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BOSTON MARATHON 2023

Bon Sok Koo

Bib: 23878•M

ON

0:00
0:00
/ mi
Masters
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Overall
#0 / 26622
Gender (Male)
#0 / 15176
Masters (Masters Men)
#0 / 9891
Division (M65-69)
#0 / 549
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
8:37/mi
26:47
↑ 97↓ 3451.5%
10K· 6.21 mi
8:42/mi
53:48
↑ 79↓ 1380.4%
15K· 9.32 mi
8:44/mi
1:20:55
↑ 67↓ 78
20K· 12.43 mi
8:52/mi
1:48:28
↑ 106↓ 860.1%
Half· 13.11 mi
8:52/mi
1:54:31
↑ 19↓ 370.5%
25K· 15.53 mi
9:04/mi
2:16:30
↑ 66↓ 880.2%
30K· 18.64 mi
9:34/mi
2:46:12
↑ 181↓ 1480.2%
20M
10:31/mi
3:00:30
↑ 64↓ 500.2%
21M
13:16/mi
3:13:46
↑ 106↓ 241.6%
35K· 21.75 mi
10:46/mi
3:21:49
↑ 17↓ 861.7%
23M
11:50/mi
3:36:38
↑ 23↓ 630.6%
24M
11:03/mi
3:47:41
↓ 821.3%
40K· 24.85 mi
11:48/mi
3:57:46
↓ 200.3%
25.2M
12:08/mi
4:01:57
↑ 13↓ 160.2%
Finish· 26.22 mi
11:19/mi
4:13:29
↑ 22↓ 21

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:54:31
Pace8:44 /mi
2nd Half
Distance13.11 mi
Time2:18:58
Pace10:36 /mi
📊Positive Split: 21.4% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi11:41:4926:478:3726:47
8:37
-
10K
6.21 mi12:08:5053:488:3927:01
8:42
+0:05
15K
9.32 mi12:35:571:20:558:4127:07
8:44
+0:02
20K
12.43 mi13:03:301:48:288:4427:33
8:52
+0:08
Half
13.11 mi13:09:331:54:318:446:03
8:52
0:00
25K
15.53 mi13:31:322:16:308:4721:59
9:04
+0:12
30K
18.64 mi14:01:142:46:128:5529:42
9:34
+0:30
20M
20.00 mi14:15:323:00:309:0114:18
10:31
+0:57
21M
21.00 mi14:28:483:13:469:1413:16
13:16
+2:45
35K
21.75 mi14:36:513:21:499:178:03
10:46
-2:30
23M
23.00 mi14:51:403:36:389:2514:49
11:50
+1:04
24M
24.00 mi15:02:433:47:419:2911:03
11:03
-0:47
40K
24.85 mi15:12:483:57:469:3410:05
11:48
+0:45
25.2M
25.20 mi15:16:594:01:579:364:11
12:08
+0:20
Finish
26.22 mi15:28:314:13:299:4011:32
11:19
-0:49

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

8:37 /mi

Average Pace

9:40 /mi

Slowest Pace

13:16 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

2:46:12

66% of race

Time at Steady Pace

33:24

13% of race

Time at Slower Pace

53:53

21% of race

Average Pace: 9:40 /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 mi11:41:4926:478:3726:47
8:37
#18345
10K
6.21 mi12:08:5053:488:3927:01
8:42
#18860
15K
9.32 mi12:35:571:20:558:4127:07
8:44
#18938
20K
12.43 mi13:03:301:48:288:4427:33
8:52
#18948
Half
13.11 mi13:09:331:54:318:446:03
8:52
#19002
25K
15.53 mi13:31:322:16:308:4721:59
9:04
#19021
30K
18.64 mi14:01:142:46:128:5529:42
9:34
#19188
20M
20.00 mi14:15:323:00:309:0114:18
10:31
#19479
21M
21.00 mi14:28:483:13:469:1413:16
13:16
#20063
35K
21.75 mi14:36:513:21:499:178:03
10:46
#20219
23M
23.00 mi14:51:403:36:389:2514:49
11:50
#20528
24M
24.00 mi15:02:433:47:419:2911:03
11:03
#20692
40K
24.85 mi15:12:483:57:469:3410:05
11:48
#20836
25.2M
25.20 mi15:16:594:01:579:364:11
12:08
#20875
Finish
26.22 mi15:28:314:13:299:4011:32
11:19
#21090
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM65-69Seg. OverallSeg. MalesSeg. M65-69
5K3.11 mi3.11 mi18345115501155019120(Top 72%)11930(Top 79%)11930(Top 2173%)
10K6.21 mi3.10 mi18860-51511792-24211792-24219399(Top 73%)12065(Top 80%)12065(Top 2198%)
15K9.32 mi3.11 mi18938-7811826-3411826-3419120(Top 72%)11930(Top 79%)11930(Top 2173%)
20K12.43 mi3.11 mi18948-1011837-1111837-1119044(Top 72%)11913(Top 78%)11913(Top 2170%)
Half13.11 mi0.68 mi19002-5411857-2011857-2019832(Top 74%)12245(Top 81%)12245(Top 2230%)
25K15.53 mi2.42 mi19021-1911869-1211869-1219273(Top 72%)11962(Top 79%)11962(Top 2179%)
30K18.64 mi3.11 mi19188-16711918-4911918-4919657(Top 74%)12072(Top 80%)12072(Top 2199%)
20M20.00 mi1.36 mi19479-29112020-10212020-10221778(Top 82%)12896(Top 85%)12896(Top 2349%)
21M21.00 mi1.00 mi20063-58412260-24012260-24024356(Top 91%)14059(Top 93%)14059(Top 2561%)
35K21.75 mi0.75 mi20219-15612314-5412314-5422835(Top 86%)13304(Top 88%)13304(Top 2423%)
23M23.00 mi1.25 mi20528-30912440-12612440-12623767(Top 89%)13756(Top 91%)13756(Top 2506%)
24M24.00 mi1.00 mi20692-16412501-6112501-6123135(Top 87%)13407(Top 88%)13407(Top 2442%)
40K24.85 mi0.85 mi20836-14412551-5012551-5023621(Top 89%)13593(Top 90%)13593(Top 2476%)
25.2M25.20 mi0.35 mi20875-3912564-1312564-1322708(Top 85%)13179(Top 87%)13179(Top 2401%)
Finish26.22 mi1.02 mi21090-21512647-8312647-8324440(Top 92%)14041(Top 93%)14041(Top 2558%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 72%
×21story building
+97ft-345ft

Overall

19120

Males

11930

M65-69

11930

5K→10K

3.1 - 6.2 mi

Top 73%
×5story building
+79ft-138ft

Overall

19399

Males

12065

M65-69

12065

10K→15K

6.2 - 9.3 mi

Top 72%
×3story building
+67ft-78ft

Overall

19120

Males

11930

M65-69

11930

15K→20K

9.3 - 12.4 mi

Top 72%
×5story building
+106ft-86ft

Overall

19044

Males

11913

M65-69

11913

20K→Half

12.4 - 13.1 mi

Top 74%
×2story building
+19ft-37ft

Overall

19832

Males

12245

M65-69

12245

Half→25K

13.1 - 15.5 mi

Top 72%
×4story building
+66ft-88ft

Overall

19273

Males

11962

M65-69

11962

25K→30K

15.5 - 18.6 mi

Top 74%
×9story building
+181ft-148ft

Overall

19657

Males

12072

M65-69

12072

30K→20M

18.6 - 20.0 mi

Top 82%
×5story building
+64ft-50ft

Overall

21778

Males

12896

M65-69

12896

20M→21M

20.0 - 21.0 mi

Top 91%
×8story building
+106ft-24ft

Overall

24356

Males

14059

M65-69

14059

21M→35K

21.0 - 21.8 mi

Top 86%
×7story building
+17ft-86ft

Overall

22835

Males

13304

M65-69

13304

35K→23M

21.8 - 23.0 mi

Top 89%
×5story building
+23ft-63ft

Overall

23767

Males

13756

M65-69

13756

23M→24M

23.0 - 24.0 mi

Top 87%
×6story building
+12ft-82ft

Overall

23135

Males

13407

M65-69

13407

24M→40K

24.0 - 24.9 mi

Top 89%
×1story
+6ft-20ft

Overall

23621

Males

13593

M65-69

13593

40K→25.2M

24.9 - 25.2 mi

Top 85%
×1story
+13ft-16ft

Overall

22708

Males

13179

M65-69

13179

25.2M→Finish

25.2 - 26.2 mi

Top 92%
×2story building
+22ft-21ft

Overall

24440

Males

14041

M65-69

14041

Passing Analysis

Category:
Athletes Passed
804
Passed By
3549
Net Change
-2745
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#18345
5K → 10K142657-515#18345#18860
10K → 15K147225-78#18860#18938
15K → 20K161171-10#18938#18948
20K → Half1367-54#18948#19002
Half → 25K122141-19#19002#19021
25K → 30K113280-167#19021#19188
30K → 20M31322-291#19188#19479
20M → 21M5589-584#19479#20063
21M → 35K16172-156#20063#20219
35K → 23M13322-309#20219#20528
23M → 24M13177-164#20528#20692
24M → 40K11155-144#20692#20836
40K → 25.2M443-39#20836#20875
25.2M → Finish13228-215#20875#21090
TOTALS8043549-2745
📊

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