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BOSTON MARATHON 2025

Sachiko Iwasaki

Bib: 20336•F

CA

0:00
0:00
/ mi
Masters
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Overall
#0 / 28404
Gender (Female)
#0 / 12228
Top 44%
Masters (Masters Women)
#0 / 6759
Top 31%
Division (F45-49)
#0 / 1813
Top 37%
Race Day Weather
50°/40°F
broken clouds

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
24:04
Rank: #14368
Start → 5K
24:04 | 7:45/mi
10K· 6.21 mi
47:59
Rank: #14096 (+272)
5K → 10K
23:55 | 7:42/mi
15K· 9.32 mi
1:11:57
Rank: #13926 (+170)
10K → 15K
23:58 | 7:43/mi
20K· 12.43 mi
1:36:13
Rank: #13735 (+191)
15K → 20K
24:16 | 7:49/mi
Half· 13.11 mi
1:41:31
Rank: #13748 (-13)
20K → Half
5:18 | 7:46/mi
25K· 15.53 mi
2:00:43
Rank: #13637 (+111)
Half → 25K
19:12 | 7:55/mi
30K· 18.64 mi
2:27:00
Rank: #13771 (-134)
25K → 30K
26:17 | 8:28/mi
20M
2:39:01
Rank: #13921 (-150)
30K → 20M
12:01 | 8:51/mi
21M
2:49:10
Rank: #14318 (-397)
20M → 21M
10:09 | 10:09/mi
35K· 21.75 mi
2:55:59
Rank: #14523 (-205)
21M → 35K
6:49 | 9:07/mi
23M
3:08:01
Rank: #14841 (-318)
35K → 23M
12:02 | 9:37/mi
24M
3:17:23
Rank: #15057 (-216)
23M → 24M
9:22 | 9:22/mi
40K· 24.85 mi
3:25:57
Rank: #15353 (-296)
24M → 40K
8:34 | 10:01/mi
25.2M
3:29:47
Rank: #15461 (-108)
40K → 25.2M
3:50 | 11:07/mi
Finish· 26.22 mi
3:39:50
Rank: #15819 (-358)
25.2M → Finish
10:03 | 9:52/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:41:31
Pace7:45 /mi
2nd Half
Distance13.11 mi
Time1:58:19
Pace9:02 /mi
📊Positive Split: 16.5% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi11:16:5624:047:4524:04
7:45
-
10K
6.21 mi11:40:5147:597:4323:55
7:42
-0:03
15K
9.32 mi12:04:491:11:577:4323:58
7:43
+0:01
20K
12.43 mi12:29:051:36:137:4524:16
7:49
+0:06
Half
13.11 mi12:34:231:41:317:455:18
7:46
-0:03
25K
15.53 mi12:53:352:00:437:4619:12
7:55
+0:09
30K
18.64 mi13:19:522:27:007:5326:17
8:28
+0:33
20M
20.00 mi13:31:532:39:017:5712:01
8:51
+0:23
21M
21.00 mi13:42:022:49:108:0310:09
10:09
+1:18
35K
21.75 mi13:48:512:55:598:066:49
9:07
-1:02
23M
23.00 mi14:00:533:08:018:1012:02
9:37
+0:30
24M
24.00 mi14:10:153:17:238:139:22
9:22
-0:15
40K
24.85 mi14:18:493:25:578:178:34
10:01
+0:39
25.2M
25.20 mi14:22:393:29:478:193:50
11:07
+1:06
Finish
26.22 mi14:32:423:39:508:2310:03
9:52
-1:15

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

7:42 /mi

Average Pace

8:23 /mi

Slowest Pace

11:07 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

2:00:43

55% of race

Time at Steady Pace

54:29

25% of race

Time at Slower Pace

44:38

20% of race

Average Pace: 8:23 /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 mi11:16:5624:047:4524:04
7:45
#14368
10K
6.21 mi11:40:5147:597:4323:55
7:42
#14096
15K
9.32 mi12:04:491:11:577:4323:58
7:43
#13926
20K
12.43 mi12:29:051:36:137:4524:16
7:49
#13735
Half
13.11 mi12:34:231:41:317:455:18
7:46
#13748
25K
15.53 mi12:53:352:00:437:4619:12
7:55
#13637
30K
18.64 mi13:19:522:27:007:5326:17
8:28
#13771
20M
20.00 mi13:31:532:39:017:5712:01
8:51
#13921
21M
21.00 mi13:42:022:49:108:0310:09
10:09
#14318
35K
21.75 mi13:48:512:55:598:066:49
9:07
#14523
23M
23.00 mi14:00:533:08:018:1012:02
9:37
#14841
24M
24.00 mi14:10:153:17:238:139:22
9:22
#15057
40K
24.85 mi14:18:493:25:578:178:34
10:01
#15353
25.2M
25.20 mi14:22:393:29:478:193:50
11:07
#15461
Finish
26.22 mi14:32:423:39:508:2310:03
9:52
#15819
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallFemalesF45-49Seg. OverallSeg. FemalesSeg. F45-49
5K3.11 mi3.11 mi143684143414313664(Top 48%)3827(Top 31%)3827(Top 211%)
10K6.21 mi3.10 mi14096+2723997+1463997+14613904(Top 49%)3905(Top 32%)3905(Top 215%)
15K9.32 mi3.11 mi13926+1703926+713926+7113664(Top 48%)3827(Top 31%)3827(Top 211%)
20K12.43 mi3.11 mi13735+1913862+643862+6413381(Top 47%)3756(Top 31%)3756(Top 207%)
Half13.11 mi0.68 mi13748-133885-233885-2314105(Top 50%)4138(Top 34%)4138(Top 228%)
25K15.53 mi2.42 mi13637+1113839+463839+4613275(Top 47%)3818(Top 31%)3818(Top 211%)
30K18.64 mi3.11 mi13771-1343978-1393978-13914530(Top 51%)4649(Top 38%)4649(Top 256%)
20M20.00 mi1.36 mi13921-1504100-1224100-12215913(Top 56%)5540(Top 45%)5540(Top 306%)
21M21.00 mi1.00 mi14318-3974335-2354335-23518863(Top 66%)7261(Top 59%)7261(Top 400%)
35K21.75 mi0.75 mi14523-2054469-1344469-13418781(Top 66%)7332(Top 60%)7332(Top 404%)
23M23.00 mi1.25 mi14841-3184677-2084677-20819127(Top 67%)7571(Top 62%)7571(Top 418%)
24M24.00 mi1.00 mi15057-2164836-1594836-15919100(Top 67%)7593(Top 62%)7593(Top 419%)
40K24.85 mi0.85 mi15353-2965045-2095045-20920513(Top 72%)8409(Top 69%)8409(Top 464%)
25.2M25.20 mi0.35 mi15461-1085118-735118-7320996(Top 74%)8640(Top 71%)8640(Top 477%)
Finish26.22 mi1.02 mi15819-3585345-2275345-22722508(Top 79%)9413(Top 77%)9413(Top 519%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 48%
×21stories
+97ft-345ft

Overall

13664

Females

3827

F45-49

3827

5K→10K

3.1 - 6.2 mi

Top 49%
×5stories
+79ft-138ft

Overall

13904

Females

3905

F45-49

3905

10K→15K

6.2 - 9.3 mi

Top 48%
×3stories
+67ft-78ft

Overall

13664

Females

3827

F45-49

3827

15K→20K

9.3 - 12.4 mi

Top 47%
×5stories
+106ft-86ft

Overall

13381

Females

3756

F45-49

3756

20K→Half

12.4 - 13.1 mi

Top 50%
×2stories
+19ft-37ft

Overall

14105

Females

4138

F45-49

4138

Half→25K

13.1 - 15.5 mi

Top 47%
×4stories
+66ft-88ft

Overall

13275

Females

3818

F45-49

3818

25K→30K

15.5 - 18.6 mi

Top 51%
×9stories
+181ft-148ft

Overall

14530

Females

4649

F45-49

4649

30K→20M

18.6 - 20.0 mi

Top 56%
×5stories
+64ft-50ft

Overall

15913

Females

5540

F45-49

5540

20M→21M

20.0 - 21.0 mi

Top 66%
×8stories
+106ft-24ft

Overall

18863

Females

7261

F45-49

7261

21M→35K

21.0 - 21.8 mi

Top 66%
×7stories
+17ft-86ft

Overall

18781

Females

7332

F45-49

7332

35K→23M

21.8 - 23.0 mi

Top 67%
×5stories
+23ft-63ft

Overall

19127

Females

7571

F45-49

7571

23M→24M

23.0 - 24.0 mi

Top 67%
×6stories
+12ft-82ft

Overall

19100

Females

7593

F45-49

7593

24M→40K

24.0 - 24.9 mi

Top 72%
×1story
+6ft-20ft

Overall

20513

Females

8409

F45-49

8409

40K→25.2M

24.9 - 25.2 mi

Top 74%
×1story
+13ft-16ft

Overall

20996

Females

8640

F45-49

8640

25.2M→Finish

25.2 - 26.2 mi

Top 79%
×2stories
+22ft-21ft

Overall

22508

Females

9413

F45-49

9413

Passing Analysis

Category:
Athletes Passed
1721
Passed By
3172
Net Change
-1451
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#14368
5K → 10K428156+272#14368#14096
10K → 15K278108+170#14096#13926
15K → 20K307116+191#13926#13735
20K → Half3043-13#13735#13748
Half → 25K226115+111#13748#13637
25K → 30K205339-134#13637#13771
30K → 20M79229-150#13771#13921
20M → 21M35432-397#13921#14318
21M → 35K26231-205#14318#14523
35K → 23M37355-318#14523#14841
23M → 24M34250-216#14841#15057
24M → 40K18314-296#15057#15353
40K → 25.2M5113-108#15353#15461
25.2M → Finish13371-358#15461#15819
TOTALS17213172-1451
📊

Passing Visuals

Category:
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🔥Passing Intensity

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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