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BOSTON MARATHON 2025

Justin Lacoursiere

Bib: 3694•M

CT

0:00
0:00
/ mi
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Overall
#0 / 28404
Top 13%
Gender (Male)
#0 / 16105
Top 21%
Division (M18-39)
#0 / 5642
Top 45%
Race Day Weather
50°/40°F
broken clouds

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
20:43
Rank: #5153
Start → 5K
20:43 | 6:40/mi
10K· 6.21 mi
41:21
Rank: #4956 (+197)
5K → 10K
20:38 | 6:38/mi
15K· 9.32 mi
1:01:48
Rank: #4630 (+326)
10K → 15K
20:27 | 6:35/mi
20K· 12.43 mi
1:22:22
Rank: #4385 (+245)
15K → 20K
20:34 | 6:37/mi
Half· 13.11 mi
1:26:52
Rank: #4372 (+13)
20K → Half
4:30 | 6:36/mi
25K· 15.53 mi
1:42:54
Rank: #4169 (+203)
Half → 25K
16:02 | 6:37/mi
30K· 18.64 mi
2:04:02
Rank: #3971 (+198)
25K → 30K
21:08 | 6:48/mi
20M
2:13:23
Rank: #3897 (+74)
30K → 20M
9:21 | 6:53/mi
21M
2:20:36
Rank: #3817 (+80)
20M → 21M
7:13 | 7:13/mi
35K· 21.75 mi
2:25:43
Rank: #3824 (-7)
21M → 35K
5:07 | 6:50/mi
23M
2:34:32
Rank: #3799 (+25)
35K → 23M
8:49 | 7:03/mi
24M
2:41:17
Rank: #3751 (+48)
23M → 24M
6:45 | 6:45/mi
40K· 24.85 mi
2:47:19
Rank: #3748 (+3)
24M → 40K
6:02 | 7:03/mi
25.2M
2:49:53
Rank: #3715 (+33)
40K → 25.2M
2:34 | 7:27/mi
Finish· 26.22 mi
2:56:45
Rank: #3682 (+33)
25.2M → Finish
6:52 | 6:44/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:26:52
Pace6:38 /mi
2nd Half
Distance13.11 mi
Time1:29:53
Pace6:51 /mi
📊Positive Split: 3.5% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:23:3420:436:4020:43
6:40
-
10K
6.21 mi10:44:1241:216:3920:38
6:38
-0:02
15K
9.32 mi11:04:391:01:486:3820:27
6:35
-0:03
20K
12.43 mi11:25:131:22:226:3820:34
6:37
+0:02
Half
13.11 mi11:29:431:26:526:384:30
6:36
-0:01
25K
15.53 mi11:45:451:42:546:3716:02
6:37
+0:01
30K
18.64 mi12:06:532:04:026:3921:08
6:48
+0:11
20M
20.00 mi12:16:142:13:236:409:21
6:53
+0:05
21M
21.00 mi12:23:272:20:366:427:13
7:13
+0:20
35K
21.75 mi12:28:342:25:436:425:07
6:50
-0:23
23M
23.00 mi12:37:232:34:326:438:49
7:03
+0:13
24M
24.00 mi12:44:082:41:176:436:45
6:45
-0:18
40K
24.85 mi12:50:102:47:196:446:02
7:03
+0:18
25.2M
25.20 mi12:52:442:49:536:442:34
7:27
+0:24
Finish
26.22 mi12:59:362:56:456:456:52
6:44
-0:43

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

6:35 /mi

Average Pace

6:45 /mi

Slowest Pace

7:27 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

2:54:11

99% of race

Time at Steady Pace

2:34

1% of race

Time at Slower Pace

0:00

0% of race

Average Pace: 6:44 /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 mi10:23:3420:436:4020:43
6:40
#5153
10K
6.21 mi10:44:1241:216:3920:38
6:38
#4956
15K
9.32 mi11:04:391:01:486:3820:27
6:35
#4630
20K
12.43 mi11:25:131:22:226:3820:34
6:37
#4385
Half
13.11 mi11:29:431:26:526:384:30
6:36
#4372
25K
15.53 mi11:45:451:42:546:3716:02
6:37
#4169
30K
18.64 mi12:06:532:04:026:3921:08
6:48
#3971
20M
20.00 mi12:16:142:13:236:409:21
6:53
#3897
21M
21.00 mi12:23:272:20:366:427:13
7:13
#3817
35K
21.75 mi12:28:342:25:436:425:07
6:50
#3824
23M
23.00 mi12:37:232:34:326:438:49
7:03
#3799
24M
24.00 mi12:44:082:41:176:436:45
6:45
#3751
40K
24.85 mi12:50:102:47:196:446:02
7:03
#3748
25.2M
25.20 mi12:52:442:49:536:442:34
7:27
#3715
Finish
26.22 mi12:59:362:56:456:456:52
6:44
#3682
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM18-39Seg. OverallSeg. MalesSeg. M18-39
5K3.11 mi3.11 mi5153480148014086(Top 14%)3845(Top 24%)3845(Top 68%)
10K6.21 mi3.10 mi4956+1974622+1794622+1794781(Top 17%)4471(Top 28%)4471(Top 79%)
15K9.32 mi3.11 mi4630+3264336+2864336+2864086(Top 14%)3845(Top 24%)3845(Top 68%)
20K12.43 mi3.11 mi4385+2454117+2194117+2193820(Top 13%)3602(Top 22%)3602(Top 64%)
Half13.11 mi0.68 mi4372+134104+134104+134290(Top 15%)4012(Top 25%)4012(Top 71%)
25K15.53 mi2.42 mi4169+2033917+1873917+1873535(Top 12%)3332(Top 21%)3332(Top 59%)
30K18.64 mi3.11 mi3971+1983733+1843733+1843458(Top 12%)3216(Top 20%)3216(Top 57%)
20M20.00 mi1.36 mi3897+743660+733660+733370(Top 12%)3116(Top 19%)3116(Top 55%)
21M21.00 mi1.00 mi3817+803586+743586+743197(Top 11%)2945(Top 18%)2945(Top 52%)
35K21.75 mi0.75 mi3824-73588-23588-24290(Top 15%)3819(Top 24%)3819(Top 68%)
23M23.00 mi1.25 mi3799+253554+343554+343984(Top 14%)3554(Top 22%)3554(Top 63%)
24M24.00 mi1.00 mi3751+483503+513503+513209(Top 11%)2889(Top 18%)2889(Top 51%)
40K24.85 mi0.85 mi3748+33496+73496+74191(Top 15%)3628(Top 23%)3628(Top 64%)
25.2M25.20 mi0.35 mi3715+333461+353461+353111(Top 11%)2752(Top 17%)2752(Top 49%)
Finish26.22 mi1.02 mi3682+333426+353426+354098(Top 14%)3501(Top 22%)3501(Top 62%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 14%
×21stories
+97ft-345ft

Overall

4086

Males

3845

M18-39

3845

5K→10K

3.1 - 6.2 mi

Top 17%
×5stories
+79ft-138ft

Overall

4781

Males

4471

M18-39

4471

10K→15K

6.2 - 9.3 mi

Top 14%
×3stories
+67ft-78ft

Overall

4086

Males

3845

M18-39

3845

15K→20K

9.3 - 12.4 mi

Top 13%
×5stories
+106ft-86ft

Overall

3820

Males

3602

M18-39

3602

20K→Half

12.4 - 13.1 mi

Top 15%
×2stories
+19ft-37ft

Overall

4290

Males

4012

M18-39

4012

Half→25K

13.1 - 15.5 mi

Top 12%
×4stories
+66ft-88ft

Overall

3535

Males

3332

M18-39

3332

25K→30K

15.5 - 18.6 mi

Top 12%
×9stories
+181ft-148ft

Overall

3458

Males

3216

M18-39

3216

30K→20M

18.6 - 20.0 mi

Top 12%
×5stories
+64ft-50ft

Overall

3370

Males

3116

M18-39

3116

20M→21M

20.0 - 21.0 mi

Top 11%
×8stories
+106ft-24ft

Overall

3197

Males

2945

M18-39

2945

21M→35K

21.0 - 21.8 mi

Top 15%
×7stories
+17ft-86ft

Overall

4290

Males

3819

M18-39

3819

35K→23M

21.8 - 23.0 mi

Top 14%
×5stories
+23ft-63ft

Overall

3984

Males

3554

M18-39

3554

23M→24M

23.0 - 24.0 mi

Top 11%
×6stories
+12ft-82ft

Overall

3209

Males

2889

M18-39

2889

24M→40K

24.0 - 24.9 mi

Top 15%
×1story
+6ft-20ft

Overall

4191

Males

3628

M18-39

3628

40K→25.2M

24.9 - 25.2 mi

Top 11%
×1story
+13ft-16ft

Overall

3111

Males

2752

M18-39

2752

25.2M→Finish

25.2 - 26.2 mi

Top 14%
×2stories
+22ft-21ft

Overall

4098

Males

3501

M18-39

3501

Passing Analysis

Category:
Athletes Passed
1904
Passed By
433
Net Change
+1471
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#5153
5K → 10K28992+197#5153#4956
10K → 15K33913+326#4956#4630
15K → 20K25712+245#4630#4385
20K → Half2815+13#4385#4372
Half → 25K21512+203#4372#4169
25K → 30K23638+198#4169#3971
30K → 20M9521+74#3971#3897
20M → 21M10121+80#3897#3817
21M → 35K2835-7#3817#3824
35K → 23M8257+25#3824#3799
23M → 24M6921+48#3799#3751
24M → 40K4744+3#3751#3748
40K → 25.2M418+33#3748#3715
25.2M → Finish7744+33#3715#3682
TOTALS1904433+1471
📊

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