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BOSTON MARATHON 2025

Brenna Erzen

Bib: 27156•X

NH

0:00
0:00
/ mi
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Overall
#0 / 28404
Gender (Other)
#0 / 71
Race Day Weather
50°/40°F
broken clouds

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
30:25
Rank: #25066
Start → 5K
30:25 | 9:47/mi
10K· 6.21 mi
1:00:25
Rank: #24790 (+276)
5K → 10K
30:00 | 9:39/mi
15K· 9.32 mi
1:30:20
Rank: #24563 (+227)
10K → 15K
29:55 | 9:38/mi
20K· 12.43 mi
2:01:10
Rank: #24409 (+154)
15K → 20K
30:50 | 9:55/mi
Half· 13.11 mi
2:07:51
Rank: #24413 (-4)
20K → Half
6:41 | 9:48/mi
25K· 15.53 mi
2:32:43
Rank: #24327 (+86)
Half → 25K
24:52 | 10:15/mi
30K· 18.64 mi
3:06:58
Rank: #24296 (+31)
25K → 30K
34:15 | 11:01/mi
20M
3:21:45
Rank: #24218 (+78)
30K → 20M
14:47 | 10:53/mi
21M
3:32:17
Rank: #24019 (+199)
20M → 21M
10:32 | 10:32/mi
35K· 21.75 mi
3:39:32
Rank: #23904 (+115)
21M → 35K
7:15 | 9:41/mi
23M
3:52:04
Rank: #23722 (+182)
35K → 23M
12:32 | 10:01/mi
24M
4:01:42
Rank: #23583 (+139)
23M → 24M
9:38 | 9:38/mi
40K· 24.85 mi
4:10:08
Rank: #23454 (+129)
24M → 40K
8:26 | 9:52/mi
25.2M
4:13:48
Rank: #23382 (+72)
40K → 25.2M
3:40 | 10:38/mi
Finish· 26.22 mi
4:23:30
Rank: #23330 (+52)
25.2M → Finish
9:42 | 9:31/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time2:07:51
Pace9:45 /mi
2nd Half
Distance13.11 mi
Time2:15:39
Pace10:21 /mi
📊Positive Split: 6.1% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi11:50:5230:259:4730:25
9:47
-
10K
6.21 mi12:20:521:00:259:4330:00
9:39
-0:08
15K
9.32 mi12:50:471:30:209:4229:55
9:38
-0:01
20K
12.43 mi13:21:372:01:109:4530:50
9:55
+0:17
Half
13.11 mi13:28:182:07:519:456:41
9:48
-0:07
25K
15.53 mi13:53:102:32:439:5024:52
10:15
+0:27
30K
18.64 mi14:27:253:06:5810:0234:15
11:01
+0:46
20M
20.00 mi14:42:123:21:4510:0514:47
10:53
-0:08
21M
21.00 mi14:52:443:32:1710:0710:32
10:32
-0:21
35K
21.75 mi14:59:593:39:3210:067:15
9:41
-0:51
23M
23.00 mi15:12:313:52:0410:0512:32
10:01
+0:20
24M
24.00 mi15:22:094:01:4210:049:38
9:38
-0:23
40K
24.85 mi15:30:354:10:0810:048:26
9:52
+0:14
25.2M
25.20 mi15:34:154:13:4810:043:40
10:38
+0:46
Finish
26.22 mi15:43:574:23:3010:039:42
9:31
-1:07

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

9:31 /mi

Average Pace

10:03 /mi

Slowest Pace

11:01 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

3:20:16

76% of race

Time at Steady Pace

1:03:14

24% of race

Time at Slower Pace

0:00

0% of race

Average Pace: 10:03 /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 mi11:50:5230:259:4730:25
9:47
#25066
10K
6.21 mi12:20:521:00:259:4330:00
9:39
#24790
15K
9.32 mi12:50:471:30:209:4229:55
9:38
#24563
20K
12.43 mi13:21:372:01:109:4530:50
9:55
#24409
Half
13.11 mi13:28:182:07:519:456:41
9:48
#24413
25K
15.53 mi13:53:102:32:439:5024:52
10:15
#24327
30K
18.64 mi14:27:253:06:5810:0234:15
11:01
#24296
20M
20.00 mi14:42:123:21:4510:0514:47
10:53
#24218
21M
21.00 mi14:52:443:32:1710:0710:32
10:32
#24019
35K
21.75 mi14:59:593:39:3210:067:15
9:41
#23904
23M
23.00 mi15:12:313:52:0410:0512:32
10:01
#23722
24M
24.00 mi15:22:094:01:4210:049:38
9:38
#23583
40K
24.85 mi15:30:354:10:0810:048:26
9:52
#23454
25.2M
25.20 mi15:34:154:13:4810:043:40
10:38
#23382
Finish
26.22 mi15:43:574:23:3010:039:42
9:31
#23330
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallXAge DivSeg. OverallSeg. XSeg. Age Div
5K3.11 mi3.11 mi25066646424092(Top 85%)64(Top 90%)64
10K6.21 mi3.10 mi24790+276646424494(Top 86%)64(Top 90%)64
15K9.32 mi3.11 mi24563+227646424092(Top 85%)64(Top 90%)64
20K12.43 mi3.11 mi24409+154646424072(Top 85%)63(Top 89%)63
Half13.11 mi0.68 mi24413-4646424348(Top 86%)63(Top 89%)63
25K15.53 mi2.42 mi24327+86646423839(Top 84%)61(Top 86%)61
30K18.64 mi3.11 mi24296+3163+163+124036(Top 85%)63(Top 89%)63
20M20.00 mi1.36 mi24218+78636323320(Top 82%)59(Top 83%)59
21M21.00 mi1.00 mi24019+19962+162+120087(Top 71%)53(Top 75%)53
35K21.75 mi0.75 mi23904+115626220942(Top 74%)53(Top 75%)53
23M23.00 mi1.25 mi23722+182626220504(Top 72%)50(Top 70%)50
24M24.00 mi1.00 mi23583+139626220095(Top 71%)50(Top 70%)50
40K24.85 mi0.85 mi23454+129626219973(Top 70%)51(Top 72%)51
25.2M25.20 mi0.35 mi23382+72626219385(Top 68%)53(Top 75%)53
Finish26.22 mi1.02 mi23330+52626221223(Top 75%)54(Top 76%)54

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 85%
×21stories
+97ft-345ft

Overall

24092

X

64

Age Div

64

5K→10K

3.1 - 6.2 mi

Top 86%
×5stories
+79ft-138ft

Overall

24494

X

64

Age Div

64

10K→15K

6.2 - 9.3 mi

Top 85%
×3stories
+67ft-78ft

Overall

24092

X

64

Age Div

64

15K→20K

9.3 - 12.4 mi

Top 85%
×5stories
+106ft-86ft

Overall

24072

X

63

Age Div

63

20K→Half

12.4 - 13.1 mi

Top 86%
×2stories
+19ft-37ft

Overall

24348

X

63

Age Div

63

Half→25K

13.1 - 15.5 mi

Top 84%
×4stories
+66ft-88ft

Overall

23839

X

61

Age Div

61

25K→30K

15.5 - 18.6 mi

Top 85%
×9stories
+181ft-148ft

Overall

24036

X

63

Age Div

63

30K→20M

18.6 - 20.0 mi

Top 82%
×5stories
+64ft-50ft

Overall

23320

X

59

Age Div

59

20M→21M

20.0 - 21.0 mi

Top 71%
×8stories
+106ft-24ft

Overall

20087

X

53

Age Div

53

21M→35K

21.0 - 21.8 mi

Top 74%
×7stories
+17ft-86ft

Overall

20942

X

53

Age Div

53

35K→23M

21.8 - 23.0 mi

Top 72%
×5stories
+23ft-63ft

Overall

20504

X

50

Age Div

50

23M→24M

23.0 - 24.0 mi

Top 71%
×6stories
+12ft-82ft

Overall

20095

X

50

Age Div

50

24M→40K

24.0 - 24.9 mi

Top 70%
×1story
+6ft-20ft

Overall

19973

X

51

Age Div

51

40K→25.2M

24.9 - 25.2 mi

Top 68%
×1story
+13ft-16ft

Overall

19385

X

53

Age Div

53

25.2M→Finish

25.2 - 26.2 mi

Top 75%
×2stories
+22ft-21ft

Overall

21223

X

54

Age Div

54

Passing Analysis

Category:
Athletes Passed
2217
Passed By
481
Net Change
+1736
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#25066
5K → 10K36791+276#25066#24790
10K → 15K26740+227#24790#24563
15K → 20K20854+154#24563#24409
20K → Half2226-4#24409#24413
Half → 25K15973+86#24413#24327
25K → 30K159128+31#24327#24296
30K → 20M11133+78#24296#24218
20M → 21M2023+199#24218#24019
21M → 35K1205+115#24019#23904
35K → 23M1853+182#23904#23722
23M → 24M1412+139#23722#23583
24M → 40K1323+129#23583#23454
40K → 25.2M753+72#23454#23382
25.2M → Finish6917+52#23382#23330
TOTALS2217481+1736
📊

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