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BOSTON MARATHON 2023

Katsumi Sato

Bib: 31836•M

0:00
0:00
/ mi
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Overall
#0 / 26622
Gender (Male)
#0 / 15176
Division (M18-39)
#0 / 5285
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
9:40/mi
30:01
↑ 97↓ 3451.5%
10K· 6.21 mi
8:04/mi
55:06
↑ 79↓ 1380.4%
15K· 9.32 mi
8:16/mi
1:20:47
↑ 67↓ 78
20K· 12.43 mi
7:51/mi
1:45:09
↑ 106↓ 860.1%
Half· 13.11 mi
7:53/mi
1:50:32
↑ 19↓ 370.5%
25K· 15.53 mi
8:30/mi
2:11:09
↑ 66↓ 880.2%
30K· 18.64 mi
9:20/mi
2:40:08
↑ 181↓ 1480.2%
20M
10:22/mi
2:54:13
↑ 64↓ 500.2%
21M
12:23/mi
3:06:36
↑ 106↓ 241.6%
35K· 21.75 mi
10:38/mi
3:14:33
↑ 17↓ 861.7%
23M
11:41/mi
3:29:11
↑ 23↓ 630.6%
24M
15:08/mi
3:44:19
↓ 821.3%
40K· 24.85 mi
15:56/mi
3:57:56
↓ 200.3%
25.2M
16:14/mi
4:03:32
↑ 13↓ 160.2%
Finish· 26.22 mi
13:40/mi
4:17:28
↑ 22↓ 21

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:50:32
Pace8:26 /mi
2nd Half
Distance13.11 mi
Time2:26:56
Pace11:13 /mi
📊Positive Split: 32.9% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi11:51:4530:019:4030:01
9:40
-
10K
6.21 mi12:16:5055:068:5225:05
8:04
-1:36
15K
9.32 mi12:42:311:20:478:4025:41
8:16
+0:12
20K
12.43 mi13:06:531:45:098:2824:22
7:51
-0:25
Half
13.11 mi13:12:161:50:328:265:23
7:53
+0:02
25K
15.53 mi13:32:532:11:098:2720:37
8:30
+0:37
30K
18.64 mi14:01:522:40:088:3528:59
9:20
+0:50
20M
20.00 mi14:15:572:54:138:4314:05
10:22
+1:02
21M
21.00 mi14:28:203:06:368:5312:23
12:23
+2:01
35K
21.75 mi14:36:173:14:338:577:57
10:38
-1:45
23M
23.00 mi14:50:553:29:119:0614:38
11:41
+1:03
24M
24.00 mi15:06:033:44:199:2115:08
15:08
+3:27
40K
24.85 mi15:19:403:57:569:3413:37
15:56
+0:48
25.2M
25.20 mi15:25:164:03:329:405:36
16:14
+0:18
Finish
26.22 mi15:39:124:17:289:5013:56
13:40
-2:34

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

7:51 /mi

Average Pace

9:50 /mi

Slowest Pace

16:14 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

1:41:08

39% of race

Time at Steady Pace

1:35:40

37% of race

Time at Slower Pace

1:00:40

24% of race

Average Pace: 9:49 /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 mi11:51:4530:019:4030:01
9:40
#22541
10K
6.21 mi12:16:5055:068:5225:05
8:04
#20025
15K
9.32 mi12:42:311:20:478:4025:41
8:16
#18852
20K
12.43 mi13:06:531:45:098:2824:22
7:51
#17328
Half
13.11 mi13:12:161:50:328:265:23
7:53
#17146
25K
15.53 mi13:32:532:11:098:2720:37
8:30
#16988
30K
18.64 mi14:01:522:40:088:3528:59
9:20
#17299
20M
20.00 mi14:15:572:54:138:4314:05
10:22
#17782
21M
21.00 mi14:28:203:06:368:5312:23
12:23
#18461
35K
21.75 mi14:36:173:14:338:577:57
10:38
#18726
23M
23.00 mi14:50:553:29:119:0614:38
11:41
#19271
24M
24.00 mi15:06:033:44:199:2115:08
15:08
#20231
40K
24.85 mi15:19:403:57:569:3413:37
15:56
#20858
25.2M
25.20 mi15:25:164:03:329:405:36
16:14
#21090
Finish
26.22 mi15:39:124:17:289:5013:56
13:40
#21575
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM18-39Seg. OverallSeg. MalesSeg. M18-39
5K3.11 mi3.11 mi22541133641336416321(Top 61%)10816(Top 71%)10816(Top 205%)
10K6.21 mi3.10 mi20025+251612225+113912225+113915325(Top 58%)10442(Top 69%)10442(Top 198%)
15K9.32 mi3.11 mi18852+117311794+43111794+43116321(Top 61%)10816(Top 71%)10816(Top 205%)
20K12.43 mi3.11 mi17328+152411182+61211182+61212095(Top 45%)9060(Top 60%)9060(Top 171%)
Half13.11 mi0.68 mi17146+18211115+6711115+6713502(Top 51%)9707(Top 64%)9707(Top 184%)
25K15.53 mi2.42 mi16988+15811032+8311032+8316217(Top 61%)10632(Top 70%)10632(Top 201%)
30K18.64 mi3.11 mi17299-31111142-11011142-11018745(Top 70%)11673(Top 77%)11673(Top 221%)
20M20.00 mi1.36 mi17782-48311313-17111313-17121424(Top 80%)12750(Top 84%)12750(Top 241%)
21M21.00 mi1.00 mi18461-67911582-26911582-26923301(Top 88%)13574(Top 89%)13574(Top 257%)
35K21.75 mi0.75 mi18726-26511693-11111693-11122616(Top 85%)13213(Top 87%)13213(Top 250%)
23M23.00 mi1.25 mi19271-54511917-22411917-22423546(Top 88%)13649(Top 90%)13649(Top 258%)
24M24.00 mi1.00 mi20231-96012304-38712304-38726412(Top 99%)15050(Top 99%)15050(Top 285%)
40K24.85 mi0.85 mi20858-62712564-26012564-26026391(Top 99%)15034(Top 99%)15034(Top 284%)
25.2M25.20 mi0.35 mi21090-23212658-9412658-9426178(Top 98%)14909(Top 98%)14909(Top 282%)
Finish26.22 mi1.02 mi21575-48512874-21612874-21626253(Top 99%)14937(Top 98%)14937(Top 283%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 61%
×21story building
+97ft-345ft

Overall

16321

Males

10816

M18-39

10816

5K→10K

3.1 - 6.2 mi

Top 58%
×5story building
+79ft-138ft

Overall

15325

Males

10442

M18-39

10442

10K→15K

6.2 - 9.3 mi

Top 61%
×3story building
+67ft-78ft

Overall

16321

Males

10816

M18-39

10816

15K→20K

9.3 - 12.4 mi

Top 45%
×5story building
+106ft-86ft

Overall

12095

Males

9060

M18-39

9060

20K→Half

12.4 - 13.1 mi

Top 51%
×2story building
+19ft-37ft

Overall

13502

Males

9707

M18-39

9707

Half→25K

13.1 - 15.5 mi

Top 61%
×4story building
+66ft-88ft

Overall

16217

Males

10632

M18-39

10632

25K→30K

15.5 - 18.6 mi

Top 70%
×9story building
+181ft-148ft

Overall

18745

Males

11673

M18-39

11673

30K→20M

18.6 - 20.0 mi

Top 80%
×5story building
+64ft-50ft

Overall

21424

Males

12750

M18-39

12750

20M→21M

20.0 - 21.0 mi

Top 88%
×8story building
+106ft-24ft

Overall

23301

Males

13574

M18-39

13574

21M→35K

21.0 - 21.8 mi

Top 85%
×7story building
+17ft-86ft

Overall

22616

Males

13213

M18-39

13213

35K→23M

21.8 - 23.0 mi

Top 88%
×5story building
+23ft-63ft

Overall

23546

Males

13649

M18-39

13649

23M→24M

23.0 - 24.0 mi

Top 99%
×6story building
+12ft-82ft

Overall

26412

Males

15050

M18-39

15050

24M→40K

24.0 - 24.9 mi

Top 99%
×1story
+6ft-20ft

Overall

26391

Males

15034

M18-39

15034

40K→25.2M

24.9 - 25.2 mi

Top 98%
×1story
+13ft-16ft

Overall

26178

Males

14909

M18-39

14909

25.2M→Finish

25.2 - 26.2 mi

Top 99%
×2story building
+22ft-21ft

Overall

26253

Males

14937

M18-39

14937

Passing Analysis

Category:
Athletes Passed
5733
Passed By
4767
Net Change
+966
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#22541
5K → 10K25171+2516#22541#20025
10K → 15K11796+1173#20025#18852
15K → 20K15251+1524#18852#17328
20K → Half1820+182#17328#17146
Half → 25K20143+158#17146#16988
25K → 30K94405-311#16988#17299
30K → 20M14497-483#17299#17782
20M → 21M5684-679#17782#18461
21M → 35K9274-265#18461#18726
35K → 23M7552-545#18726#19271
23M → 24M0960-960#19271#20231
24M → 40K0627-627#20231#20858
40K → 25.2M0232-232#20858#21090
25.2M → Finish0485-485#21090#21575
TOTALS57334767+966
📊

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