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BOSTON MARATHON 2023

Ken Tsai

Bib: 15000•M

CA

0:00
0:00
/ mi
Masters
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Overall
#0 / 26622
Gender (Male)
#0 / 15176
Masters (Masters Men)
#0 / 9891
Division (M50-54)
#0 / 2052
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
7:50/mi
24:19
↑ 97↓ 3451.5%
10K· 6.21 mi
7:53/mi
48:48
↑ 79↓ 1380.4%
15K· 9.32 mi
7:57/mi
1:13:30
↑ 67↓ 78
20K· 12.43 mi
8:10/mi
1:38:53
↑ 106↓ 860.1%
Half· 13.11 mi
8:04/mi
1:44:23
↑ 19↓ 370.5%
25K· 15.53 mi
8:29/mi
2:04:58
↑ 66↓ 880.2%
30K· 18.64 mi
8:52/mi
2:32:32
↑ 181↓ 1480.2%
20M
8:56/mi
2:44:40
↑ 64↓ 500.2%
21M
10:01/mi
2:54:41
↑ 106↓ 241.6%
35K· 21.75 mi
8:53/mi
3:01:20
↑ 17↓ 861.7%
23M
9:02/mi
3:12:38
↑ 23↓ 630.6%
24M
8:52/mi
3:21:30
↓ 821.3%
40K· 24.85 mi
8:52/mi
3:29:05
↓ 200.3%
25.2M
9:25/mi
3:32:20
↑ 13↓ 160.2%
Finish· 26.22 mi
8:25/mi
3:40:55
↑ 22↓ 21

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:44:23
Pace7:58 /mi
2nd Half
Distance13.11 mi
Time1:56:32
Pace8:53 /mi
📊Positive Split: 11.6% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:54:2124:197:5024:19
7:50
-
10K
6.21 mi11:18:5048:487:5124:29
7:53
+0:03
15K
9.32 mi11:43:321:13:307:5324:42
7:57
+0:04
20K
12.43 mi12:08:551:38:537:5725:23
8:10
+0:13
Half
13.11 mi12:14:251:44:237:585:30
8:04
-0:06
25K
15.53 mi12:35:002:04:588:0320:35
8:29
+0:25
30K
18.64 mi13:02:342:32:328:1127:34
8:52
+0:23
20M
20.00 mi13:14:422:44:408:1412:08
8:56
+0:04
21M
21.00 mi13:24:432:54:418:1910:01
10:01
+1:05
35K
21.75 mi13:31:223:01:208:206:39
8:53
-1:08
23M
23.00 mi13:42:403:12:388:2311:18
9:02
+0:09
24M
24.00 mi13:51:323:21:308:248:52
8:52
-0:10
40K
24.85 mi13:59:073:29:058:257:35
8:52
0:00
25.2M
25.20 mi14:02:223:32:208:263:15
9:25
+0:33
Finish
26.22 mi14:10:573:40:558:268:35
8:25
-1:00

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

7:50 /mi

Average Pace

8:26 /mi

Slowest Pace

10:01 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

2:13:33

60% of race

Time at Steady Pace

1:14:06

34% of race

Time at Slower Pace

13:16

6% of race

Average Pace: 8:26 /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 mi10:54:2124:197:5024:19
7:50
#12606
10K
6.21 mi11:18:5048:487:5124:29
7:53
#13211
15K
9.32 mi11:43:321:13:307:5324:42
7:57
#13454
20K
12.43 mi12:08:551:38:537:5725:23
8:10
#13749
Half
13.11 mi12:14:251:44:237:585:30
8:04
#13800
25K
15.53 mi12:35:002:04:588:0320:35
8:29
#14239
30K
18.64 mi13:02:342:32:328:1127:34
8:52
#14675
20M
20.00 mi13:14:422:44:408:1412:08
8:56
#14801
21M
21.00 mi13:24:432:54:418:1910:01
10:01
#15009
35K
21.75 mi13:31:223:01:208:206:39
8:53
#15094
23M
23.00 mi13:42:403:12:388:2311:18
9:02
#15124
24M
24.00 mi13:51:323:21:308:248:52
8:52
#15176
40K
24.85 mi13:59:073:29:058:257:35
8:52
#15193
25.2M
25.20 mi14:02:223:32:208:263:15
9:25
#15170
Finish
26.22 mi14:10:573:40:558:268:35
8:25
#15162
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM50-54Seg. OverallSeg. MalesSeg. M50-54
5K3.11 mi3.11 mi126069374937413991(Top 53%)9896(Top 65%)9896(Top 482%)
10K6.21 mi3.10 mi13211-6059624-2509624-25013804(Top 52%)9862(Top 65%)9862(Top 481%)
15K9.32 mi3.11 mi13454-2439715-919715-9113991(Top 53%)9896(Top 65%)9896(Top 482%)
20K12.43 mi3.11 mi13749-2959795-809795-8014745(Top 55%)10174(Top 67%)10174(Top 496%)
Half13.11 mi0.68 mi13800-519821-269821-2614804(Top 56%)10221(Top 67%)10221(Top 498%)
25K15.53 mi2.42 mi14239-4399969-1489969-14816109(Top 61%)10578(Top 70%)10578(Top 515%)
30K18.64 mi3.11 mi14675-43610117-14810117-14816489(Top 62%)10684(Top 70%)10684(Top 521%)
20M20.00 mi1.36 mi14801-12610143-2610143-2616142(Top 61%)10465(Top 69%)10465(Top 510%)
21M21.00 mi1.00 mi15009-20810190-4710190-4718071(Top 68%)11242(Top 74%)11242(Top 548%)
35K21.75 mi0.75 mi15094-8510201-1110201-1117353(Top 65%)10852(Top 72%)10852(Top 529%)
23M23.00 mi1.25 mi15124-3010190+1110190+1116163(Top 61%)10310(Top 68%)10310(Top 502%)
24M24.00 mi1.00 mi15176-5210194-410194-416549(Top 62%)10421(Top 69%)10421(Top 508%)
40K24.85 mi0.85 mi15193-1710185+910185+915437(Top 58%)9870(Top 65%)9870(Top 481%)
25.2M25.20 mi0.35 mi15170+2310161+2410161+2414765(Top 55%)9569(Top 63%)9569(Top 466%)
Finish26.22 mi1.02 mi15162+810135+2610135+2614873(Top 56%)9668(Top 64%)9668(Top 471%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 53%
×21story building
+97ft-345ft

Overall

13991

Males

9896

M50-54

9896

5K→10K

3.1 - 6.2 mi

Top 52%
×5story building
+79ft-138ft

Overall

13804

Males

9862

M50-54

9862

10K→15K

6.2 - 9.3 mi

Top 53%
×3story building
+67ft-78ft

Overall

13991

Males

9896

M50-54

9896

15K→20K

9.3 - 12.4 mi

Top 55%
×5story building
+106ft-86ft

Overall

14745

Males

10174

M50-54

10174

20K→Half

12.4 - 13.1 mi

Top 56%
×2story building
+19ft-37ft

Overall

14804

Males

10221

M50-54

10221

Half→25K

13.1 - 15.5 mi

Top 61%
×4story building
+66ft-88ft

Overall

16109

Males

10578

M50-54

10578

25K→30K

15.5 - 18.6 mi

Top 62%
×9story building
+181ft-148ft

Overall

16489

Males

10684

M50-54

10684

30K→20M

18.6 - 20.0 mi

Top 61%
×5story building
+64ft-50ft

Overall

16142

Males

10465

M50-54

10465

20M→21M

20.0 - 21.0 mi

Top 68%
×8story building
+106ft-24ft

Overall

18071

Males

11242

M50-54

11242

21M→35K

21.0 - 21.8 mi

Top 65%
×7story building
+17ft-86ft

Overall

17353

Males

10852

M50-54

10852

35K→23M

21.8 - 23.0 mi

Top 61%
×5story building
+23ft-63ft

Overall

16163

Males

10310

M50-54

10310

23M→24M

23.0 - 24.0 mi

Top 62%
×6story building
+12ft-82ft

Overall

16549

Males

10421

M50-54

10421

24M→40K

24.0 - 24.9 mi

Top 58%
×1story
+6ft-20ft

Overall

15437

Males

9870

M50-54

9870

40K→25.2M

24.9 - 25.2 mi

Top 55%
×1story
+13ft-16ft

Overall

14765

Males

9569

M50-54

9569

25.2M→Finish

25.2 - 26.2 mi

Top 56%
×2story building
+22ft-21ft

Overall

14873

Males

9668

M50-54

9668

Passing Analysis

Category:
Athletes Passed
875
Passed By
3431
Net Change
-2556
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#12606
5K → 10K114719-605#12606#13211
10K → 15K122365-243#13211#13454
15K → 20K100395-295#13454#13749
20K → Half1566-51#13749#13800
Half → 25K45484-439#13800#14239
25K → 30K74510-436#14239#14675
30K → 20M48174-126#14675#14801
20M → 21M37245-208#14801#15009
21M → 35K28113-85#15009#15094
35K → 23M6999-30#15094#15124
23M → 24M49101-52#15124#15176
24M → 40K5269-17#15176#15193
40K → 25.2M5128+23#15193#15170
25.2M → Finish7163+8#15170#15162
TOTALS8753431-2556
📊

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