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BOSTON MARATHON 2023

Kok Seng Tan

Bib: 29851•M

0:00
0:00
/ mi
Masters
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Overall
#0 / 26622
Gender (Male)
#0 / 15176
Masters (Masters Men)
#0 / 9891
Division (M55-59)
#0 / 1422
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
8:42/mi
27:03
↑ 97↓ 3451.5%
10K· 6.21 mi
8:21/mi
53:01
↑ 79↓ 1380.4%
15K· 9.32 mi
8:27/mi
1:19:16
↑ 67↓ 78
20K· 12.43 mi
8:42/mi
1:46:18
↑ 106↓ 860.1%
Half· 13.11 mi
8:49/mi
1:52:19
↑ 19↓ 370.5%
25K· 15.53 mi
9:07/mi
2:14:25
↑ 66↓ 880.2%
30K· 18.64 mi
9:29/mi
2:43:53
↑ 181↓ 1480.2%
20M
9:22/mi
2:56:37
↑ 64↓ 500.2%
21M
10:01/mi
3:06:38
↑ 106↓ 241.6%
35K· 21.75 mi
9:07/mi
3:13:27
↑ 17↓ 861.7%
23M
9:27/mi
3:25:17
↑ 23↓ 630.6%
24M
9:21/mi
3:34:38
↓ 821.3%
40K· 24.85 mi
9:26/mi
3:42:42
↓ 200.3%
25.2M
10:03/mi
3:46:10
↑ 13↓ 160.2%
Finish· 26.22 mi
9:07/mi
3:55:27
↑ 22↓ 21

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:52:19
Pace8:34 /mi
2nd Half
Distance13.11 mi
Time2:03:08
Pace9:24 /mi
📊Positive Split: 9.6% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi11:45:1127:038:4227:03
8:42
-
10K
6.21 mi12:11:0953:018:3225:58
8:21
-0:21
15K
9.32 mi12:37:241:19:168:3026:15
8:27
+0:06
20K
12.43 mi13:04:261:46:188:3327:02
8:42
+0:15
Half
13.11 mi13:10:271:52:198:346:01
8:49
+0:07
25K
15.53 mi13:32:332:14:258:3922:06
9:07
+0:18
30K
18.64 mi14:02:012:43:538:4729:28
9:29
+0:22
20M
20.00 mi14:14:452:56:378:5012:44
9:22
-0:07
21M
21.00 mi14:24:463:06:388:5310:01
10:01
+0:39
35K
21.75 mi14:31:353:13:278:546:49
9:07
-0:54
23M
23.00 mi14:43:253:25:178:5611:50
9:27
+0:20
24M
24.00 mi14:52:463:34:388:579:21
9:21
-0:06
40K
24.85 mi15:00:503:42:428:588:04
9:26
+0:05
25.2M
25.20 mi15:04:183:46:108:583:28
10:03
+0:37
Finish
26.22 mi15:13:353:55:278:599:17
9:07
-0:56

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

10:03 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

1:52:19

48% of race

Time at Steady Pace

47:33

20% of race

Time at Slower Pace

1:15:35

32% 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 mi11:45:1127:038:4227:03
8:42
#18927
10K
6.21 mi12:11:0953:018:3225:58
8:21
#18097
15K
9.32 mi12:37:241:19:168:3026:15
8:27
#17880
20K
12.43 mi13:04:261:46:188:3327:02
8:42
#17910
Half
13.11 mi13:10:271:52:198:346:01
8:49
#18002
25K
15.53 mi13:32:332:14:258:3922:06
9:07
#18286
30K
18.64 mi14:02:012:43:538:4729:28
9:29
#18527
20M
20.00 mi14:14:452:56:378:5012:44
9:22
#18503
21M
21.00 mi14:24:463:06:388:5310:01
10:01
#18470
35K
21.75 mi14:31:353:13:278:546:49
9:07
#18461
23M
23.00 mi14:43:253:25:178:5611:50
9:27
#18442
24M
24.00 mi14:52:463:34:388:579:21
9:21
#18467
40K
24.85 mi15:00:503:42:428:588:04
9:26
#18448
25.2M
25.20 mi15:04:183:46:108:583:28
10:03
#18437
Finish
26.22 mi15:13:353:55:278:599:17
9:07
#18452
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM55-59Seg. OverallSeg. MalesSeg. M55-59
5K3.11 mi3.11 mi18927117501175017452(Top 66%)11246(Top 74%)11246(Top 791%)
10K6.21 mi3.10 mi18097+83011492+25811492+25817284(Top 65%)11214(Top 74%)11214(Top 789%)
15K9.32 mi3.11 mi17880+21711406+8611406+8617452(Top 66%)11246(Top 74%)11246(Top 791%)
20K12.43 mi3.11 mi17910-3011418-1211418-1218124(Top 68%)11524(Top 76%)11524(Top 810%)
Half13.11 mi0.68 mi18002-9211468-5011468-5019551(Top 73%)12114(Top 80%)12114(Top 852%)
25K15.53 mi2.42 mi18286-28411568-10011568-10019479(Top 73%)12044(Top 79%)12044(Top 847%)
30K18.64 mi3.11 mi18527-24111622-5411622-5419365(Top 73%)11948(Top 79%)11948(Top 840%)
20M20.00 mi1.36 mi18503+2411611+1111611+1118314(Top 69%)11381(Top 75%)11381(Top 800%)
21M21.00 mi1.00 mi18470+3311586+2511586+2518086(Top 68%)11257(Top 74%)11257(Top 792%)
35K21.75 mi0.75 mi18461+911574+1211574+1218363(Top 69%)11309(Top 75%)11309(Top 795%)
23M23.00 mi1.25 mi18442+1911549+2511549+2518126(Top 68%)11170(Top 74%)11170(Top 786%)
24M24.00 mi1.00 mi18467-2511559-1011559-1018638(Top 70%)11373(Top 75%)11373(Top 800%)
40K24.85 mi0.85 mi18448+1911536+2311536+2318077(Top 68%)11073(Top 73%)11073(Top 779%)
25.2M25.20 mi0.35 mi18437+1111527+911527+917564(Top 66%)10821(Top 71%)10821(Top 761%)
Finish26.22 mi1.02 mi18452-1511524+311524+318494(Top 69%)11307(Top 75%)11307(Top 795%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 66%
×21story building
+97ft-345ft

Overall

17452

Males

11246

M55-59

11246

5K→10K

3.1 - 6.2 mi

Top 65%
×5story building
+79ft-138ft

Overall

17284

Males

11214

M55-59

11214

10K→15K

6.2 - 9.3 mi

Top 66%
×3story building
+67ft-78ft

Overall

17452

Males

11246

M55-59

11246

15K→20K

9.3 - 12.4 mi

Top 68%
×5story building
+106ft-86ft

Overall

18124

Males

11524

M55-59

11524

20K→Half

12.4 - 13.1 mi

Top 73%
×2story building
+19ft-37ft

Overall

19551

Males

12114

M55-59

12114

Half→25K

13.1 - 15.5 mi

Top 73%
×4story building
+66ft-88ft

Overall

19479

Males

12044

M55-59

12044

25K→30K

15.5 - 18.6 mi

Top 73%
×9story building
+181ft-148ft

Overall

19365

Males

11948

M55-59

11948

30K→20M

18.6 - 20.0 mi

Top 69%
×5story building
+64ft-50ft

Overall

18314

Males

11381

M55-59

11381

20M→21M

20.0 - 21.0 mi

Top 68%
×8story building
+106ft-24ft

Overall

18086

Males

11257

M55-59

11257

21M→35K

21.0 - 21.8 mi

Top 69%
×7story building
+17ft-86ft

Overall

18363

Males

11309

M55-59

11309

35K→23M

21.8 - 23.0 mi

Top 68%
×5story building
+23ft-63ft

Overall

18126

Males

11170

M55-59

11170

23M→24M

23.0 - 24.0 mi

Top 70%
×6story building
+12ft-82ft

Overall

18638

Males

11373

M55-59

11373

24M→40K

24.0 - 24.9 mi

Top 68%
×1story
+6ft-20ft

Overall

18077

Males

11073

M55-59

11073

40K→25.2M

24.9 - 25.2 mi

Top 66%
×1story
+13ft-16ft

Overall

17564

Males

10821

M55-59

10821

25.2M→Finish

25.2 - 26.2 mi

Top 69%
×2story building
+22ft-21ft

Overall

18494

Males

11307

M55-59

11307

Passing Analysis

Category:
Athletes Passed
2128
Passed By
1653
Net Change
+475
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#18927
5K → 10K949119+830#18927#18097
10K → 15K31699+217#18097#17880
15K → 20K154184-30#17880#17910
20K → Half14106-92#17910#18002
Half → 25K59343-284#18002#18286
25K → 30K111352-241#18286#18527
30K → 20M10379+24#18527#18503
20M → 21M10269+33#18503#18470
21M → 35K5344+9#18470#18461
35K → 23M9374+19#18461#18442
23M → 24M3964-25#18442#18467
24M → 40K6445+19#18467#18448
40K → 25.2M3221+11#18448#18437
25.2M → Finish3954-15#18437#18452
TOTALS21281653+475
📊

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