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BOSTON MARATHON 2023

Chihiro Nakai

Bib: 16030•F

AL

0:00
0:00
/ mi
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Overall
#0 / 26622
Top 44%
Gender (Female)
#0 / 11423
Top 26%
Division (F18-39)
#0 / 4884
Top 43%
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
8:15/mi
25:39
↑ 97↓ 3451.5%
10K· 6.21 mi
7:54/mi
50:12
↑ 79↓ 1380.4%
15K· 9.32 mi
7:54/mi
1:14:45
↑ 67↓ 78
20K· 12.43 mi
7:52/mi
1:39:12
↑ 106↓ 860.1%
Half· 13.11 mi
7:34/mi
1:44:22
↑ 19↓ 370.5%
25K· 15.53 mi
7:45/mi
2:03:10
↑ 66↓ 880.2%
30K· 18.64 mi
7:57/mi
2:27:51
↑ 181↓ 1480.2%
20M
8:06/mi
2:38:51
↑ 64↓ 500.2%
21M
8:37/mi
2:47:28
↑ 106↓ 241.6%
35K· 21.75 mi
7:46/mi
2:53:17
↑ 17↓ 861.7%
23M
7:51/mi
3:03:07
↑ 23↓ 630.6%
24M
7:41/mi
3:10:48
↓ 821.3%
40K· 24.85 mi
7:58/mi
3:17:37
↓ 200.3%
25.2M
8:39/mi
3:20:36
↑ 13↓ 160.2%
Finish· 26.22 mi
7:29/mi
3:28:14
↑ 22↓ 21

The Course

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Half Splits

1st Half· via Half⚖️ Balanced
Distance13.11 mi
Time1:44:22
Pace7:58 /mi
2nd Half⚖️ Balanced
Distance13.11 mi
Time1:43:52
Pace7:55 /mi
📊Even Split: Consistent pacing between halves

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi11:21:3925:398:1525:39
8:15
-
10K
6.21 mi11:46:1250:128:0524:33
7:54
-0:21
15K
9.32 mi12:10:451:14:458:0124:33
7:54
0:00
20K
12.43 mi12:35:121:39:127:5924:27
7:52
-0:02
Half
13.11 mi12:40:221:44:227:585:10
7:34
-0:18
25K
15.53 mi12:59:102:03:107:5618:48
7:45
+0:11
30K
18.64 mi13:23:512:27:517:5624:41
7:57
+0:12
20M
20.00 mi13:34:512:38:517:5711:00
8:06
+0:09
21M
21.00 mi13:43:282:47:287:588:37
8:37
+0:31
35K
21.75 mi13:49:172:53:177:585:49
7:46
-0:51
23M
23.00 mi13:59:073:03:077:589:50
7:51
+0:05
24M
24.00 mi14:06:483:10:487:577:41
7:41
-0:10
40K
24.85 mi14:13:373:17:377:576:49
7:58
+0:17
25.2M
25.20 mi14:16:363:20:367:582:59
8:39
+0:41
Finish
26.22 mi14:24:143:28:147:577:38
7:29
-1:10

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

7:29 /mi

Average Pace

7:57 /mi

Slowest Pace

8:39 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

2:50:59

82% of race

Time at Steady Pace

37:15

18% of race

Time at Slower Pace

0:00

0% of race

Average Pace: 7:57 /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 mi11:21:3925:398:1525:39
8:15
#15854
10K
6.21 mi11:46:1250:128:0524:33
7:54
#14962
15K
9.32 mi12:10:451:14:458:0124:33
7:54
#14493
20K
12.43 mi12:35:121:39:127:5924:27
7:52
#13956
Half
13.11 mi12:40:221:44:227:585:10
7:34
#13792
25K
15.53 mi12:59:102:03:107:5618:48
7:45
#13297
30K
18.64 mi13:23:512:27:517:5624:41
7:57
#12746
20M
20.00 mi13:34:512:38:517:5711:00
8:06
#12570
21M
21.00 mi13:43:282:47:287:588:37
8:37
#12440
35K
21.75 mi13:49:172:53:177:585:49
7:46
#12376
23M
23.00 mi13:59:073:03:077:589:50
7:51
#12148
24M
24.00 mi14:06:483:10:487:577:41
7:41
#11990
40K
24.85 mi14:13:373:17:377:576:49
7:58
#11892
25.2M
25.20 mi14:16:363:20:367:582:59
8:39
#11864
Finish
26.22 mi14:24:143:28:147:577:38
7:29
#11693
Faster pace
Steady pace
Slower pace
Est.Checkpoint not recorded (estimated)
~Segment time uses estimated prior

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallFemalesF18-39Seg. OverallSeg. FemalesSeg. F18-39
5K3.11 mi3.11 mi158545179517913560(Top 51%)3807(Top 33%)3807(Top 78%)
10K6.21 mi3.10 mi14962+8924626+5534626+55314009(Top 53%)4048(Top 35%)4048(Top 83%)
15K9.32 mi3.11 mi14493+4694348+2784348+27813560(Top 51%)3807(Top 33%)3807(Top 78%)
20K12.43 mi3.11 mi13956+5374058+2904058+29012346(Top 46%)3162(Top 28%)3162(Top 65%)
Half13.11 mi0.68 mi13792+1643955+1033955+10310899(Top 41%)2328(Top 20%)2328(Top 48%)
25K15.53 mi2.42 mi13297+4953679+2763679+27610759(Top 40%)2372(Top 21%)2372(Top 49%)
30K18.64 mi3.11 mi12746+5513399+2803399+28010487(Top 39%)2385(Top 21%)2385(Top 49%)
20M20.00 mi1.36 mi12570+1763312+873312+8711006(Top 41%)2739(Top 24%)2739(Top 56%)
21M21.00 mi1.00 mi12440+1303261+513261+5111179(Top 42%)2961(Top 26%)2961(Top 61%)
35K21.75 mi0.75 mi12376+643239+223239+2210532(Top 40%)2632(Top 23%)2632(Top 54%)
23M23.00 mi1.25 mi12148+2283137+1023137+1028794(Top 33%)1941(Top 17%)1941(Top 40%)
24M24.00 mi1.00 mi11990+1583071+663071+669027(Top 34%)2121(Top 19%)2121(Top 43%)
40K24.85 mi0.85 mi11892+983032+393032+399912(Top 37%)2610(Top 23%)2610(Top 53%)
25.2M25.20 mi0.35 mi11864+283025+73025+710522(Top 40%)2948(Top 26%)2948(Top 60%)
Finish26.22 mi1.02 mi11693+1712954+712954+718526(Top 32%)2047(Top 18%)2047(Top 42%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 51%
×21story building
+97ft-345ft

Overall

13560

Females

3807

F18-39

3807

5K→10K

3.1 - 6.2 mi

Top 53%
×5story building
+79ft-138ft

Overall

14009

Females

4048

F18-39

4048

10K→15K

6.2 - 9.3 mi

Top 51%
×3story building
+67ft-78ft

Overall

13560

Females

3807

F18-39

3807

15K→20K

9.3 - 12.4 mi

Top 46%
×5story building
+106ft-86ft

Overall

12346

Females

3162

F18-39

3162

20K→Half

12.4 - 13.1 mi

Top 41%
×2story building
+19ft-37ft

Overall

10899

Females

2328

F18-39

2328

Half→25K

13.1 - 15.5 mi

Top 40%
×4story building
+66ft-88ft

Overall

10759

Females

2372

F18-39

2372

25K→30K

15.5 - 18.6 mi

Top 39%
×9story building
+181ft-148ft

Overall

10487

Females

2385

F18-39

2385

30K→20M

18.6 - 20.0 mi

Top 41%
×5story building
+64ft-50ft

Overall

11006

Females

2739

F18-39

2739

20M→21M

20.0 - 21.0 mi

Top 42%
×8story building
+106ft-24ft

Overall

11179

Females

2961

F18-39

2961

21M→35K

21.0 - 21.8 mi

Top 40%
×7story building
+17ft-86ft

Overall

10532

Females

2632

F18-39

2632

35K→23M

21.8 - 23.0 mi

Top 33%
×5story building
+23ft-63ft

Overall

8794

Females

1941

F18-39

1941

23M→24M

23.0 - 24.0 mi

Top 34%
×6story building
+12ft-82ft

Overall

9027

Females

2121

F18-39

2121

24M→40K

24.0 - 24.9 mi

Top 37%
×1story
+6ft-20ft

Overall

9912

Females

2610

F18-39

2610

40K→25.2M

24.9 - 25.2 mi

Top 40%
×1story
+13ft-16ft

Overall

10522

Females

2948

F18-39

2948

25.2M→Finish

25.2 - 26.2 mi

Top 32%
×2story building
+22ft-21ft

Overall

8526

Females

2047

F18-39

2047

Passing Analysis

Category:
Athletes Passed
4428
Passed By
267
Net Change
+4161
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#15854
5K → 10K94957+892#15854#14962
10K → 15K50839+469#14962#14493
15K → 20K54811+537#14493#13956
20K → Half1651+164#13956#13792
Half → 25K4994+495#13792#13297
25K → 30K56514+551#13297#12746
30K → 20M20226+176#12746#12570
20M → 21M15929+130#12570#12440
21M → 35K8824+64#12440#12376
35K → 23M2324+228#12376#12148
23M → 24M17012+158#12148#11990
24M → 40K11416+98#11990#11892
40K → 25.2M4517+28#11892#11864
25.2M → Finish18413+171#11864#11693
TOTALS4428267+4161
📊

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