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BOSTON MARATHON 2025

Jefferson Lo

Bib: 31138•M

0:00
0:00
/ mi
Masters
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Overall
#0 / 28404
Gender (Male)
#0 / 16105
Masters (Masters Men)
#0 / 10463
Division (M45-49)
#0 / 2386
Race Day Weather
50°/40°F
broken clouds

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
29:03
Rank: #23730
Start → 5K
9:21/mi
29:03 split
10K· 6.21 mi
58:04
Rank: #23711 (+19)
5K → 10K
9:20/mi
29:01 split
15K· 9.32 mi
1:26:50
Rank: #23495 (+216)
10K → 15K
9:16/mi
28:46 split
20K· 12.43 mi
1:56:08
Rank: #23268 (+227)
15K → 20K
9:26/mi
29:18 split
Half· 13.11 mi
2:02:24
Rank: #23240 (+28)
20K → Half
9:11/mi
6:16 split
25K· 15.53 mi
2:25:45
Rank: #23055 (+185)
Half → 25K
9:38/mi
23:21 split
30K· 18.64 mi
2:57:08
Rank: #22808 (+247)
25K → 30K
10:06/mi
31:23 split
20M
3:11:08
Rank: #22737 (+71)
30K → 20M
10:18/mi
14:00 split
21M
3:22:07
Rank: #22643 (+94)
20M → 21M
10:59/mi
10:59 split
35K· 21.75 mi
3:29:44
Rank: #22607 (+36)
21M → 35K
10:11/mi
7:37 split
23M
3:43:06
Rank: #22595 (+12)
35K → 23M
10:41/mi
13:22 split
24M
3:53:33
Rank: #22576 (+19)
23M → 24M
10:27/mi
10:27 split
40K· 24.85 mi
4:03:00
Rank: #22609 (-33)
24M → 40K
11:03/mi
9:27 split
25.2M
4:07:10
Rank: #22619 (-10)
40K → 25.2M
12:05/mi
4:10 split
Finish· 26.22 mi
4:17:45
Rank: #22684 (-65)
25.2M → Finish
10:23/mi
10:35 split

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time2:02:24
Pace9:20 /mi
2nd Half
Distance13.11 mi
Time2:15:21
Pace10:19 /mi
📊Positive Split: 10.6% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi11:52:5429:039:2129:03
9:21
-
10K
6.21 mi12:21:5558:049:2129:01
9:20
-0:01
15K
9.32 mi12:50:411:26:509:1928:46
9:16
-0:04
20K
12.43 mi13:19:591:56:089:2129:18
9:26
+0:10
Half
13.11 mi13:26:152:02:249:206:16
9:11
-0:15
25K
15.53 mi13:49:362:25:459:2323:21
9:38
+0:27
30K
18.64 mi14:20:592:57:089:3031:23
10:06
+0:28
20M
20.00 mi14:34:593:11:089:3314:00
10:18
+0:12
21M
21.00 mi14:45:583:22:079:3710:59
10:59
+0:41
35K
21.75 mi14:53:353:29:449:397:37
10:11
-0:48
23M
23.00 mi15:06:573:43:069:4213:22
10:41
+0:30
24M
24.00 mi15:17:243:53:339:4410:27
10:27
-0:14
40K
24.85 mi15:26:514:03:009:479:27
11:03
+0:36
25.2M
25.20 mi15:31:014:07:109:484:10
12:05
+1:02
Finish
26.22 mi15:41:364:17:459:5010:35
10:23
-1:42

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

9:11 /mi

Average Pace

9:50 /mi

Slowest Pace

12:05 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

2:25:45

57% of race

Time at Steady Pace

1:14:02

29% of race

Time at Slower Pace

37:58

15% of race

Average Pace: 9:50 /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 mi11:52:5429:039:2129:03
9:21
#23730
10K
6.21 mi12:21:5558:049:2129:01
9:20
#23711
15K
9.32 mi12:50:411:26:509:1928:46
9:16
#23495
20K
12.43 mi13:19:591:56:089:2129:18
9:26
#23268
Half
13.11 mi13:26:152:02:249:206:16
9:11
#23240
25K
15.53 mi13:49:362:25:459:2323:21
9:38
#23055
30K
18.64 mi14:20:592:57:089:3031:23
10:06
#22808
20M
20.00 mi14:34:593:11:089:3314:00
10:18
#22737
21M
21.00 mi14:45:583:22:079:3710:59
10:59
#22643
35K
21.75 mi14:53:353:29:449:397:37
10:11
#22607
23M
23.00 mi15:06:573:43:069:4213:22
10:41
#22595
24M
24.00 mi15:17:243:53:339:4410:27
10:27
#22576
40K
24.85 mi15:26:514:03:009:479:27
11:03
#22609
25.2M
25.20 mi15:31:014:07:109:484:10
12:05
#22619
Finish
26.22 mi15:41:364:17:459:5010:35
10:23
#22684
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM45-49Seg. OverallSeg. MalesSeg. M45-49
5K3.11 mi3.11 mi23730141201412023068(Top 81%)13873(Top 86%)13873(Top 581%)
10K6.21 mi3.10 mi23711+1914114+614114+623644(Top 83%)14096(Top 88%)14096(Top 591%)
15K9.32 mi3.11 mi23495+21614022+9214022+9223068(Top 81%)13873(Top 86%)13873(Top 581%)
20K12.43 mi3.11 mi23268+22713938+8413938+8422671(Top 80%)13648(Top 85%)13648(Top 572%)
Half13.11 mi0.68 mi23240+2813924+1413924+1422519(Top 79%)13565(Top 84%)13565(Top 569%)
25K15.53 mi2.42 mi23055+18513825+9913825+9922288(Top 78%)13422(Top 83%)13422(Top 563%)
30K18.64 mi3.11 mi22808+24713675+15013675+15021907(Top 77%)13120(Top 81%)13120(Top 550%)
20M20.00 mi1.36 mi22737+7113610+6513610+6521872(Top 77%)12996(Top 81%)12996(Top 545%)
21M21.00 mi1.00 mi22643+9413555+5513555+5521343(Top 75%)12672(Top 79%)12672(Top 531%)
35K21.75 mi0.75 mi22607+3613523+3213523+3222375(Top 79%)13097(Top 81%)13097(Top 549%)
23M23.00 mi1.25 mi22595+1213495+2813495+2822467(Top 79%)13090(Top 81%)13090(Top 549%)
24M24.00 mi1.00 mi22576+1913454+4113454+4122676(Top 80%)13146(Top 82%)13146(Top 551%)
40K24.85 mi0.85 mi22609-3313456-213456-223261(Top 82%)13371(Top 83%)13371(Top 560%)
25.2M25.20 mi0.35 mi22619-1013450+613450+623381(Top 82%)13461(Top 84%)13461(Top 564%)
Finish26.22 mi1.02 mi22684-6513464-1413464-1423994(Top 84%)13762(Top 85%)13762(Top 577%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 81%
×21story building
+97ft-345ft

Overall

23068

Males

13873

M45-49

13873

5K→10K

3.1 - 6.2 mi

Top 83%
×5story building
+79ft-138ft

Overall

23644

Males

14096

M45-49

14096

10K→15K

6.2 - 9.3 mi

Top 81%
×3story building
+67ft-78ft

Overall

23068

Males

13873

M45-49

13873

15K→20K

9.3 - 12.4 mi

Top 80%
×5story building
+106ft-86ft

Overall

22671

Males

13648

M45-49

13648

20K→Half

12.4 - 13.1 mi

Top 79%
×2story building
+19ft-37ft

Overall

22519

Males

13565

M45-49

13565

Half→25K

13.1 - 15.5 mi

Top 78%
×4story building
+66ft-88ft

Overall

22288

Males

13422

M45-49

13422

25K→30K

15.5 - 18.6 mi

Top 77%
×9story building
+181ft-148ft

Overall

21907

Males

13120

M45-49

13120

30K→20M

18.6 - 20.0 mi

Top 77%
×5story building
+64ft-50ft

Overall

21872

Males

12996

M45-49

12996

20M→21M

20.0 - 21.0 mi

Top 75%
×8story building
+106ft-24ft

Overall

21343

Males

12672

M45-49

12672

21M→35K

21.0 - 21.8 mi

Top 79%
×7story building
+17ft-86ft

Overall

22375

Males

13097

M45-49

13097

35K→23M

21.8 - 23.0 mi

Top 79%
×5story building
+23ft-63ft

Overall

22467

Males

13090

M45-49

13090

23M→24M

23.0 - 24.0 mi

Top 80%
×6story building
+12ft-82ft

Overall

22676

Males

13146

M45-49

13146

24M→40K

24.0 - 24.9 mi

Top 82%
×1story
+6ft-20ft

Overall

23261

Males

13371

M45-49

13371

40K→25.2M

24.9 - 25.2 mi

Top 82%
×1story
+13ft-16ft

Overall

23381

Males

13461

M45-49

13461

25.2M→Finish

25.2 - 26.2 mi

Top 84%
×2story building
+22ft-21ft

Overall

23994

Males

13762

M45-49

13762

Passing Analysis

Category:
Athletes Passed
1877
Passed By
831
Net Change
+1046
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#23730
5K → 10K247228+19#23730#23711
10K → 15K28266+216#23711#23495
15K → 20K27043+227#23495#23268
20K → Half4719+28#23268#23240
Half → 25K23146+185#23240#23055
25K → 30K30154+247#23055#22808
30K → 20M11544+71#22808#22737
20M → 21M11925+94#22737#22643
21M → 35K6125+36#22643#22607
35K → 23M7462+12#22607#22595
23M → 24M6445+19#22595#22576
24M → 40K2962-33#22576#22609
40K → 25.2M1626-10#22609#22619
25.2M → Finish2186-65#22619#22684
TOTALS1877831+1046
📊

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