
1:30:59
↑ 67↓ 78
20K· 12.43 mi
9:38/mi
2:00:56
↑ 106↓ 860.1%
Half· 13.11 mi
9:14/mi
2:07:14
↑ 19↓ 370.5%
25K· 15.53 mi
9:42/mi
2:30:46
↑ 66↓ 880.2%
30K· 18.64 mi
10:19/mi
3:02:50
↑ 181↓ 1480.2%
20M
9:21/mi
3:15:33
↑ 64↓ 500.2%
21M
10:21/mi
3:25:54
↑ 106↓ 241.6%
35K· 21.75 mi
9:39/mi
3:33:07
↑ 17↓ 861.7%
23M
9:45/mi
3:45:20
↑ 23↓ 630.6%
24M
9:38/mi
3:54:58
↓ 821.3%
40K· 24.85 mi
9:37/mi
4:03:11
↓ 200.3%
25.2M
10:26/mi
4:06:47
↑ 13↓ 160.2%
Finish· 26.22 mi
9:18/mi
4:16:16
↑ 22↓ 21

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time2:07:14
Pace9:42 /mi
2nd Half
Distance13.11 mi
Time2:09:02
Pace9:51 /mi
📊Positive Split: 1.4% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi11:48:4631:2610:0731:26
10:07
-
10K
6.21 mi12:18:281:01:089:5029:42
9:34
-0:33
15K
9.32 mi12:48:191:30:599:4629:51
9:36
+0:02
20K
12.43 mi13:18:162:00:569:4429:57
9:38
+0:02
Half
13.11 mi13:24:342:07:149:426:18
9:14
-0:24
25K
15.53 mi13:48:062:30:469:4223:32
9:42
+0:28
30K
18.64 mi14:20:103:02:509:4832:04
10:19
+0:37
20M
20.00 mi14:32:533:15:339:4712:43
9:21
-0:58
21M
21.00 mi14:43:143:25:549:4810:21
10:21
+1:00
35K
21.75 mi14:50:273:33:079:487:13
9:39
-0:42
23M
23.00 mi15:02:403:45:209:4812:13
9:45
+0:06
24M
24.00 mi15:12:183:54:589:479:38
9:38
-0:07
40K
24.85 mi15:20:314:03:119:478:13
9:37
-0:01
25.2M
25.20 mi15:24:074:06:479:483:36
10:26
+0:49
Finish
26.22 mi15:33:364:16:169:479:29
9:18
-1:08

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

9:14 /mi

Average Pace

9:47 /mi

Slowest Pace

10:26 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

3:30:15

82% of race

Time at Steady Pace

46:01

18% of race

Time at Slower Pace

0:00

0% of race

Average Pace: 9:46 /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 mi11:48:4631:2610:0731:26
10:07
#23724
10K
6.21 mi12:18:281:01:089:5029:42
9:34
#23246
15K
9.32 mi12:48:191:30:599:4629:51
9:36
#23040
20K
12.43 mi13:18:162:00:569:4429:57
9:38
#22749
Half
13.11 mi13:24:342:07:149:426:18
9:14
#22692
25K
15.53 mi13:48:062:30:469:4223:32
9:42
#22490
30K
18.64 mi14:20:103:02:509:4832:04
10:19
#22350
20M
20.00 mi14:32:533:15:339:4712:43
9:21
#22102
21M
21.00 mi14:43:143:25:549:4810:21
10:21
#21939
35K
21.75 mi14:50:273:33:079:487:13
9:39
#21893
23M
23.00 mi15:02:403:45:209:4812:13
9:45
#21737
24M
24.00 mi15:12:183:54:589:479:38
9:38
#21659
40K
24.85 mi15:20:314:03:119:478:13
9:37
#21551
25.2M
25.20 mi15:24:074:06:479:483:36
10:26
#21507
Finish
26.22 mi15:33:364:16:169:479:29
9:18
#21430
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM60-64Seg. OverallSeg. MalesSeg. M60-64
5K3.11 mi3.11 mi23724139411394122534(Top 85%)13425(Top 88%)13425(Top 1209%)
10K6.21 mi3.10 mi23246+47813721+22013721+22022672(Top 85%)13470(Top 89%)13470(Top 1214%)
15K9.32 mi3.11 mi23040+20613642+7913642+7922534(Top 85%)13425(Top 88%)13425(Top 1209%)
20K12.43 mi3.11 mi22749+29113514+12813514+12821966(Top 83%)13161(Top 87%)13161(Top 1186%)
Half13.11 mi0.68 mi22692+5713480+3413480+3421254(Top 80%)12847(Top 85%)12847(Top 1157%)
25K15.53 mi2.42 mi22490+20213370+11013370+11021469(Top 81%)12906(Top 85%)12906(Top 1163%)
30K18.64 mi3.11 mi22350+14013290+8013290+8021818(Top 82%)12995(Top 86%)12995(Top 1171%)
20M20.00 mi1.36 mi22102+24813176+11413176+11418266(Top 69%)11362(Top 75%)11362(Top 1024%)
21M21.00 mi1.00 mi21939+16313095+8113095+8119148(Top 72%)11698(Top 77%)11698(Top 1054%)
35K21.75 mi0.75 mi21893+4613077+1813077+1820296(Top 76%)12170(Top 80%)12170(Top 1096%)
23M23.00 mi1.25 mi21737+15612980+9712980+9719286(Top 72%)11696(Top 77%)11696(Top 1054%)
24M24.00 mi1.00 mi21659+7812934+4612934+4619686(Top 74%)11866(Top 78%)11866(Top 1069%)
40K24.85 mi0.85 mi21551+10812874+6012874+6018720(Top 70%)11367(Top 75%)11367(Top 1024%)
25.2M25.20 mi0.35 mi21507+4412853+2112853+2118895(Top 71%)11430(Top 75%)11430(Top 1030%)
Finish26.22 mi1.02 mi21430+7712806+4712806+4719389(Top 73%)11704(Top 77%)11704(Top 1054%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 85%
×21story building
+97ft-345ft

Overall

22534

Males

13425

M60-64

13425

5K→10K

3.1 - 6.2 mi

Top 85%
×5story building
+79ft-138ft

Overall

22672

Males

13470

M60-64

13470

10K→15K

6.2 - 9.3 mi

Top 85%
×3story building
+67ft-78ft

Overall

22534

Males

13425

M60-64

13425

15K→20K

9.3 - 12.4 mi

Top 83%
×5story building
+106ft-86ft

Overall

21966

Males

13161

M60-64

13161

20K→Half

12.4 - 13.1 mi

Top 80%
×2story building
+19ft-37ft

Overall

21254

Males

12847

M60-64

12847

Half→25K

13.1 - 15.5 mi

Top 81%
×4story building
+66ft-88ft

Overall

21469

Males

12906

M60-64

12906

25K→30K

15.5 - 18.6 mi

Top 82%
×9story building
+181ft-148ft

Overall

21818

Males

12995

M60-64

12995

30K→20M

18.6 - 20.0 mi

Top 69%
×5story building
+64ft-50ft

Overall

18266

Males

11362

M60-64

11362

20M→21M

20.0 - 21.0 mi

Top 72%
×8story building
+106ft-24ft

Overall

19148

Males

11698

M60-64

11698

21M→35K

21.0 - 21.8 mi

Top 76%
×7story building
+17ft-86ft

Overall

20296

Males

12170

M60-64

12170

35K→23M

21.8 - 23.0 mi

Top 72%
×5story building
+23ft-63ft

Overall

19286

Males

11696

M60-64

11696

23M→24M

23.0 - 24.0 mi

Top 74%
×6story building
+12ft-82ft

Overall

19686

Males

11866

M60-64

11866

24M→40K

24.0 - 24.9 mi

Top 70%
×1story
+6ft-20ft

Overall

18720

Males

11367

M60-64

11367

40K→25.2M

24.9 - 25.2 mi

Top 71%
×1story
+13ft-16ft

Overall

18895

Males

11430

M60-64

11430

25.2M→Finish

25.2 - 26.2 mi

Top 73%
×2story building
+22ft-21ft

Overall

19389

Males

11704

M60-64

11704

Passing Analysis

Category:
Athletes Passed
2543
Passed By
249
Net Change
+2294
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#23724
5K → 10K53557+478#23724#23246
10K → 15K26357+206#23246#23040
15K → 20K31120+291#23040#22749
20K → Half603+57#22749#22692
Half → 25K22119+202#22692#22490
25K → 30K18949+140#22490#22350
30K → 20M2491+248#22350#22102
20M → 21M1652+163#22102#21939
21M → 35K537+46#21939#21893
35K → 23M1626+156#21893#21737
23M → 24M857+78#21737#21659
24M → 40K1102+108#21659#21551
40K → 25.2M473+44#21551#21507
25.2M → Finish9316+77#21507#21430
TOTALS2543249+2294
📊

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