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BOSTON MARATHON 2023

Won Il Kim

Bib: 4050•M

0:00
0:00
/ mi
Masters
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Overall
#0 / 26622
Top 13%
Gender (Male)
#0 / 15176
Top 22%
Masters (Masters Men)
#0 / 9891
Top 9%
Division (M50-54)
#0 / 2052
Top 5%
Race Day Weather
49°/39°F
light intensity drizzle

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
19:55
Rank: #1859
Start → 5K
19:55 | 6:25/mi
10K· 6.21 mi
40:10
Rank: #2306 (-447)
5K → 10K
20:15 | 6:31/mi
15K· 9.32 mi
1:00:45
Rank: #2637 (-331)
10K → 15K
20:35 | 6:38/mi
20K· 12.43 mi
1:21:40
Rank: #2880 (-243)
15K → 20K
20:55 | 6:44/mi
Half· 13.11 mi
1:26:12
Rank: #2920 (-40)
20K → Half
4:32 | 6:39/mi
25K· 15.53 mi
1:42:41
Rank: #3064 (-144)
Half → 25K
16:29 | 6:48/mi
30K· 18.64 mi
2:04:38
Rank: #3335 (-271)
25K → 30K
21:57 | 7:04/mi
20M
2:14:16
Rank: #3401 (-66)
30K → 20M
9:38 | 7:05/mi
21M
2:21:41
Rank: #3427 (-26)
20M → 21M
7:25 | 7:25/mi
35K· 21.75 mi
2:26:44
Rank: #3419 (+8)
21M → 35K
5:03 | 6:45/mi
23M
2:35:30
Rank: #3425 (-6)
35K → 23M
8:46 | 7:00/mi
24M
2:42:13
Rank: #3390 (+35)
23M → 24M
6:43 | 6:43/mi
40K· 24.85 mi
2:48:15
Rank: #3417 (-27)
24M → 40K
6:02 | 7:03/mi
25.2M
2:50:49
Rank: #3421 (-4)
40K → 25.2M
2:34 | 7:27/mi
Finish· 26.22 mi
2:57:57
Rank: #3473 (-52)
25.2M → Finish
7:08 | 7:00/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:26:12
Pace6:35 /mi
2nd Half
Distance13.11 mi
Time1:31:45
Pace7:00 /mi
📊Positive Split: 6.4% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:21:4219:556:2519:55
6:25
-
10K
6.21 mi10:41:5740:106:2820:15
6:31
+0:06
15K
9.32 mi11:02:321:00:456:3120:35
6:38
+0:07
20K
12.43 mi11:23:271:21:406:3420:55
6:44
+0:06
Half
13.11 mi11:27:591:26:126:354:32
6:39
-0:05
25K
15.53 mi11:44:281:42:416:3716:29
6:48
+0:09
30K
18.64 mi12:06:252:04:386:4121:57
7:04
+0:16
20M
20.00 mi12:16:032:14:166:439:38
7:05
+0:01
21M
21.00 mi12:23:282:21:416:457:25
7:25
+0:20
35K
21.75 mi12:28:312:26:446:455:03
6:45
-0:40
23M
23.00 mi12:37:172:35:306:468:46
7:00
+0:15
24M
24.00 mi12:44:002:42:136:466:43
6:43
-0:17
40K
24.85 mi12:50:022:48:156:466:02
7:03
+0:20
25.2M
25.20 mi12:52:362:50:496:472:34
7:27
+0:24
Finish
26.22 mi12:59:442:57:576:487:08
7:00
-0:27

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

6:25 /mi

Average Pace

6:48 /mi

Slowest Pace

7:27 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

2:16:23

77% of race

Time at Steady Pace

41:34

23% of race

Time at Slower Pace

0:00

0% of race

Average Pace: 6:47 /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 mi10:21:4219:556:2519:55
6:25
#1859
10K
6.21 mi10:41:5740:106:2820:15
6:31
#2306
15K
9.32 mi11:02:321:00:456:3120:35
6:38
#2637
20K
12.43 mi11:23:271:21:406:3420:55
6:44
#2880
Half
13.11 mi11:27:591:26:126:354:32
6:39
#2920
25K
15.53 mi11:44:281:42:416:3716:29
6:48
#3064
30K
18.64 mi12:06:252:04:386:4121:57
7:04
#3335
20M
20.00 mi12:16:032:14:166:439:38
7:05
#3401
21M
21.00 mi12:23:282:21:416:457:25
7:25
#3427
35K
21.75 mi12:28:312:26:446:455:03
6:45
#3419
23M
23.00 mi12:37:172:35:306:468:46
7:00
#3425
24M
24.00 mi12:44:002:42:136:466:43
6:43
#3390
40K
24.85 mi12:50:022:48:156:466:02
7:03
#3417
25.2M
25.20 mi12:52:362:50:496:472:34
7:27
#3421
Finish
26.22 mi12:59:442:57:576:487:08
7:00
#3473
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM50-54Seg. OverallSeg. MalesSeg. M50-54
5K3.11 mi3.11 mi1859177417743507(Top 13%)3321(Top 22%)3321(Top 162%)
10K6.21 mi3.10 mi2306-4472204-4302204-4302910(Top 11%)2780(Top 18%)2780(Top 135%)
15K9.32 mi3.11 mi2637-3312518-3142518-3143507(Top 13%)3321(Top 22%)3321(Top 162%)
20K12.43 mi3.11 mi2880-2432750-2322750-2323816(Top 14%)3598(Top 24%)3598(Top 175%)
Half13.11 mi0.68 mi2920-402788-382788-383774(Top 14%)3558(Top 23%)3558(Top 173%)
25K15.53 mi2.42 mi3064-1442922-1342922-1344110(Top 15%)3850(Top 25%)3850(Top 188%)
30K18.64 mi3.11 mi3335-2713165-2433165-2434733(Top 18%)4367(Top 29%)4367(Top 213%)
20M20.00 mi1.36 mi3401-663221-563221-564522(Top 17%)4147(Top 27%)4147(Top 202%)
21M21.00 mi1.00 mi3427-263245-243245-244176(Top 16%)3828(Top 25%)3828(Top 187%)
35K21.75 mi0.75 mi3419+83236+93236+93845(Top 14%)3539(Top 23%)3539(Top 172%)
23M23.00 mi1.25 mi3425-63241-53241-53790(Top 14%)3497(Top 23%)3497(Top 170%)
24M24.00 mi1.00 mi3390+353207+343207+343196(Top 12%)2962(Top 20%)2962(Top 144%)
40K24.85 mi0.85 mi3417-273228-213228-214119(Top 15%)3680(Top 24%)3680(Top 179%)
25.2M25.20 mi0.35 mi3421-43231-33231-33595(Top 14%)3223(Top 21%)3223(Top 157%)
Finish26.22 mi1.02 mi3473-523273-423273-425169(Top 19%)4377(Top 29%)4377(Top 213%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 13%
×21stories
+97ft-345ft

Overall

3507

Males

3321

M50-54

3321

5K→10K

3.1 - 6.2 mi

Top 11%
×5stories
+79ft-138ft

Overall

2910

Males

2780

M50-54

2780

10K→15K

6.2 - 9.3 mi

Top 13%
×3stories
+67ft-78ft

Overall

3507

Males

3321

M50-54

3321

15K→20K

9.3 - 12.4 mi

Top 14%
×5stories
+106ft-86ft

Overall

3816

Males

3598

M50-54

3598

20K→Half

12.4 - 13.1 mi

Top 14%
×2stories
+19ft-37ft

Overall

3774

Males

3558

M50-54

3558

Half→25K

13.1 - 15.5 mi

Top 15%
×4stories
+66ft-88ft

Overall

4110

Males

3850

M50-54

3850

25K→30K

15.5 - 18.6 mi

Top 18%
×9stories
+181ft-148ft

Overall

4733

Males

4367

M50-54

4367

30K→20M

18.6 - 20.0 mi

Top 17%
×5stories
+64ft-50ft

Overall

4522

Males

4147

M50-54

4147

20M→21M

20.0 - 21.0 mi

Top 16%
×8stories
+106ft-24ft

Overall

4176

Males

3828

M50-54

3828

21M→35K

21.0 - 21.8 mi

Top 14%
×7stories
+17ft-86ft

Overall

3845

Males

3539

M50-54

3539

35K→23M

21.8 - 23.0 mi

Top 14%
×5stories
+23ft-63ft

Overall

3790

Males

3497

M50-54

3497

23M→24M

23.0 - 24.0 mi

Top 12%
×6stories
+12ft-82ft

Overall

3196

Males

2962

M50-54

2962

24M→40K

24.0 - 24.9 mi

Top 15%
×1story
+6ft-20ft

Overall

4119

Males

3680

M50-54

3680

40K→25.2M

24.9 - 25.2 mi

Top 14%
×1story
+13ft-16ft

Overall

3595

Males

3223

M50-54

3223

25.2M→Finish

25.2 - 26.2 mi

Top 19%
×2stories
+22ft-21ft

Overall

5169

Males

4377

M50-54

4377

Passing Analysis

Category:
Athletes Passed
414
Passed By
2028
Net Change
-1614
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#1859
5K → 10K12459-447#1859#2306
10K → 15K5336-331#2306#2637
15K → 20K24267-243#2637#2880
20K → Half444-40#2880#2920
Half → 25K25169-144#2920#3064
25K → 30K31302-271#3064#3335
30K → 20M37103-66#3335#3401
20M → 21M5076-26#3401#3427
21M → 35K3426+8#3427#3419
35K → 23M5561-6#3419#3425
23M → 24M5722+35#3425#3390
24M → 40K3259-27#3390#3417
40K → 25.2M1620-4#3417#3421
25.2M → Finish3284-52#3421#3473
TOTALS4142028-1614
📊

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