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BOSTON MARATHON 2025

Brenna Lorenzen

Bib: 31408•F

MA

0:00
0:00
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Overall
#0 / 28404
Gender (Female)
#0 / 12228
Division (F18-39)
#0 / 5469
Race Day Weather
50°/40°F
broken clouds

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
33:41
Rank: #27344
Start → 5K
33:41 | 10:50/mi
10K· 6.21 mi
1:07:19
Rank: #27084 (+260)
5K → 10K
33:38 | 10:50/mi
15K· 9.32 mi
1:41:03
Rank: #26856 (+228)
10K → 15K
33:44 | 10:51/mi
20K· 12.43 mi
2:15:53
Rank: #26688 (+168)
15K → 20K
34:50 | 11:13/mi
Half· 13.11 mi
2:23:25
Rank: #26677 (+11)
20K → Half
7:32 | 11:02/mi
25K· 15.53 mi
2:57:36
Rank: #27048 (-371)
Half → 25K
34:11 | 14:06/mi
30K· 18.64 mi
3:37:19
Rank: #26970 (+78)
25K → 30K
39:43 | 12:47/mi
20M
3:53:39
Rank: #26876 (+94)
30K → 20M
16:20 | 12:01/mi
21M
4:07:44
Rank: #26870 (+6)
20M → 21M
14:05 | 14:05/mi
35K· 21.75 mi
4:16:40
Rank: #26827 (+43)
21M → 35K
8:56 | 11:56/mi
23M
4:32:22
Rank: #26794 (+33)
35K → 23M
15:42 | 12:32/mi
24M
4:43:59
Rank: #26733 (+61)
23M → 24M
11:37 | 11:37/mi
40K· 24.85 mi
4:53:55
Rank: #26671 (+62)
24M → 40K
9:56 | 11:37/mi
25.2M
4:58:29
Rank: #26656 (+15)
40K → 25.2M
4:34 | 13:15/mi
Finish· 26.22 mi
5:09:36
Rank: #26630 (+26)
25.2M → Finish
11:07 | 10:55/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time2:23:25
Pace10:56 /mi
2nd Half
Distance13.11 mi
Time2:46:11
Pace12:41 /mi
📊Positive Split: 15.9% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi11:56:5433:4110:5033:41
10:50
-
10K
6.21 mi12:30:321:07:1910:5033:38
10:50
0:00
15K
9.32 mi13:04:161:41:0310:5033:44
10:51
+0:01
20K
12.43 mi13:39:062:15:5310:5634:50
11:13
+0:22
Half
13.11 mi13:46:382:23:2510:567:32
11:02
-0:11
25K
15.53 mi14:20:492:57:3611:2634:11
14:06
+3:04
30K
18.64 mi15:00:323:37:1911:3939:43
12:47
-1:19
20M
20.00 mi15:16:523:53:3911:4116:20
12:01
-0:46
21M
21.00 mi15:30:574:07:4411:4814:05
14:05
+2:04
35K
21.75 mi15:39:534:16:4011:488:56
11:56
-2:09
23M
23.00 mi15:55:354:32:2211:5115:42
12:32
+0:36
24M
24.00 mi16:07:124:43:5911:5011:37
11:37
-0:55
40K
24.85 mi16:17:084:53:5511:509:56
11:37
0:00
25.2M
25.20 mi16:21:424:58:2911:514:34
13:15
+1:38
Finish
26.22 mi16:32:495:09:3611:4911:07
10:55
-2:20

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

10:50 /mi

Average Pace

11:49 /mi

Slowest Pace

14:06 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

1:59:42

39% of race

Time at Steady Pace

1:21:39

26% of race

Time at Slower Pace

1:48:15

35% of race

Average Pace: 11:48 /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 mi11:56:5433:4110:5033:41
10:50
#27344
10K
6.21 mi12:30:321:07:1910:5033:38
10:50
#27084
15K
9.32 mi13:04:161:41:0310:5033:44
10:51
#26856
20K
12.43 mi13:39:062:15:5310:5634:50
11:13
#26688
Half
13.11 mi13:46:382:23:2510:567:32
11:02
#26677
25K
15.53 mi14:20:492:57:3611:2634:11
14:06
#27048
30K
18.64 mi15:00:323:37:1911:3939:43
12:47
#26970
20M
20.00 mi15:16:523:53:3911:4116:20
12:01
#26876
21M
21.00 mi15:30:574:07:4411:4814:05
14:05
#26870
35K
21.75 mi15:39:534:16:4011:488:56
11:56
#26827
23M
23.00 mi15:55:354:32:2211:5115:42
12:32
#26794
24M
24.00 mi16:07:124:43:5911:5011:37
11:37
#26733
40K
24.85 mi16:17:084:53:5511:509:56
11:37
#26671
25.2M
25.20 mi16:21:424:58:2911:514:34
13:15
#26656
Finish
26.22 mi16:32:495:09:3611:4911:07
10:55
#26630
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 mi27344115351153526488(Top 93%)11060(Top 90%)11060(Top 202%)
10K6.21 mi3.10 mi27084+26011401+13411401+13426815(Top 94%)11249(Top 92%)11249(Top 206%)
15K9.32 mi3.11 mi26856+22811270+13111270+13126488(Top 93%)11060(Top 90%)11060(Top 202%)
20K12.43 mi3.11 mi26688+16811171+9911171+9926302(Top 93%)10975(Top 90%)10975(Top 201%)
Half13.11 mi0.68 mi26677+1111163+811163+826545(Top 93%)11148(Top 91%)11148(Top 204%)
25K15.53 mi2.42 mi27048-37111412-24911412-24927929(Top 98%)11967(Top 98%)11967(Top 219%)
30K18.64 mi3.11 mi26970+7811375+3711375+3726460(Top 93%)11206(Top 92%)11206(Top 205%)
20M20.00 mi1.36 mi26876+9411335+4011335+4025289(Top 89%)10634(Top 87%)10634(Top 194%)
21M21.00 mi1.00 mi26870+611338-311338-326304(Top 93%)11211(Top 92%)11211(Top 205%)
35K21.75 mi0.75 mi26827+4311320+1811320+1825761(Top 91%)10986(Top 90%)10986(Top 201%)
23M23.00 mi1.25 mi26794+3311311+911311+925839(Top 91%)11023(Top 90%)11023(Top 202%)
24M24.00 mi1.00 mi26733+6111290+2111290+2125077(Top 88%)10668(Top 87%)10668(Top 195%)
40K24.85 mi0.85 mi26671+6211262+2811262+2824343(Top 86%)10349(Top 85%)10349(Top 189%)
25.2M25.20 mi0.35 mi26656+1511256+611256+625328(Top 89%)10862(Top 89%)10862(Top 199%)
Finish26.22 mi1.02 mi26630+2611249+711249+725180(Top 89%)10741(Top 88%)10741(Top 196%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 93%
×21stories
+97ft-345ft

Overall

26488

Females

11060

F18-39

11060

5K→10K

3.1 - 6.2 mi

Top 94%
×5stories
+79ft-138ft

Overall

26815

Females

11249

F18-39

11249

10K→15K

6.2 - 9.3 mi

Top 93%
×3stories
+67ft-78ft

Overall

26488

Females

11060

F18-39

11060

15K→20K

9.3 - 12.4 mi

Top 93%
×5stories
+106ft-86ft

Overall

26302

Females

10975

F18-39

10975

20K→Half

12.4 - 13.1 mi

Top 93%
×2stories
+19ft-37ft

Overall

26545

Females

11148

F18-39

11148

Half→25K

13.1 - 15.5 mi

Top 98%
×4stories
+66ft-88ft

Overall

27929

Females

11967

F18-39

11967

25K→30K

15.5 - 18.6 mi

Top 93%
×9stories
+181ft-148ft

Overall

26460

Females

11206

F18-39

11206

30K→20M

18.6 - 20.0 mi

Top 89%
×5stories
+64ft-50ft

Overall

25289

Females

10634

F18-39

10634

20M→21M

20.0 - 21.0 mi

Top 93%
×8stories
+106ft-24ft

Overall

26304

Females

11211

F18-39

11211

21M→35K

21.0 - 21.8 mi

Top 91%
×7stories
+17ft-86ft

Overall

25761

Females

10986

F18-39

10986

35K→23M

21.8 - 23.0 mi

Top 91%
×5stories
+23ft-63ft

Overall

25839

Females

11023

F18-39

11023

23M→24M

23.0 - 24.0 mi

Top 88%
×6stories
+12ft-82ft

Overall

25077

Females

10668

F18-39

10668

24M→40K

24.0 - 24.9 mi

Top 86%
×1story
+6ft-20ft

Overall

24343

Females

10349

F18-39

10349

40K→25.2M

24.9 - 25.2 mi

Top 89%
×1story
+13ft-16ft

Overall

25328

Females

10862

F18-39

10862

25.2M→Finish

25.2 - 26.2 mi

Top 89%
×2stories
+22ft-21ft

Overall

25180

Females

10741

F18-39

10741

Passing Analysis

Category:
Athletes Passed
1321
Passed By
607
Net Change
+714
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#27344
5K → 10K30444+260#27344#27084
10K → 15K25123+228#27084#26856
15K → 20K18820+168#26856#26688
20K → Half3221+11#26688#26677
Half → 25K10381-371#26677#27048
25K → 30K11941+78#27048#26970
30K → 20M984+94#26970#26876
20M → 21M3226+6#26876#26870
21M → 35K507+43#26870#26827
35K → 23M4916+33#26827#26794
23M → 24M709+61#26794#26733
24M → 40K675+62#26733#26671
40K → 25.2M161+15#26671#26656
25.2M → Finish359+26#26656#26630
TOTALS1321607+714
📊

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