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BOSTON MARATHON 2025

Nathan Lo

Bib: 6429•M

CA

0:00
0:00
/ mi
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Overall
#0 / 28404
Top 20%
Gender (Male)
#0 / 16105
Top 32%
Division (M18-39)
#0 / 5642
Race Day Weather
50°/40°F
broken clouds

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
19:14
Rank: #1811
Start → 5K
19:14 | 6:11/mi
10K· 6.21 mi
39:27
Rank: #2723 (-912)
5K → 10K
20:13 | 6:30/mi
15K· 9.32 mi
59:18
Rank: #2750 (-27)
10K → 15K
19:51 | 6:23/mi
20K· 12.43 mi
1:19:41
Rank: #2939 (-189)
15K → 20K
20:23 | 6:34/mi
Half· 13.11 mi
1:24:04
Rank: #2948 (-9)
20K → Half
4:23 | 6:25/mi
25K· 15.53 mi
1:40:13
Rank: #3054 (-106)
Half → 25K
16:09 | 6:40/mi
30K· 18.64 mi
2:02:19
Rank: #3399 (-345)
25K → 30K
22:06 | 7:07/mi
20M
2:15:22
Rank: #4679 (-1280)
30K → 20M
13:03 | 9:36/mi
21M
2:23:20
Rank: #4816 (-137)
20M → 21M
7:58 | 7:58/mi
35K· 21.75 mi
2:28:54
Rank: #4942 (-126)
21M → 35K
5:34 | 7:26/mi
23M
2:38:51
Rank: #5240 (-298)
35K → 23M
9:57 | 7:57/mi
24M
2:46:47
Rank: #5403 (-163)
23M → 24M
7:56 | 7:56/mi
40K· 24.85 mi
2:54:24
Rank: #5664 (-261)
24M → 40K
7:37 | 8:54/mi
25.2M
2:57:20
Rank: #5674 (-10)
40K → 25.2M
2:56 | 8:30/mi
Finish· 26.22 mi
3:04:54
Rank: #5734 (-60)
25.2M → Finish
7:34 | 7:26/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:24:04
Pace6:25 /mi
2nd Half
Distance13.11 mi
Time1:40:50
Pace7:42 /mi
📊Positive Split: 19.9% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:24:0419:146:1119:14
6:11
-
10K
6.21 mi10:44:1739:276:2120:13
6:30
+0:19
15K
9.32 mi11:04:0859:186:2219:51
6:23
-0:07
20K
12.43 mi11:24:311:19:416:2520:23
6:34
+0:11
Half
13.11 mi11:28:541:24:046:254:23
6:25
-0:09
25K
15.53 mi11:45:031:40:136:2716:09
6:40
+0:15
30K
18.64 mi12:07:092:02:196:3422:06
7:07
+0:27
20M
20.00 mi12:20:122:15:226:4613:03
9:36
+2:29
21M
21.00 mi12:28:102:23:206:507:58
7:58
-1:38
35K
21.75 mi12:33:442:28:546:515:34
7:26
-0:32
23M
23.00 mi12:43:412:38:516:549:57
7:57
+0:31
24M
24.00 mi12:51:372:46:476:577:56
7:56
-0:01
40K
24.85 mi12:59:142:54:247:017:37
8:54
+0:58
25.2M
25.20 mi13:02:102:57:207:022:56
8:30
-0:24
Finish
26.22 mi13:09:443:04:547:037:34
7:26
-1:04

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

6:11 /mi

Average Pace

7:03 /mi

Slowest Pace

9:36 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

1:40:13

54% of race

Time at Steady Pace

35:14

19% of race

Time at Slower Pace

49:27

27% of race

Average Pace: 7:03 /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 mi10:24:0419:146:1119:14
6:11
#1811
10K
6.21 mi10:44:1739:276:2120:13
6:30
#2723
15K
9.32 mi11:04:0859:186:2219:51
6:23
#2750
20K
12.43 mi11:24:311:19:416:2520:23
6:34
#2939
Half
13.11 mi11:28:541:24:046:254:23
6:25
#2948
25K
15.53 mi11:45:031:40:136:2716:09
6:40
#3054
30K
18.64 mi12:07:092:02:196:3422:06
7:07
#3399
20M
20.00 mi12:20:122:15:226:4613:03
9:36
#4679
21M
21.00 mi12:28:102:23:206:507:58
7:58
#4816
35K
21.75 mi12:33:442:28:546:515:34
7:26
#4942
23M
23.00 mi12:43:412:38:516:549:57
7:57
#5240
24M
24.00 mi12:51:372:46:476:577:56
7:56
#5403
40K
24.85 mi12:59:142:54:247:017:37
8:54
#5664
25.2M
25.20 mi13:02:102:57:207:022:56
8:30
#5674
Finish
26.22 mi13:09:443:04:547:037:34
7:26
#5734
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM18-39Seg. OverallSeg. MalesSeg. M18-39
5K3.11 mi3.11 mi1811172117212869(Top 10%)2734(Top 17%)2734(Top 48%)
10K6.21 mi3.10 mi2723-9122594-8732594-8733778(Top 13%)3563(Top 22%)3563(Top 63%)
15K9.32 mi3.11 mi2750-272622-282622-282869(Top 10%)2734(Top 17%)2734(Top 48%)
20K12.43 mi3.11 mi2939-1892800-1782800-1783477(Top 12%)3292(Top 20%)3292(Top 58%)
Half13.11 mi0.68 mi2948-92809-92809-93226(Top 11%)3067(Top 19%)3067(Top 54%)
25K15.53 mi2.42 mi3054-1062911-1022911-1023864(Top 14%)3619(Top 22%)3619(Top 64%)
30K18.64 mi3.11 mi3399-3453216-3053216-3055382(Top 19%)4840(Top 30%)4840(Top 86%)
20M20.00 mi1.36 mi4679-12804337-11214337-112119600(Top 69%)11962(Top 74%)11962(Top 212%)
21M21.00 mi1.00 mi4816-1374449-1124449-1127129(Top 25%)5744(Top 36%)5744(Top 102%)
35K21.75 mi0.75 mi4942-1264542-934542-938141(Top 29%)6364(Top 40%)6364(Top 113%)
23M23.00 mi1.25 mi5240-2984779-2374779-2379591(Top 34%)7013(Top 44%)7013(Top 124%)
24M24.00 mi1.00 mi5403-1634909-1304909-13010731(Top 38%)7535(Top 47%)7535(Top 134%)
40K24.85 mi0.85 mi5664-2615090-1815090-18115751(Top 55%)9779(Top 61%)9779(Top 173%)
25.2M25.20 mi0.35 mi5674-105091-15091-18718(Top 31%)6277(Top 39%)6277(Top 111%)
Finish26.22 mi1.02 mi5734-605120-295120-298629(Top 30%)6235(Top 39%)6235(Top 111%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 10%
×21stories
+97ft-345ft

Overall

2869

Males

2734

M18-39

2734

5K→10K

3.1 - 6.2 mi

Top 13%
×5stories
+79ft-138ft

Overall

3778

Males

3563

M18-39

3563

10K→15K

6.2 - 9.3 mi

Top 10%
×3stories
+67ft-78ft

Overall

2869

Males

2734

M18-39

2734

15K→20K

9.3 - 12.4 mi

Top 12%
×5stories
+106ft-86ft

Overall

3477

Males

3292

M18-39

3292

20K→Half

12.4 - 13.1 mi

Top 11%
×2stories
+19ft-37ft

Overall

3226

Males

3067

M18-39

3067

Half→25K

13.1 - 15.5 mi

Top 14%
×4stories
+66ft-88ft

Overall

3864

Males

3619

M18-39

3619

25K→30K

15.5 - 18.6 mi

Top 19%
×9stories
+181ft-148ft

Overall

5382

Males

4840

M18-39

4840

30K→20M

18.6 - 20.0 mi

Top 69%
×5stories
+64ft-50ft

Overall

19600

Males

11962

M18-39

11962

20M→21M

20.0 - 21.0 mi

Top 25%
×8stories
+106ft-24ft

Overall

7129

Males

5744

M18-39

5744

21M→35K

21.0 - 21.8 mi

Top 29%
×7stories
+17ft-86ft

Overall

8141

Males

6364

M18-39

6364

35K→23M

21.8 - 23.0 mi

Top 34%
×5stories
+23ft-63ft

Overall

9591

Males

7013

M18-39

7013

23M→24M

23.0 - 24.0 mi

Top 38%
×6stories
+12ft-82ft

Overall

10731

Males

7535

M18-39

7535

24M→40K

24.0 - 24.9 mi

Top 55%
×1story
+6ft-20ft

Overall

15751

Males

9779

M18-39

9779

40K→25.2M

24.9 - 25.2 mi

Top 31%
×1story
+13ft-16ft

Overall

8718

Males

6277

M18-39

6277

25.2M→Finish

25.2 - 26.2 mi

Top 30%
×2stories
+22ft-21ft

Overall

8629

Males

6235

M18-39

6235

Passing Analysis

Category:
Athletes Passed
379
Passed By
4302
Net Change
-3923
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#1811
5K → 10K1913-912#1811#2723
10K → 15K6289-27#2723#2750
15K → 20K35224-189#2750#2939
20K → Half1221-9#2939#2948
Half → 25K39145-106#2948#3054
25K → 30K44389-345#3054#3399
30K → 20M11281-1280#3399#4679
20M → 21M32169-137#4679#4816
21M → 35K32158-126#4816#4942
35K → 23M30328-298#4942#5240
23M → 24M16179-163#5240#5403
24M → 40K9270-261#5403#5664
40K → 25.2M2737-10#5664#5674
25.2M → Finish3999-60#5674#5734
TOTALS3794302-3923
📊

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