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BOSTON MARATHON 2023

Ko Ihara

Bib: 4113•M

CA

0:00
0:00
/ mi
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Overall
#0 / 26622
Top 19%
Gender (Male)
#0 / 15176
Top 31%
Division (M18-39)
#0 / 5285
Race Day Weather
49°/39°F
light intensity drizzle

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
21:52
Rank: #6474
Start → 5K
21:52 | 7:02/mi
10K· 6.21 mi
43:16
Rank: #6293 (+181)
5K → 10K
21:24 | 6:53/mi
15K· 9.32 mi
1:04:33
Rank: #6034 (+259)
10K → 15K
21:17 | 6:51/mi
20K· 12.43 mi
1:26:11
Rank: #5951 (+83)
15K → 20K
21:38 | 6:58/mi
Half· 13.11 mi
1:30:56
Rank: #5965 (-14)
20K → Half
4:45 | 6:58/mi
25K· 15.53 mi
1:47:45
Rank: #5811 (+154)
Half → 25K
16:49 | 6:56/mi
30K· 18.64 mi
2:09:42
Rank: #5569 (+242)
25K → 30K
21:57 | 7:04/mi
20M
2:19:20
Rank: #5460 (+109)
30K → 20M
9:38 | 7:05/mi
21M
2:26:39
Rank: #5305 (+155)
20M → 21M
7:19 | 7:19/mi
35K· 21.75 mi
2:31:44
Rank: #5237 (+68)
21M → 35K
5:05 | 6:48/mi
23M
2:40:34
Rank: #5117 (+120)
35K → 23M
8:50 | 7:03/mi
24M
2:47:34
Rank: #5050 (+67)
23M → 24M
7:00 | 7:00/mi
40K· 24.85 mi
2:54:06
Rank: #5074 (-24)
24M → 40K
6:32 | 7:38/mi
25.2M
2:56:47
Rank: #5063 (+11)
40K → 25.2M
2:41 | 7:47/mi
Finish· 26.22 mi
3:04:03
Rank: #5056 (+7)
25.2M → Finish
7:16 | 7:08/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:30:56
Pace6:56 /mi
2nd Half
Distance13.11 mi
Time1:33:07
Pace7:06 /mi
📊Positive Split: 2.4% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:24:0221:527:0221:52
7:02
-
10K
6.21 mi10:45:2643:166:5821:24
6:53
-0:09
15K
9.32 mi11:06:431:04:336:5621:17
6:51
-0:02
20K
12.43 mi11:28:211:26:116:5621:38
6:58
+0:07
Half
13.11 mi11:33:061:30:566:564:45
6:58
0:00
25K
15.53 mi11:49:551:47:456:5616:49
6:56
-0:02
30K
18.64 mi12:11:522:09:426:5721:57
7:04
+0:08
20M
20.00 mi12:21:302:19:206:589:38
7:05
+0:01
21M
21.00 mi12:28:492:26:396:597:19
7:19
+0:14
35K
21.75 mi12:33:542:31:446:595:05
6:48
-0:31
23M
23.00 mi12:42:442:40:346:598:50
7:03
+0:15
24M
24.00 mi12:49:442:47:346:597:00
7:00
-0:03
40K
24.85 mi12:56:162:54:067:006:32
7:38
+0:38
25.2M
25.20 mi12:58:572:56:477:012:41
7:47
+0:09
Finish
26.22 mi13:06:133:04:037:017:16
7:08
-0:39

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

6:48 /mi

Average Pace

7:01 /mi

Slowest Pace

7:47 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

2:54:50

95% of race

Time at Steady Pace

9:13

5% of race

Time at Slower Pace

0:00

0% of race

Average Pace: 7:01 /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 mi10:24:0221:527:0221:52
7:02
#6474
10K
6.21 mi10:45:2643:166:5821:24
6:53
#6293
15K
9.32 mi11:06:431:04:336:5621:17
6:51
#6034
20K
12.43 mi11:28:211:26:116:5621:38
6:58
#5951
Half
13.11 mi11:33:061:30:566:564:45
6:58
#5965
25K
15.53 mi11:49:551:47:456:5616:49
6:56
#5811
30K
18.64 mi12:11:522:09:426:5721:57
7:04
#5569
20M
20.00 mi12:21:302:19:206:589:38
7:05
#5460
21M
21.00 mi12:28:492:26:396:597:19
7:19
#5305
35K
21.75 mi12:33:542:31:446:595:05
6:48
#5237
23M
23.00 mi12:42:442:40:346:598:50
7:03
#5117
24M
24.00 mi12:49:442:47:346:597:00
7:00
#5050
40K
24.85 mi12:56:162:54:067:006:32
7:38
#5074
25.2M
25.20 mi12:58:572:56:477:012:41
7:47
#5063
Finish
26.22 mi13:06:133:04:037:017:16
7:08
#5056
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM18-39Seg. OverallSeg. MalesSeg. M18-39
5K3.11 mi3.11 mi6474586358635565(Top 21%)5119(Top 34%)5119(Top 97%)
10K6.21 mi3.10 mi6293+1815707+1565707+1566028(Top 23%)5483(Top 36%)5483(Top 104%)
15K9.32 mi3.11 mi6034+2595507+2005507+2005565(Top 21%)5119(Top 34%)5119(Top 97%)
20K12.43 mi3.11 mi5951+835434+735434+735730(Top 22%)5253(Top 35%)5253(Top 99%)
Half13.11 mi0.68 mi5965-145446-125446-126295(Top 24%)5705(Top 38%)5705(Top 108%)
25K15.53 mi2.42 mi5811+1545330+1165330+1165182(Top 19%)4780(Top 31%)4780(Top 90%)
30K18.64 mi3.11 mi5569+2425119+2115119+2114754(Top 18%)4388(Top 29%)4388(Top 83%)
20M20.00 mi1.36 mi5460+1095023+965023+964565(Top 17%)4190(Top 28%)4190(Top 79%)
21M21.00 mi1.00 mi5305+1554885+1384885+1383723(Top 14%)3454(Top 23%)3454(Top 65%)
35K21.75 mi0.75 mi5237+684819+664819+664191(Top 16%)3841(Top 25%)3841(Top 73%)
23M23.00 mi1.25 mi5117+1204706+1134706+1134074(Top 15%)3750(Top 25%)3750(Top 71%)
24M24.00 mi1.00 mi5050+674644+624644+624677(Top 18%)4191(Top 28%)4191(Top 79%)
40K24.85 mi0.85 mi5074-244668-244668-247522(Top 28%)5934(Top 39%)5934(Top 112%)
25.2M25.20 mi0.35 mi5063+114655+134655+135249(Top 20%)4429(Top 29%)4429(Top 84%)
Finish26.22 mi1.02 mi5056+74643+124643+125965(Top 22%)4904(Top 32%)4904(Top 93%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 21%
×21stories
+97ft-345ft

Overall

5565

Males

5119

M18-39

5119

5K→10K

3.1 - 6.2 mi

Top 23%
×5stories
+79ft-138ft

Overall

6028

Males

5483

M18-39

5483

10K→15K

6.2 - 9.3 mi

Top 21%
×3stories
+67ft-78ft

Overall

5565

Males

5119

M18-39

5119

15K→20K

9.3 - 12.4 mi

Top 22%
×5stories
+106ft-86ft

Overall

5730

Males

5253

M18-39

5253

20K→Half

12.4 - 13.1 mi

Top 24%
×2stories
+19ft-37ft

Overall

6295

Males

5705

M18-39

5705

Half→25K

13.1 - 15.5 mi

Top 19%
×4stories
+66ft-88ft

Overall

5182

Males

4780

M18-39

4780

25K→30K

15.5 - 18.6 mi

Top 18%
×9stories
+181ft-148ft

Overall

4754

Males

4388

M18-39

4388

30K→20M

18.6 - 20.0 mi

Top 17%
×5stories
+64ft-50ft

Overall

4565

Males

4190

M18-39

4190

20M→21M

20.0 - 21.0 mi

Top 14%
×8stories
+106ft-24ft

Overall

3723

Males

3454

M18-39

3454

21M→35K

21.0 - 21.8 mi

Top 16%
×7stories
+17ft-86ft

Overall

4191

Males

3841

M18-39

3841

35K→23M

21.8 - 23.0 mi

Top 15%
×5stories
+23ft-63ft

Overall

4074

Males

3750

M18-39

3750

23M→24M

23.0 - 24.0 mi

Top 18%
×6stories
+12ft-82ft

Overall

4677

Males

4191

M18-39

4191

24M→40K

24.0 - 24.9 mi

Top 28%
×1story
+6ft-20ft

Overall

7522

Males

5934

M18-39

5934

40K→25.2M

24.9 - 25.2 mi

Top 20%
×1story
+13ft-16ft

Overall

5249

Males

4429

M18-39

4429

25.2M→Finish

25.2 - 26.2 mi

Top 22%
×2stories
+22ft-21ft

Overall

5965

Males

4904

M18-39

4904

Passing Analysis

Category:
Athletes Passed
1858
Passed By
440
Net Change
+1418
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#6474
5K → 10K299118+181#6474#6293
10K → 15K28223+259#6293#6034
15K → 20K14461+83#6034#5951
20K → Half1428-14#5951#5965
Half → 25K17723+154#5965#5811
25K → 30K26119+242#5811#5569
30K → 20M12415+109#5569#5460
20M → 21M1583+155#5460#5305
21M → 35K779+68#5305#5237
35K → 23M13717+120#5237#5117
23M → 24M8215+67#5117#5050
24M → 40K3458-24#5050#5074
40K → 25.2M2211+11#5074#5063
25.2M → Finish4740+7#5063#5056
TOTALS1858440+1418
📊

Passing Visuals

Category:

📈Position Graph

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🎨Heatmap Timeline

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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